FSAE-A 2012 Car Swap

[Shooter]

I just thought I'd start a thread similar to last years giving drivers the opportunity to provide constructive feedback to teams who's cars they drove on Monday. It would be good to provide comparisons between cars that you drove on Monday as well as cars you have driven previously.

Thank you to Edith Cowan and RMIT combustion for giving me the opportunity to drive both of their cars on Monday. I will draft up some thoughts on both of these cars, they were both fantastic in different ways.

[Shooter]

Firstly a little about me, I started driving competitively for Monash last year in Endurance and have since driven Autocross and Endurance at FSUK, FSG and FSAE-A 2012.

Cars I drove on Monday were Edith Cowan’s and RMIT combustion. Both of these cars surprised me with their pace and very high levels of grip, despite RMIT’s lack of aero.

Ergonomics:
RMIT: I am a little over 6 feet tall so RMIT’s car was a bit of a squeeze for me, how this car fits the 95th percentile male I’m not quite sure but I am almost certain that they would be extremely uncomfortable, leg room is the primary issue as I had to wedge my knees into the recess under the front roll hoop, this also put my legs very close to the steering wheel. In Europe they have started including the 95th percentile male in scrutineering and design and if the same rule came to Australia you could be struggling. Elbow room was also a slight issue though not as much as your team made out. The biggest issue with ergo was the complete lack of lateral support given by the seat (or lack of one) resulting in sliding from one side of the cockpit to the other through slaloms. I have the upmost respect for those that drove such a fast endurance as I’m sure it would not have been easy, I’m sure the driver’s lateral movement was the main contributor to their elbows hitting the side walls of the monocoque. Even some foam either side of the driver would be a great improvement giving the driver better feedback from the car.

ECU: The ECU car had a very low and reclined driving position though visibility was hardly a limiting factor in avoiding cones as I thought it would have been with such a tall front wing. The seat had great lateral support which I’m sure would improve even further with a custom insert. The steering wheel position was almost perfect and I had ample elbow room. With such a reclined driving position the pedals were a bit close for me, putting my legs a little close to the steering wheel and making it slightly uncomfortable to keep my feet off the pedals. I would recommend looking into an adjustable pedal box. Once the engine started hunting I am guessing my foot kept touching the throttle, making it worse. I remember your taller skidpad driver having the same issue and I am guessing that it could be part of the problem. It may not need to be driver adjustable like the monash car but it would be good to have for changing between events to suit different drivers.

Monash: The seat is the real standout of the Monash car, giving excellent feedback and allowing no lateral movement. This car has by far the best ergonomics of the three which I think can largely be attributed to the adjustable pedal box. Elbow room is great due to the low sides though I have hit my elbow on the side impact tubes once or twice, not a big issue but it will need to be addressed for next year’s car. After driving ECU’s car I actually think there is too much visibility, bigger wing needed?

Steering:
All cars had very direct steering with impressively low freeplay, RMIT and monash had very fast steering rates allowing for very fast corrections. ECU’s was much slower though this allowed more finesse during slaloms. The only downside to this could be the speed at which the driver can steer being the limiting factor during high speed lane changes similar to those seen at the competition this year. RMIT actually felt like it had the highest steering effort of the three which was surprising given the lack of aero, ECU’s was by far the lightest and would be great over an endurance length. As far as feel goes, all three cars were outstanding though RMIT was probably the best. Understeer could be felt easily though this could be the result of the Hoosier LC0’s shuddering which is hardly ever seen on the Goodyear 2704’s.

Brakes:
Monash by a mile as far as feel, ECU’s car stopped extremely quickly though I didn’t get much feel from the pedal, RMIT’s car just couldn’t keep up in this area, maybe the aero made the difference. I would say that the RMIT car could use more rear bias as the fronts kept locking.

Tyres:
The LC0’s on the RMIT car are much more forgiving than the 2704’s on Monash and ECU which like smaller slip angles. Both tyres had huge levels of grip even on lap one with the RMIT car being faster through the hairpin, either this was tyres or just weight. The ECU car was easy to drive smoothly, encouraging you to not be too aggressive with the steering, probably because of the lower steering rate.

Engine:
ECU had this one by a mile with a very torquey four which allowed you to reach insane speeds even on the short bursts between corners. This track certainly favoured the four cylinder cars with such long straights. RMIT and Monash had similar speed out of slow corners though the drag soon slows the monash car down, this is mostly overcome by the higher entry speed onto most straights followed by much later braking. The RMIT electric shifter worked only intermittently, the Monash mechanical shifter was the most reassuring but could not match the ECU pneumatic setup on the straights. I would still recommend that the ECU guys look into actuating the clutch pneumatically on the downshifts as it gives the driver a lot less to think about. In saying that it took only 2 shifts to get used to the right hand clutch, left hand shift arrangement and it caused me no issues after that.

Aero:
I would say the monash car still has a fair bit more downforce than ECU though may be into the region of diminishing returns as the ECU car was extremely quick through high speed lane changes. The Monash car’s unsprung aero is certainly better than ECU’s sprung wings dynamically as a scraping wing in high speed cornering was very distracting, maybe stiffer springs or anti roll bars would fix the problem. RMIT’s car would be faster with even a smaller wing IMO, this would also stop cones from getting stuck in the front suspension which is a problem that I have seen during endurance.

General comments and dynamics:
The ECU car appeared to be underdamped and needed anti roll bars to stop the car from diving onto the front outside tyre causing the wing to scrape. With a little development, this car would have been unstoppable at the competition, I would say it had more potential to go faster than the Monash or RMIT car, I have no idea what my lap times were in it though it felt pretty quick even though I was holding back quite a lot.

The monash car is the most composed though is very unforgiving, a small error could loose you a second due to the inability to make up the time on the straights. Smoothness is the key to this car.

The RMIT car has a bit too much understeer which I suspect is the result of the guys trying very hard to keep the inside rear wheel on the ground as I noticed that the inside rear wheel loved to spin up on corner exit. The car may have been quicker with a spool or maybe more preload in the diff? The lower yaw inertia and overall weight made this car great in transient and through the hairpin though it did not inspire driver confidence the same way the others did. I would say that it certainly encourages us to keep the weight of the wing down as well as the outboard suspension components to improve our low speed performance.

That is all I can think of right now, if you have any questions feel free to email me.

chris . heath (at) monashmotorsport . com no spaces

[mdavis]

Any chance of pictures of the Monash seat, for those of us not able to actually see the Australian cars? Thanks!

[Micko..]

Chris,
Great write up, I wish this car swap business was around back when I was playing. But then agian it would seriously slow down the afterparty.

I would love to see an unofficial timed event the next day where a contoll driver has 3 laps in each car and could give feeback like you have to teams. I think it also gives a better idea of what the competition is all about... building a car for someone who wants to jump in and drive... not for teams to have a heap of seat time with divers of various skill levels.

Two control drivers at either end of the 95th percentile. Each drive every car... quickest combined times (of the fastest lap) wins.

[Boffin]

I’ll weigh in here too. RMIT was the only car I drove during the day.
The history of me driving is competitively I drove accell in the 2010 comp, and skidpad, accel and autocross in Japan.
However the full list of cars I’ve driven are:
Swinburne Petrol 09
Swinburne Petrol 10
Swinburne Petrol 10J (Japanese spec)
Melbourne 10
Melbourne 11
Monash 10
Monash 11
UTS 11

Ergo:
I’m 5’10”, 100kg and I had no problem fitting in the car comfortably. The cars small size actually works for it in this manner. No heel plate on the pedal box or foot locators were a small issue when compared to cars that have had them.
There was not much length in the footwell, meaning that my knees were high and against the side of the tub. This was actually a strength because it meant I had a natural tendency to have my feet pushing against/towards the pedals and with my knees hard against the sides gave them no chance to bang around on track against the sides. I never noticed while out on track that my feet slipped of the pedals.
The lack of support was noticeable when strapping into the car, but I did not notice when out on track. This may have to do with how I was strapped into the car (I lifted my bum off the floor of the car, and had the belts tightened as much as possible), and had my elbows down between my sides and the monocoque.

The biggest concern ergo wise was the lack of elbow room. Because of this I could not achieve enough lock onto the steering wheel to make the hairpin more often than not. Steering wheel weight was fine, but once I deviated about 45? from straight the restriction on elbow space meant my wrists were at their limit their angle, hence no more lock. I could get more lock by raising my elbows above and out of the tub, but that is an easy way to get blacked flagged. This limit on lock was a real concern at the hairpin, uncomfortable elsewhere but not restricting my speed.
Another 6” of space either side in the tub, or running a low side like Monash or Swinburne 12 electric would be a significant improvement.

Steering weight wise, the car is about the middle of the road of what I have experienced. Heavier than Swinburne’s cars (lightes weight so far), but lighter than Monash’s cars. Personally it was a little bit heavy for my preference, but it did not wear you out of make you work too hard.

The car
I was given enough warning that the “paddle” shifter required to be pressed and held until a gear was engaged. Having come from a mechanical shifter that has been ran with & without a cut spark I had no problem accommodating to it. Swinburne has never used a clutch to shift (which does change the shift style slightly – more so when no cut spark), hence no problem to adjust. The car gave enough feedback to tell me when the gear was engaged.
It was probably the best shifter (outside of occasionally not grabbing gear – which could be adjusted out with driving style/time)I have used as that was where your thumbs normally sat and allowed you to keep firmly griped on to the steering wheel. A cut spark to the engine would be the only improvement to make, and would make the upshifts more predictable.
Due to being a single with a lot of low down torque, you were able to stay in second gear and not lose too much time. A minimal amount of time would be gained by using first in the hairpin. However second gear did encourage more inner wheel spin exiting corners. Reflecting on this, it would have made the car safer to drive, as it required you to straighten the car up before being able to get onto the gas. Good for novice drivers, bad for the more experienced. I won’t touch on the diff anymore since it was a known problem.

Engine wise, the single is very similar to that of Monash, in that it is enough power. Having had 68kw and 75nm from Swinburne’s car, I was not left wanting more power.
It has enough for what it needs to accomplish.
No notable lag when getting on the throttle, and enough torque response when you do. The rpm limiter was easy to hit, probably more due to me expecting and used to having more revs available.

The car didn’t naturally feel as fast, when compared to Monash 11. There is a huge amount of grip and response from the car, but it feels like it has to be driven to achieve it. Whereas with the Monash 11 car, the grip (and thus speed) is there from the start and comes easily (finding and reaching the limit is hard).
For Monash 11, I would say 80% of the speed is normally there and the driver has to find the remaining 20%, but with RMIT 12, 50% of the speed is there and the driver has to find the remaining 50%. Ultimate speed would be fairly similar, with maybe a slight advantage to Monash 11.

Ultimate grip is deceiving with how hard you can push round corners and how late you can leave it to brake. Coming up over the hill towards to slalom you could leave your brakeing marker till pretty much when the nose of the car is into at the first row of cones marking the start of the slalom.
If you overshoot/overcook a turn the tyres are extremely forgiving in being able to recover. In the above situation I sometimes locked the one of the front wheels, hence sailing past the turn in apex trying to recover, but once I had wiped of enough speed and released the brake pedal the car was still able to make it through without hitting any cones.

It had a tendency to understeer, but thinking back this was more so when you attempted to trail brake the car. That is more of a trait of the tyres, and I would guess the tyre traction ellipse would show this. Individually either motion (brake or steering) has great grip that is available immediately from cold tyres.

A problem that I had (outside of my now sore elbows) is to judge spatially where the rear end of the car was, which effected how close I could get to cones (not knowing if I had hit one). I not sure whether this is a trait of the car, or is I am simply to use to bigger cars on 13” or because I haven’t driven a FSAE car in 12 months.

All up a big thankyou to the RMIT guys for letting me in there car, as it pretty much complete my deck on “car concepts” that I have driven (lightweight single). The only ones missing now are, lightweight 10” single with wings (I wonder who that will be in the future….) and an electric powertrain car.

[Shooter]

Micko, I agree that would be a good way to see who's car is actually best but we aim for driver swap to be an opportunity to learn from other teams and to see where your own car is lacking. Personally I learnt alot from driving a few cars this year as well as last year.

This is the monash 2010 seat which is the same mould as currently used:

http://sphotos-b.ak.fbcdn.net/hphotos-ak-ash4/397065_10151284264719512_1153023713_n.jpg

[Scott Wordley]

Thanks for kicking off this thread with some great posts Shooter (Chris) and Boffin.

Excuse the typos, doing this on my phone.

I had the great pleasure of driving the Curtin Motorsport car #14.

Before I get into my feedback I would like to note that the Curtin guys managed 10 stints of 5 laps on the comp track Monday, which was more than any other team. I think the majority of these were people on other teams, which is tremendously generous, not to mention impressive on a technical level. Building cars like this, which can drive hard all day in the heat and not
boil, destroy oil or tyres or break is a sure sign of a team on the way up.

My driving experience:

I have driven:
Monash 2000, 2001, 2002, 2003, 2005, 2006, 2007, 2008, 2000, 2010. I haven't driven our singles from 11 or
12... Yet.

I was a comp accel and autox driver for 2004UK and skidpan for 2007AUS from memory.
Despite this I am not a great driver of tear cars, and pretty unfit for the demands of these cars today. 6 hours sleep in the previous 3 days didnt help either! I am also 6'1" and 100kg so ergo is frequently a problem.

To the Curtin car.

Getting in the car I found the seat to be really good, accommodated me fine. The pedals were a little closer than I would have liked but there may have been more adjustment that we didn't utilize.

Because of this my knees were high and close to the wheel. The team had a big and a small wheel so we use to small for a bit more clearance.

One really neat feature of this car was the telescoping steering column, allowing me to bring the wheel closer and get more room to turn it without hitting my legs. Really neat and would love to see some pics posted here. Will be recommending it to the monash guys.

Brake and accel pedals were good, nice an solid with no
noticeable flex.

Gear shift was pretty standard on the left with a butterfly cable clutch. Shifter linkage felt solid with little friction and you could feel the gearbox nicely. Personally I would have prefered it further forward closer to the wheel, to reduce the time to get your hand to it and then back on the wheel. I found myself looking for it on shifts as it was just outside my peripheral vision.

Visibility from the cockpit was fine, searing position nice and reclined. Seat was solid and transmitted good feedback.

The guys told me there were rpm lights on the dash but I don't recall seeing them once, perhaps they were obscured by the wheel.

Setting off I took a couple of slow laps to feel out the car. I hadn't driven one in a while, nor the werribee track before.

The engine in this car was really great. Getting into the powerband turned the scenery into a blur. It was hard to stop smiling. Interested to know exactly how much it is putting out. It did come on pretty suddenly though so would take a skilled and confident driver to keep it in the zone. Would also require a lot of hard revving in first which might hurt fuel. I think a shorter ratio (higher number) would allow you to drive more of the course in second but in the powerband rather than below it, at the expense of needing 3rd for all the straights. You could go the other way and use 1-2 but the stock ratio gap is probably to big.

Shifting was clean and reliable.

It was the first time I had drive a Hoosier shod car.
Had a feel somewhere between the avons and the goodies, quite forgiving but lacking a little sharpness.

The brakes felt a little too forward biased and I found it easy to pinch inside fronts on corner entry. This made trail breaking difficult. It also prevented you from jabbing the brakes to get the weight forward and
Male the front end point which is a handy technique for slaloms and tight stuff. I ended up doing most of my turning off the brakes.

The steering ratio felt nice and quick, but i found the Effort to be way to high. It felt like way to much scrub, I think I guessed about 30-40mm. The team later suggested to me that it was even more than that, so there is your problem. Suggest more wheel offset next year guys. I couldn't feel much castor in the car, and would probably like a little more once the scrub is
reduced. I really struggled to feel the grip limit of the car. The scrub would have masked a lot of it, but suggest you experiment with reducing the mechanical trail (castor offset?) so that you can feel the pneumatic trail and grip limit more clearly. Cars with this ratio right feel nice and light in the steering on the limit. I didn't look what you had currently sorry. I didnt look at what Ackerman you were running either but I felt it could use some more, the front wheels felt bit too parallel and you could hear them fighting a little. I like cars to drag that inside wheel, and to feel like the yaw centre / turn centre is further back. More toe front and rear might have helped as well.

Springing, shocks and bars were ok, but I would prefer stiffer all round. Car took a little to long to take a set, although I concede this helped get the power down.

I struggled with the ergo due to my size and low fitness. I had no room to swing
My elbows Given the high and tight chassis sides so i resorted to locking my elbows
Against the side of the chassis and driving with my wrists and hands, which is always a recipe for rapid fatigue. Incouldnt get enough steering angle with mu hands on the wheel in the correct place, so After a couple
of laps I found myself Taking a bite of the wheel before each corner, turning, releasing it and letting it self centre then taking a bit the other way. This slows down your steering inputs massively, and leave the car uncontrolled in transition. Luckily I grabbed enough lock most times, but I was left with no outs if I had entered the hairpin wrong. I dont think a could have driven a 6th lap, arms and pecs were dead. Some
More cockpit space, low sides or angling up the steering wheel could fix this issue for large drivers like myself.

All in all a very impressive car, great level of finish and very capable dynamically in the right hands. A few ergo tweaks would make it must more accommodating for a bigger range of drivers.

Thanks again for the opportunity guys, I am looking forward to hearing from pete marsh of Uwa and Trav from monash who I know also drove the car.

[mdavis]

@ shooter, thank you.

-Matt

[Andrew Gunn]

Hi everyone, I'll also write up my feedback for the cars I drove on Monday.

Just quickly though I'd like to thank everyone at the event for such an interesting and friendly meeting. I learnt a lot and I'm looking forward to next year already!

On the day I drove the Curtin, Sophia and RMIT comb cars. Other than those cars this is my first year in FSAE, and I've driven the '11 and '12 (autoX and enduro) Melbourne cars, as well as past experience in karts. I'm 6'0" and 75kg.

Curtin:

Ergo - I drove with the seat insert that the taller and narrower driver used, it was quite a well made insert (maybe could do with something to actually connect it to the seat) that offered a lot more lower back and rib support that the seat lacked for someone my size. The variable steering column length was fantastic; I preferred the shortest length, as it allowed me to use my upper arms more to turn. By far the best thing about the ergo on the car was the shifter. It had a perfect weight with very little play, and it's highlight feature was the clutch (mounted on the rear side of the gearstick) which was at a tension which allowed just a quick push (no gripping of the gearstick) forward to change gear. Unfortunately I can't actually remember what the pedal box was like, really sorry.

Handling - It had a lot of push-on understeer. Also, I suppose due to it's weight (~240), it changed direction very slowly. Pre-apex the car I would have to carry on turning the steering wheel more and more as I got into the corner, which was scrubbing speed off and wearing down the fronts. It wasn't washing out on the front, and I couldn't break the rear grip, which leads me to think the balance was way too far to the rear, and I suggest try taking some grip off the rear, instead of adding to the front, because adding more grip overall won't help with changing direction faster, or coming off the corners nicely.

Engine - The power curve could definitely be improved. Pre 8000rpm there would be hardly any power, and then a huge surge of power up to around 12000rpm. This caused the car to sit very neutral off the corner (because of little power) and actually do what the driver wants out of the corner, but at the expense of time. I feel this is where the car could've gained the most time. The gears were well set.

Brakes - A little too much bias toward the front, and also the pedal was very tight and didn't have much feel. They stopped the car well, but I did lock the fronts way too often. Perhaps experience in the car would iron that out, but definitely changing the bias would allow for more stopping power.

Overall - I actually did the same time in this car on Monday as I did in our car on Saturday in the Autocross (49.8) and there are 3 things which I feel if they were changed would've made at least 8 tenths of a difference - they were just so apparent as slow through all corners. I can't really explain well why the car was fast then, it's probably something to do with the way it was very balanced off the corner, and must have a very solid top-end power.

Sophia:

Ergo - Far out I reckon this is the smallest cockpit ever made. Obviously it was the right size for the Sophia drivers, but I actually couldn't make it round the hairpins because my elbows were locked against my thighs and the side of the car (I then hit cones, stalled, and had to be rolled back to the pits - what an embarrassment). I feel like the build of the driver interface was quite good, although I really disliked the very very soft foot-operated clutch (which I struggled with) and throttle. The steering wheel had a little too much going on on it, but was a good size. If the whole thing was scaled up by about 1.3x I would have loved it! Also, the Sabelt harness was very intricate and time-consuming, it wasn't a 5 point, it was a 3 point, and looping around all the straps was slow.

Handling - Beautiful. So well balanced, so much feel for what's going on, so quick to change direction, so responsive. I feel the weight of the car has a lot to do with most of these things, but they really have excelled in creating a car which can be pushed hard and which a driver can be confident in, not scared of.

Engine - I felt it was quite weak in all areas compared to our car and the Curtin car, but that is almost certainly due to it being a mono cylinder. Relative to the RMIT car (which I suppose is closer) though, it was very different, had less grunt at the top end, but the bottom-end was very responsive and powerful.

Brakes - The best thing about this car. It just does exactly what you want it to do. So much range of pressure, and had a very easy to find sweet spot where the wheels would just chirp a little and you could still weave the car into the slaloms; very impressive. It had massive front brakes by the way.

Overall - I just wish I could've driven it for longer; I only did 2 laps in it. Also I wish I was a jockey or something so I could actually fit in it and drive properly, I feel it was the best FSAE car I've driven.

RMIT comb:

Ergo - Sorry guys, but the park-bench seat was really poor. You could never strap someone in hard enough for there upper body not to move around, and it was painful changing direction, I'm surprised your drivers made it through enduro! The buttons on the steering wheel for gear change was nice and ergonomic, but I found it was slow to change and wasted time. The pedals were also too far forward, as was the head rest. I was just too uncomfortable to go fast.

Handling - Compared to the Sophia, which had a similar weight, I couldn't believe how heavy the steering felt. It was like driving a kart, trying to use very little steering angle was something I'm not used to in an FSAE car. Putting too much work into the steering wheel just scrubbed a lot of speed off and was very tiring. The car felt like it was on rails most of the time, but if rear lost grip easily when lifting the throttle, and it was hard to correct that whilst trying to keep the steering wheel straight (see above). When the rear wasn't getting away from me though, it felt like it was on rails. Unfortunately the only way to get this feeling was to drive very smoothly, which from my experience is definitely not the best way to drive a FSAE car through some tight slaloms; it just didn't feel safe or easy to chuck this car into a corner, and I wasn't confident doing it. All in all the most different handling car to any of the other FSAE cars I've driven (and not in a good way unfortunately).

Engine - Had a lot of grunt out of the corner (shame the diff just sent it all to the wrong wheel and onto the limiter!), but I felt like it didn't pull well in the mid range. The gears were too close together, and due to the gear changing buttons, I found it so hard and slow to change up to 3rd. I would've liked to see a different gear changing mechanism (a gear stick maybe) and a spool, which would allow me to comment on the engine better, I feel these two features of the car kind of marred the engine, and didn't allow the potential power to be used.

Brakes - Too much front bias and quite weak overall. You just couldn't squeeze them to the limit, they just locked too quickly, which was scary because of the way the steering was so heavy (and it would just go super light when the fronts locked).

Overall - I didn't feel confident driving this car. It is definitely quick but I'd like to see a spool in it which would get rid of that annoying inside wheel spin out of the corner. The most time would come from the driver being comfortable though.


Due to my lack of knowledge and experience in car set up all I can really do is say what's wrong and right, and I struggle to give any kind of fix or cause. But I'm very happy I got to drive these cars because I learnt heaps and hopefully another opinion for the teams will help next year.

Cheers

[L B0MB]

Excellent feedback guys!

I remember discussing the scrub radius with Tim.Wright on the 2008 Curtin car.

It was exhausting to steer and after a short drive it felt like you had been smashing weights at the gym for an hour!

I think on that car the scrub was about 70mm and trail something like 40mm.

I've read advice on here about using a 20mm & 20mm combination. What are peoples thoughts on this?

Curtin feel free to divulge your numbers :-)

[acedeuce802]

The Car Swap seems like it was very valuable for all the teams involved. It's even great for us to read all of the feedback from the event. Even though we didn't get a chance to see or feel the cars discussed, it's good to hear the feedback about them. Thanks for sharing!

[Pete Marsh]

I only drove the Curtin and Newcastle cars on Monday. Would have loved a run in Auckland's car as well, but unfortunately it never ran.


Ergo -
Curtin was OK, but I drove without the seat insert, and that was a big mistake. I didn't know it had adjustable steering wheel position, but it was ok anyway. The addition of a cast seat insert, and maybe lower shoulder harness attachments would lift it to good.

Newcastle was not so good. Pedal box was nice and the steering wheel position ok, but the seat and harnesses offered no support at all, and elbow room was lacking.


Steering -
Curtin's steering was very heavy. Additionally, Hoosiers at low pressure required a lot of steering to get around the track, spoiling the car overall, especially in combination with poor seat support. Vagueness removed all hope of a serious go at the high speed narrow lane changes, but was no issue in the more open sections. Rate seams about right, but effort and loading up with G's killed it.

Newcastle's steering/front suspension has massive compliance oversteer. This causes virtually uncontrollable darting and is quite scary to drive. It does however show that rapid transient response is possible with a 250kg car on Hoosiers! If the darting could be properly timed with the lane changes the car was proper quick with loads of grip and no understeer. The rate was also a little too fast, and in combination with the darting and poor seat support, death grip steering and dead arms came very quickly.


Brakes-
Curtin had the bias a little too far forward. The was some rear locking over bumps, perhaps understandably leading to the setting, but none the less, it was hard to stop it. I never attempted to trail brake much, as I was struggling with turn in accuracy anyway, and didn't need any more complications. Pedal effort etc was good.

Newcastle had an amazingly good pedal feel. Like a rock, and the effort seemed ok as well. Unfortunately steering issues and darting meant serious braking G's could not be achieved with control.


Tyres-
Newcastle had giant Hoosiers, that seemed to have masses of grip, and also good response. Perhaps the wider tread improves the stiffness somewhat, as I don't think they were pumped up especially hard.

Curtin, Hoosier 7" at low pressure = YUK! I would have liked the chance to drive it later with more pressure in them and see if there wasn't a good number lurking in that car.


Engine -
Curtin has a lot of power, but just a little late/high to be really good out of the slower stuff. Maybe if everything else was spot on apex speed might come up enough, but I doubt it. Once in the power band control and response is excellent, but transition from the flat area is savage. Gears shift is good.

Newcastle's engine had reasonable torque whenever requested, but came with light switch control. The gear shift worked OK, but the ergo was pretty poor. Foot operated clutch feels so strange now I'm used to the hand clutch, I didn't use it once underway.


Suspension -
Curtin's car is softly sprung and damped. Not bad, just soft. This trades quite a bit of response for grip and consistency on the rough stuff, where it is very good. I suspect the warp stiffness is not a lot more than the UWAM Kinetics cars, but without the additional pitch and roll springs they have the transient response suffers a lot. All this is not helped by the Hoosiers. Overall I found the car hard to place on the road with any accuracy, but willing to take and hold a set with good lats available. Previous experience would suggest lack of combined corner exit grip is a Hoosier thing, and not any fault with the car. Once straight, power down was good.
The rear was somewhat upset when braking over bumps, leading to excessive front bias, and poor braking G's. Either damping, or perhaps a preload/bind issue in droop.
This car is very close to being as fast as any I think.

Newcastle has a very high rear roll centre causing huge jacking in the rear suspension when pushed. This is quite extreme when combined with a bumpy section, with the car bouncing completely off the ground! Despite control and compliance issues, for a couple of meters here and there I achieved a reasonable set, and the lats are actually OK, even if very difficult to achieve. Any thoughts of trail braking or hard corner exits are quickly banished by control issues.


These two make an interesting pair in some ways.
One might be tempted to say the high weight, yaw inertia, and Hoosier tyres, will limit the transient response of the Curtin car so it can never be really sharp. However, the bigger, heavier and also Hoosier shod Newcastle car had crazy fast darting response, so clearly it is physically possible to make a car this size change direction in a big way!
But how to actually achieve control, stability and fast response at once?


Thanks for the drive guys!
I was hanging out for a go after just watching all weekend.
Great to see the Curtin guys pick up 4 seconds during the day! I'm sure they will be much harder to beat next year.

Pete

[Moreboost]

Cheers for the feedback, just wanted to let you guys know, RMIT's diff was loose as sh*t because we decided to put on a show after enduro on the practice track http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[Goyds]

G'day All

I thought i might weigh in with my experience with electrics over the past 2 years. I know a few people have been curious how they perform in comparison to petrols.

Swinburne has been struggling to regain the powertrain knowledge needed to field a competitive vehicle but we hope to start challenging the petrols in the next year or so.

From a driver's perspective an electric vehicle is both a joy and a curse to drive. The direct and flat torque curve is amazing and inspires confidence however the quietness if very off putting. It is very hard to judge speed on visual clues alone and so with just wind noise braking and entry speeds can be very tricky. We tried to get around this with straight cut gears but it wasn't enough. On the other hand, you can hear what the tires are doing, which is a little odd at first. I'm sure a good driver could learn a lot from this.

The single biggest problem with the Aussie electrics is still weight. Our vehicle is 312kgs without the driver and is exhausting to drive. Also our braking system which was very similar to our 2010 petrol vehicle's, almost completely failed on lap 12 of our first enduro event after the front pads disintegrated. I can honestly say i was relieved that i needed to back off...

On the plus side, as many of you could see, the way the vehicle accelerates, despite it bulk, is amazing - especially from 60+km/h. Our TS_12 vehicle will do 60-100km/h in just under 1 sec at full power. For the competition we ended up backing off our powertrain to around 60% of max torque as we felt our drivers needed more seat time and it was approaching dangerous in our unexperienced hands. As it is, our vehicle is over powered and we intend to loose some weight in the powertrain department for 2013.

I'm sorry we didn't manage to cycle anyone through it on Monday, we haven’t been able to sort out our brakes as yet. Boffin, I hope to give you a go in the next month or so.

If anyone is interested in electrics, feel free to swing me an e-mail. They are very different to petrols and from what we have seen in Europe, can be faster, but need a lot of work to get the best out of them.

A big thankyou goes out to UWA who lent us their callipers for the weekend as well.

See you all at FSAE-A west.

Lloyd

Chief engineer TS_12
Powertrain leader TS_11
lloyd.morrissey@gmail.com

[Rex Chan]

Originally posted by Moreboost:
Cheers for the feedback, just wanted to let you guys know, RMIT's diff was loose as sh*t because we decided to put on a show after enduro on the practice track http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

And you didn't feel the need to return it back to comp spec so other drivers could give you useful feedback?

Edit: great to hear Swinburne Electric will be at FSAE-A West too!

[JulianH]

Originally posted by Goyds:
The single biggest problem with the Aussie electrics is still weight. Our vehicle is 312kgs without the driver and is exhausting to drive. Also our braking system which was very similar to our 2010 petrol vehicle's, almost completely failed on lap 12 of our first enduro event after the front pads disintegrated. I can honestly say i was relieved that i needed to back off...

On the plus side, as many of you could see, the way the vehicle accelerates, despite it bulk, is amazing - especially from 60+km/h. Our TS_12 vehicle will do 60-100km/h in just under 1 sec at full power. For the competition we ended up backing off our powertrain to around 60% of max torque as we felt our drivers needed more seat time and it was approaching dangerous in our unexperienced hands. As it is, our vehicle is over powered and we intend to loose some weight in the powertrain department for 2013.



Our drivers love the electric drivetrain, after a couple of runs, they don't need a screaming engine behind them to know how fast they are going. But our cars were always really loud, maybe that's helping http://fsae.com/groupee_common/emoticons/icon_smile.gif

312kg sounds really a lot. What kind of drivetrain is in that car?

The problem with electric cars is still the limited test time due to a bunch of issues with the drivetrain. But 2012 (especially the AutoX in Germany) showed that Electric cars are now as fast as combustion cars.

Sorry for getting a little bit of topic, but I'm very interested in the Aussie Electric cars, hopefully we will see one of them at an European competition.

[Goyds]

G'day Julian

I suppose that really is the basis of the problem, we didn’t have enough seat time to use the potential of our car. I'm sure with practice a driver would learn to love the electric drivetrain. I know i'm starting to fall for it.

In the long run i think we have learnt what most people already know - Weight kills everything.

[penna]

In reply to a couple of questions asked about the Curtin car.
Peak hp is 80 at the wheels (5 down on last year)this is at 10500 rpm.

Scrub radius is 50mm designed and was around 60mm on the day. As far as I know we run around 20mm of trail.
Tyre pressures were running around 10psi when everyone drove it. These were increased for one of our drivers on the final run of the day to 12 psi which improved the responsiveness and driveability of the car. ( Was previously getting 52.5 and managed consectutive mid 49s with the change).

Thanks for all the feedback guys, it has all been really helpful

[Moreboost]

Originally posted by Rex Chan:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Moreboost:
Cheers for the feedback, just wanted to let you guys know, RMIT's diff was loose as sh*t because we decided to put on a show after enduro on the practice track http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

And you didn't feel the need to return it back to comp spec so other drivers could give you useful feedback?

Edit: great to hear Swinburne Electric will be at FSAE-A West too! </div></BLOCKQUOTE>

No

[Trav]

Hey all,

I drove autocross and the second endurance this year for Monash (red helmet), and also drove endurance and accel last year as well as skidpad and accel in Europe this year. On the car swap day I drove both Sophia and Curtin. I have also had quite a bit of experience in the Monash m10 with a 600cbr.

Sophia:

Ergonomics
The first thing you notice about this car is the terrible ergonomics. I am only 5'9-5'10 and 68kg and yet seriously struggled to fit in this car. Your elbows were squeezed in by the narrow chassis which forced all the steering to be done by your wrists and it significantly limited the amount of steering lock you could use and also how fast you could steer. It was an enormous struggle to make it around the infamous Aus comp hairpin which is there every year. Ergonomics is one of the most overlooked areas in many FSAE cars which can give a huge improvement in lap time and especially driver fatigue in endurance. This area is one of the best aspects of the Monash car (especially the seat as Chris mentioned earlier) and I implore teams to take ergonomics more seriously.
I was also not a fan of the way the Sophia gear shifting was set up with 3 pedals and paddle shifters, needing the clutch for shifting while using the paddle shifters. A simple manual hand shifter and hand clutch is easier to use and involves less motions from the driver, and allows you to keep your feet in the same place at all times.

Steering and Suspension
Apart from the ergonomics making it a little difficult, wow. The steering was nice and light and it was the most balanced and smooth FSAE car I have ever driven. Whatever they have done with their suspension set-up it is awesome. The car would go exactly where the steering was pointed and had almost no roll or pitch but it never felt rock solid either. The damping on this car was perfect. It was extremely composed and easy to drive, but still had a very quick response to inputs. I congratulate Sophia in this area.

Brakes
Very nice solid pedal (though very cramped due to the 3 pedal layout) and had loads of feeling. The brake balance was good but for some reason the car didn't seem to slow down that well before locking a wheel, maybe due to the mass. Very easy to use and get the most out of them for any driver.

Powertrain
Very nice linear engine that just kept pulling through the whole range. The car was very composed at corner exit and you could just plant your foot without having overwhelming power causing oversteer. However i think it could do with shorter gear ratios, as I was able to do the entire track in second gear without it lugging or hitting the end of the powerband. It even felt very powerful idling around the hairpin and it never hunted even once. The tall gear ratios seemed to detract from the power that the engine actually had and it therefore didn't pull quite as hard as I was expecting, though it was still quite fast (much better than the Monash single, quite similar to the Monash m10) and using such little fuel while still being that fast is a great effort.

Aero
Nice job here as well, although not massive wings like Monash and ECU, they definitely work and the downforce is probably about on par with the Monash m10 car. The aero just added even more stability (if that was possible) to the car at high speeds and the grip levels were noticeably higher in the high speed sections of the track compared to the tight sections.

Overall
I think if the hairpin was not at the Aus comp track, this car could easily have blown everyone away, but the ergonomics really downgraded what could be one of the best cars in the world. If the ergonomics was improved, a slight shortening of the gear ratios and maybe a little loss of weight to improve its sharpness, this car could make a significant statement in the European competitions.

Curtin:

Ergonomics
Quite good. I liked the adjustable steering reach to get a preferable position for each driver. There was plenty of room in the high sided chassis (unlike Sophia) for steering and every control was easy to use. The manual shifter on this car was in a reasonable spot, though I think it could have been done like the Monash car and reach all the way to the steering wheel to avoid taking a hand off the wheel for upshifts. Having said that it was definitely the best manual shifter I have ever used, worked every time and was very positive and light. The seat could do with a bit of improvement as I ended up with a couple of bruises on my sides after driving and it could have held me in laterally a little more. Also an adjustable pedal box would allow more drivers to be more comfortable but it wasn't too bad for me.

Steering and Suspension
The steering of this car was on the slightly heavier side, though not much worse than Monash m12. I think I would be just ok for an endurance length but I think it would be beneficial to reduce the weight a little. As mentioned earlier, the scrub radius is too high. I had one moment coming over the hill where I pinched a wheel due to the terrible front brake bias and the steering snapped to full lock without anything I could do. This should not happen, ever. The general feedback though the wheel wasn't too bad and I didn't have any problem finding the limits. The main problems with this car were that the limits were very inconsistent. The balance was pretty good when you were not on the brakes or the throttle, but as soon as you toughed either, the car would pitch a lot. When accelerating with that enormous power the car would pitch so much that the front wheels had no weight on them at all and hence couldn't turn (mass understeer). But while trying to trail brake, it was impossible as the brake bias was so far forward that the front wheels just locked and stole all the front end grip, giving more severe understeer. To manage this car, you had to brake very early and then coast through the slaloms and power out once in a straight line. There is a significant amount of time to gain in the setup of this car.

Brakes
As I mentioned earlier, the brake bias was terrible. The front wheels locked so easily it just destroyed any confidence from the driver. Otherwise the pedal felt solid and I never had any fading problems.

Powertrain
HUGE. The power in this car was awesome. The power curve was interesting, if you were in the low revs, not much happened but then all of a sudden the sledgehammer hit and the car just took off. At first I thought this was a little undesirable but I soon found that with the really nice shifter you could always keep it in the powerband, which was very satisfying and rewarding. Very fast car, it definitely pulled harder than Sophia and Monash m10, and 2011 UTS. I would be interested to know how it compares to Melbourne.

Overall
This car has the potential to be a very good car. Keep the shifter and powertrain like it is and sort out the brake bias and pitching problems and you will be very competitive, though I have my doubts about fuel usage with all that power. You should also do some more driver training and setup work for the acceleration event, as you should win.

Hope this is of use to someone.

[Rex Chan]

Well, MUR 2012 has only 49kW (SAE corrected on the engine dyno, so even less at the wheels), so will be interesting to see how it compares.

Quite a few Melbourne guys (Andrew Gunn, Joel Smith) would like to drive the 2012 Monash car, so once we've fixed our oil pressure/cooling issues, which should be soon, we'll be up for driver swaps in the Melbourne car (as long as insurance stuff works out).

[Shooter]

Fastest lap in the Monash Car goes to Daniel from ECU with 46.977 (from our beacon at the start finish line), we would be very interested to hear his thoughts on our car.