small turbochargers

[A Reinke]

anyone out there able to find small turbocharger information online?

we have a Garret (15?) turbo that is the smallest turbo they make on their website, but we feel it is still too big for a restricted engine. what are your thoughts?

i thought about looking more into ATV turbos as an option. has anyone found anything they are considering? how about you teams that ran a turbo last year...what did you use? what are your experiences?

regards, http://fsae.com/groupee_common/emoticons/icon_smile.gif

~Adam

[A Reinke]

anyone out there able to find small turbocharger information online?

we have a Garret (15?) turbo that is the smallest turbo they make on their website, but we feel it is still too big for a restricted engine. what are your thoughts?

i thought about looking more into ATV turbos as an option. has anyone found anything they are considering? how about you teams that ran a turbo last year...what did you use? what are your experiences?

regards, http://fsae.com/groupee_common/emoticons/icon_smile.gif

~Adam

[Daygo Nighthawk]

Garrett's FSAE sponsorship includes a GT12 turbocharger, and a GT15V turbocharger (variable vane geometry). Contact them for more information on the GT12.

___________________________________
College is a fountain of knowledge . . .
and the students are there to drink.

[PS]

Adam

[PS]

Adam,

The GT12 is for 500cc to 1000cc engines.

[A Reinke]

we have a GT12 and a GT15.

like i said though...we feel its too big for a restricted engine. yes we are 600cc's...but the volume of air we can get into the engine is no where near what they can make stock.

imagine a 600cc turbocharged stock motor...we're talking 150+ HP. FSAE is lucky to see 1/2 that.

~Adam

[Jimboblofski]

that is not strticly true.

For a start you still fill the same volume in the cylinder. if yo did not you would create a vacume when the piston gets to bdc. The problem with the restrictor is that the air speed peaks at a much lower point in the rev range than the bike engines are designed to produce thier peak power figure.

Why is power so important? with the track dimentions we have to race on it is USABLE TORQURE that is required to get a good lap time. If it is just power you are after we produced an engine with 70 bhp (naturally aspirated.) that was from just rebuilding the engine properly.

The advantage of the turbo is that you can move the peak torque value to a mor useable part of the rev range.

This brings me on to final drive gear ratios. a good testing programme will include final drive ratio testing as alot of the driving chracteristics can be changed from these two components.

There are other people that make turbo chargers than garret so why dont you try some where else if they dont have what you want.

[John Oliver Postlethwaite]

gt12 may be for up to 1000cc engines but not ones that rev to 13,500rpm! its far too small.

[VFR750R]

I'm gonna bite.

{Jimboblofski
Member

posted October 01, 2003 09:50 AM
that is not strticly true.

For a start you still fill the same volume in the cylinder. if yo did not you would create a vacume when the piston gets to bdc. The problem with the restrictor is that the air speed peaks at a much lower point in the rev range than the bike engines are designed to produce thier peak power figure. }

I'm not sure what you meant by you can't create a vacuum in the cylinder, but the restrictor definitly decreases the density of air in the cylinder D=m/V. Yes volume does not change, but density and pressure definitly do. Actually in a real engine, there are very few operating points that you get the cylinder to fill up to atmospheric pressure (100% volumetric efficiency), and it takes a no compromises engine with good manifolding...or a super or turbocharger to get over 100%. That means that yes at bdc the cylinder is at a lower pressure then atmospheric which you remember is slightly less then 15psi absolute.

There is a reason that NA cars are only getting 35-38ftlbs of torque and the factory versions are getting 45. It isn't that the manifolds stink, I would be willing to bet most of the top teams could break 50ftlbs without restrictors because we don't have the packaging issues of a motorcycle, especailly the intake manifold.

The air speed thing you said is wrong but by chance is somewhat right, I just don't where to start to fix it.

You should read a good engine book, you defintly don't fully understand what you said.

PS

[Dan Deussen @ Weber Motor]

VFR750-

I was just wondering where you came up with only 35 to 38 ft-lbs for NA cars? I'm pretty sure there are quite a few cars that break the 40 ft-lbs mark.

Now I have another question for you: What would it take to see a good dyno chart of the famous Cornell powertrain? I don't mind posting one of our dyno charts with the hope that other people are willing to share some of theirs.

So here I start:
http://cs.svsu.edu/~dsdeusse/dynochart.JPG

[Eddie Martin]

The guys on our 04 team have been testing with a turbo a lot. They are getting 68 kW and 94 Nm at the output shaft. It's a Honda CBR600 with a garrett turbo, don't know which one.
With an N/A set up they were getting 53 kW and 57 Nm.

Eddie Martin
UOW Racing Alumni

[VFR750R]

I got the 35-38 sp,e teams at competition in 03 and some of the guys I work with that were also on FSAE teams. I realize the best teams can get over 40, but I've never heard of a team getting over 45.

Having me post a pic from 03 dyno testing is as easy as telling me how to post. I don't even know what URL stands for.

[Denny Trimble]

VFR,
You'll need to get your picture up on some public web space (most schools offer this to students), then use the "image" button in your reply (looks like a mountain) to enter the URL (web address) of that image, i.e. http://students.washington.edu/dennyt/bush.jpg

That link would show up as a picture, like this:

http://students.washington.edu/dennyt/bush.jpg

[BIG G]

turbo smurbo, look onto the common pigeon!Lke the finger pointing at the moon, look on the finger and you miss all that heavenly glory.

[Lash]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BIG G:
turbo smurbo, look onto the common pigeon!Lke the finger pointing at the moon, look on the finger and you miss all that heavenly glory. <HR></BLOCKQUOTE>


Am I the only one out there that doesn't get this ???

[Matthew Robinson]

Cornell makes between 85-95hp at our dyno depending on our code and desired boost.

I do not have any dyno charts on hand though.

[Dan Deussen @ Weber Motor]

VFR-

I wouldn't mind hosting and publishing the dyno chart for you on my web space. You can e-mail it to me at ddeussen-at-walbro_nospam_.com (replace the -at- witn @ and remove the _nospam_).

[Dan Deussen @ Weber Motor]

VFR750 just sent me the dyno chart so here it is with his comments.

VFR750: "This is not what we ran at competition (different manifolds, different turbo, no e-wastegate), but is fairly representative of a Cornell powerplant."

http://cs.svsu.edu/~dsdeusse/CornellDyno.jpg

[Chris Davin]

The graph provided by VFR750 is fairly representative of our powertrain. The 2005 powertrain is still under development but I will post dyno graphs in due time.

[Dan Deussen @ Weber Motor]

Chris,

I recall RPM indicators on your '04 dash board that went up to 13k. How high do you guys actually spin the engine on the track? It appears to me that based on your dyno graph, the engine should never be taken past 9k or 10k. Would you mind commenting on this?

[Chris Davin]

Daniel,

Sure, no problem.

We tune our engine for midrange torque, as you correctly identified based on our dyno plot. Judd (VFR750R - a former engine team member) did not have any plots since 2003. Since then we have developed an electronic wastegate control system that improves the high-RPM performance of the motor. Without e-wastegate, at high RPM, the boost drops with RPM because the restrictor limits charge density. So, with a pressure diaphragm, the wastegate closes. The turbo screams but cannot draw in any extra air because of the restrictor. The flow exiting the restrictor goes supersonic and a substantial total pressure loss results. Much of the shaft work through the turbo is effectively wasted heating the charge when the turbo would rather be compressing it. EGT's and backpressure rise and power drops rather sharply.

Our electronic wastegate control system opens the wastegate at high RPM, using feedback control. Opening the wastegate relieves backpressure, lowers EGT's, and reduces turbo shaft RPM. The mass flow through the engine is the same as it would be otherwise but charge temperature and pumping loss are both lower. The result is that the engine holds power much better above the choke RPM. The 2004 powertrain is similar in performance to the 2003 powertrain below choke, but is able to hold its power much better at high RPM.

That said, we do not typically operate the engine near the redline. The redline in the stock bike is 13,200 RPM and we have no reason to artificially lower it (in case driver needs to stretch a gear out, etc.) But even with e-wastegate our usable powerband does not extend all the way to redline.

I hope that answered your question.

[Matthew Robinson]

"The redline in the stock bike is 13,200 RPM and we have no reason to artificially lower it (in case driver needs to stretch a gear out, etc.) "

Or miss a shift hehe

[Fred the Gypsy]

And they say that no NA motor can break 45 ft-lbs. Been doin' it for a while.http://www.77spider.com/images/gtmotorsportspower.jpg

[VFR750R]

I stand corrected. Your curve looks really good! You guys did a great job with that engine. What do you run by the way(CBR, YZF, ect.)?

[BeaverGuy]

Oregon State University
http://web.engr.oregonstate.edu/~gilletjo/2002_Dyno.JPG
This is dyno graph from 2002 when they were doing testing for a variable length intake. They did tests with 10 to 34 inch intake runners on a Honda F1 engine. Using an intake of that length in 2003 on a ZX6R they got a similar curve, shifted a little lower in the RPM range so they didn't produce as high a horsepower number.

[Nick McNaughton]

Chris,

That's an incredible torque curve, you guys must really design for low end. The rest of us spin things a little harder and go for torque up around 9k. From the look of things, you're already on boost at 4500rpm because you're 10ft-lbs up on a good atmo engine.

If you don't mind me asking, are you actually on boost that low, or is that low rpm torque a result of some other factor?

Cheers,
Nick

[Chris Davin]

Nick,

Yes, that torque is from of the turbo.

[Justin Hodge]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Fred the Gypsy:
And they say that no NA motor can break 45 ft-lbs. Been doin' it for a while.http://www.77spider.com/images/gtmotorsportspower.jpg <HR></BLOCKQUOTE>

LTU produces damn near the same torque curve with the honda 600 f4i engine.

[John Bucknell]

Careful about racin dynos (beatin my dead horse here)...

They are very finicky, and two different dynos rarely yield answers of similar magnitude for the SAME ENGINE (unless they are motoring AC dynos, calibrated exactingly - even then we have problems about test conditions comparing manufacturers' data). Also, beware using a SAE J1349 correction factor greater than +/- 4% as it doesn't correlate to anything.

[waz]

UOW Racing ran a turbo engine at this years australian comp and I believe it was the best motor there. Our dyno graphs look similar to those posted by Cornell.

This is however just half the story to the turboed engine. In the real world turbo lag will be the greatest challenge to overcome.

Chris Davin: I would love to talk to you about your experiences with other turbos, runner lengths, intercooling etc. It is a great shame that University of Wollongong have choosen not to come to the US this year and compete. I would have enjoyed comparing our cars.

Warwick
Engine Group Leader 2004
UOW Racing
warwickbeynon@hotmail.com

[Frank]

well... we hosed your car, in both acceleration, and visably on the track

naturally aspirated 76hp

http://www.uq.edu.au/fsae/sae_a_2004/images/engine.jpg

dyno run performed by motec queensland
http://www.uq.edu.au/fsae/uq_engine.jpg

[Denny Trimble]

LOL... right on Frank. But, what happened in the autocross? Looks like that's the only dark spot on your scorecard...

[Eddie Martin]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Frank:
well... we hosed your car, in both acceleration, and visably on the track <HR></BLOCKQUOTE>
Frank,
I don't know what you have been smoking. http://fsae.com/groupee_common/emoticons/icon_biggrin.gif
You guys were 4 seconds slower in autocross.
In the first enduro uow was 10 seconds faster than uq uncorrected and 10 seconds slower corrected time.
In the second enduro uow were 81 seconds faster than uq uncorrected and 29 seconds faster corrected.
The first time the uow 04 car, roger, ever did an acceleration run was at the competition and it was with no launch and traction control, i think 4.25 sec is pretty good in the circumstances. With the same powertrain package in the 03 car it was doing 3.8s.
I don't really see how you "hosed"� us on those figures.

[Frank]

((takes a big hit from the pipe))

your car did the 5th fastest acceleration time on the day.

we did the first four fastest.

and remember there's a difference between acceleration times using transponders placed at the rear of the car, and using optical timing (which was used at the comp)

i meant in the "straight line" bits of the track.

im about to become the most hated person here.

turbos in fsae are gay, heavy, use more fuel, don't make much more power, introduce lag, and at best don't make the car any faster in acceleration... at worst they make the car damn hard to drive. Turbos make the project more costly, risky, and can't serious be considered a good decision whilst considering the "concept" of the prototype.

anyhow we only got 15/30 for "power train judging" this year, so i suppose our team know crap all, and some newbie on our team will masturbate about turbos all over the department until he gets the funding to do one, just 'cos "'gong's got one"

ps our first acceleration run of 4.22 didn't use traction control (just a tire warming run)
i can post the logs if you like

[andrewd]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Frank:
((takes a big hit from the pipe))

turbos in fsae are gay, heavy, use more fuel, don't make much more power, introduce lag, and at best don't make the car any faster in acceleration... at worst they make the car damn hard to drive. Turbos make the project more costly, risky, and can't serious be considered a good decision whilst considering the "concept" of the prototype.

anyhow we only got 15/30 for "power train judging" this year, so i suppose our team know crap all, and some newbie on our team will masturbate about turbos all over the department until he gets the funding to do one, just 'cos "'gong's got one"
<HR></BLOCKQUOTE>

sounds like someone is jealous?

dude dont make silly comments you dont have the balls to back up,

ok yes the turbo used more fuel, only because we were making more power,

second the results posted by say show we were faster in both acceleration and enduro / autocross why try and say otherwise?

and lastly our forced induction package had just as good if not better throttle response than the NA package, meaning it was easy to drive and had no LAG problems http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Denny Trimble]

I think the results show UQ focused on accel testing and Wollongong focused on AutoX / Endurance testing. Who's to say what would have happened if each team had another month to test the other events...

We'll never know. All we know is what each team did with its resources that year. I think both cars are exceptional!

Edit: dboi, check your facts. How is your 4.257 run better than UQ's 4.055 run?
http://www.sae-a.com.au/fsae/downloads/2004_Competition_Results.xls

[Handles]

i think dboi is sharing the peace pipe with Frank http://fsae.com/groupee_common/emoticons/icon_eek.gif

but anyways, as denny said, uq focussed on accel and other teams spent more time focussing on the autox / endurance

correct me if im wrong though, perhaps the rules have changed..back in my day...the object of the comp was to design and build a small autocross car http://fsae.com/groupee_common/emoticons/icon_confused.gif has this changed to designing and building a drag car http://fsae.com/groupee_common/emoticons/icon_frown.gif damn you guys!!!....you wasted a whole year building the wrong thing http://fsae.com/groupee_common/emoticons/icon_mad.gif

but seriously, congrats to uq, they have got the accell runs down pat now, tho a hell of a lot more testing and track time is always the winner
i still dont see how "uq hosed the gong on the track"..please explain?? (to quote one of your fellow stateswomen..who may or may not be smoking the peacepipe with Frank) http://fsae.com/groupee_common/emoticons/icon_razz.gif

maybe i smell a sae state of origin in the making http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[VFR750R]

wow, this is the first time I've heard the "my car is faster then your car" rant in here. Remember that the competiton is more then straight lines, and also don't bash other peoples cars or designs. You end up looking stupid. By the way, I think our 03 (turbo) car won fuel economy.

[Sam]

pass that dutchie frankie honey... I'll have a toke too.

might i just add that we have never taken the head off that engine. the block has had no internal work whatsoever.. oh yeh, and how much time did we spend on a dyno.. not whole lot http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

but come on, we are just really lazy and won that event by pure chance.. http://fsae.com/groupee_common/emoticons/icon_smile.gif

i still can't sit down after the "bashing" we got from the design judges at FSAE-A

next point. i think we spent the grand total of a afternoon fine tuning our accel runs. we did spend most of our testing efforts driving around corners. our guys did a awesome job driving our beast but their racing experience pretty much amounts to a few FSAE comps..

final point.. heal the world.. make it a better place.. http://fsae.com/groupee_common/emoticons/icon_smile.gif

p.s. me no likey big snail..

[VFR750R]

I can't speak for UOW but Cornell powerplants are internally unchanged. Every year we discuss doing internal mods, but every year we decide against it due to cost and limited testing time (we do a complete engine rebuild in about 40 hours, how many times are you going to do that to prove one set of pistons is better then another).

We do have lot of dyno time, our budget is big enough to have a seperate dyno engine, turbo and manifolds. This allows us to co develope our engine package with the car in the spring. Most of that time is spent troubleshooting the ECM though.

[Frank]

ok i stop stirring the pot now

i think gong's car is always cool, and fast

i just hate snails in fsae

IMO if you focus the resources elsewhere, you'll go faster

there's some newbie on our team spouting about his proposed turbo.. i hate that

[Denny Trimble]

Every year our new engine guys want to do a turbo... then it takes them 2 months to figure out how to set up the current engine package on the dyno. Reality check...

[Frank]

pmsl..

our newbie was telling me how he was going to "match the manifolds"

he knows every tip available at your local 7-11

he'd never even looked at the engine LOL http://fsae.com/groupee_common/emoticons/icon_smile.gif

i've had the complete jack with our academics..

guys come along and ask academics if they can do a thesis on the car, and the academics say "yeah suuuure..." translated as "that's one more student i don't have to supervise.."

i think the team manager should have the balls to say

"uhhh, excuse me i don't know you, you don't know anything about this competition.. %^$# off"�

but they (optimistically) think "maybe he will make a few widgets"

invariably you get screwed by these people.

once your team gets even a scent of success, "legends" appear out of the woodwork each year

Maybe this distain is what you get after being on a team for four years. Four years of cleaning up after people's mistakes.

[rjwoods77]

40 hours? To do what exactly?

[Tony K]

Ah yes... cleaning up after people's mistakes. You've succesfully summed up my winter break last year, this year, and for many years to come. Add spring break and summer in there too, and that's what I do for fun.

[BryanH]

Thanks for the very funny posts and reality check, Frank.
I am also guilty of trying to jump on the turbo bandwagon. Rotor and I had "discussions" re tuturing a couple of young guys on turbo WR450 but he is more sensible than me. resources are better spent removing 15kg & testing wings.
Mychron data logs from enduro show that the werribee track is a series of drag strips with RO4 only pulling 1.15 lateral g's (over 1.65g on test track). Not an ideal fsae track.
W,gongs engine package was mightily impressive, lag free and well mapped. I wonder if roger ramjet would have been anywhere near RO4's laptimes sans 90bhp?
btw powertrain judge caned RO4 as well, "not complex enough, and probably poorly mapped"
Car ran consistant 40.3's and used 2.55litres!
The "I want to do a thesis on the car" stunt happens everywhere, tell em to do it on last years car.
Please don't come the "if only we could drive" excuse, If Mark Winterbottom was only a few tenths faster than your guys that is as fast as it will ever go.Take notice of what Mark said about the handling and get the 9" angle grinder out......make sure the webcam is on.
Merry Christmas Bryan Hester

[clausen]

lol,

did you map it Bryan?

did the RMIT lads test wings?

did you get my pm?

[VFR750R]

It can take less then 40 hours with 2 people, but in man hours terms it's about 40. 10 hours to take the engine apart. 5 to clean it. 10 to inspect old parts and prep new parts. And 10-15 to put it all back together. A motorcycle mechanic with years of experience probably could do it in less, but once you figure out what you need and order parts. Oops I forgot to do that, kinds of things, you're looking at 40 hours. By the time you take it off the dyno 1 hour and reinstall, close to 2, there's even more time involved.

I think I remember you being into singles, so you can cut this in half, but I wouldn't say more then that.

[Frank]

"If Mark Winterbottom was only a few tenths faster than your guys"

lol

i wish

it seems Mark actually enjoys a ridiculous amount of understeer

Thanks Bryan,

i guess i do sound jealous, perhaps i am a bit, but I know a naturally aspirated engine can kick it down the straights just as good as a turbo.

my point really is that one should be allocating resources carefully, and i doubt many people experienced with the engine would agree that turbos are the ^$%$

I think its time sae-a get some "experienced"� judges

experienced in making these cars, or any open wheel race car for that matter

I noticed Frank Roske, from Strausland, was judging at formula student

[Sam]

or some clown that asks you why you haven't done CFD on a radiator shroud..

oh sure, our team has a supercomputer and a team of 100 trained monkeys.

[BeaverGuy]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> or some clown that asks you why you haven't done CFD on a radiator shroud..

oh sure, our team has a supercomputer and a team of 100 trained monkeys.

Sam Graham
Random Stooge 2004
UQ Racing <HR></BLOCKQUOTE>

Hey, I'll be running CFD on our radiator and I have neither 100 trained monkees or a supercomputer.

[stevep]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BeaverGuy:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR> or some clown that asks you why you haven't done CFD on a radiator shroud..

oh sure, our team has a supercomputer and a team of 100 trained monkeys.

Sam Graham
Random Stooge 2004
UQ Racing <HR></BLOCKQUOTE>

Hey, I'll be running CFD on our radiator and I have neither 100 trained monkees or a supercomputer. <HR></BLOCKQUOTE>

just one trained monkey and 100 supercomputers then?

[Sam]

I'm not having a go specifically steve but modelling flow through an actual radiator core is not a simple business and i doubt it can be done accuratley without the aid of the afore mentioned tools. and before that happens you must understand the inlet flow to your radiator, i am guessing that it's not sitting in front of the nose of your car in virgin air http://fsae.com/groupee_common/emoticons/icon_smile.gif
so that is why i say that CFD on a shroud is a waste of time for an FSAE team. I have done extensive physical testing on our cooling systems and made test rigs and the like and gained loads of useable data. We test in 40 deg heat in Queensland and our comps are often that hot too. we never have problems.

I know some judges like to see computer studies but physical testing will provide you with a system that works http://fsae.com/groupee_common/emoticons/icon_smile.gif

[stevep]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Sam:
I'm not having a go specifically steve but modelling flow through an actual radiator core is not a simple business and i doubt it can be done accuratley without the aid of the afore mentioned tools. and before that happens you must understand the inlet flow to your radiator, i am guessing that it's not sitting in front of the nose of your car in virgin air http://fsae.com/groupee_common/emoticons/icon_smile.gif
so that is why i say that CFD on a shroud is a waste of time for an FSAE team. I have done extensive physical testing on our cooling systems and made test rigs and the like and gained loads of useable data. We test in 40 deg heat in Queensland and our comps are often that hot too. we never have problems.

I know some judges like to see computer studies but physical testing will provide you with a system that works http://fsae.com/groupee_common/emoticons/icon_smile.gif <HR></BLOCKQUOTE>

so you're saying you need 100 trained monkeys and 100 supercomputers?

hell, you may even end up with a scramjet with all of them working!! http://fsae.com/groupee_common/emoticons/icon_smile.gif

Steve Patrick
Uni Of Melb FSAE

[waz]

Firstly. What has happened to the spirit of the FSAE competition! The event is about learning and gaining valuable skills which put us in a good position for employment as engineers. I have seen serious bitching in this topic.

I completed a thesis study on developing a engine package for SAE. It was primarily aimed at developing a smaller lighter engine package of similar power output to the NA 600ccs. It basically came to a halt when I realised the smaller 400cc 4 cylinder engines were almost as heavy as the 600cc and of lower compression ratio.

I will not tell you UOW had the best solution to FSAE. We had a very powerful engine package and it went hard on the track set for us this year. It by no means cleaned up the event.

I saw many excellent cars at the comp for me highlights were.

RMIT low weight single cylinder, small wheels. Definately thinking outside the square with a fresh approuch and it is working well as shown by there awesome speed on track.

UWA The sweatest sounding motor in my opinion. Super quiet and realy refined, all over power. Good vehicle balance.

UQ Great looking car and smacked it in a straight line. (yes I was dissapointed you beat us in accel but hey we crashed our car on the test track attempting to set up the launch control and were not well prepared for that event. This is what happens as building a car is such a huge task. Every team has its challanges. It is how you overcome them that makes a great team.)

Auckland Although heavy that car sat beautifully on the track.

Anyway back to the turbo none turbo debate.

Every team should do the math on air flows before making a discission on engine choice and turbo / non turbo. N/A can theoretically reach the restricted condition but from our experience the pulse effects limit max power to just below restricted air flow.

The turbo will provide more air flow to the engine at lower rpms and also smoothes the pulses some more air is available.

Conversely it is more complexity and potentally will create lag and not be driver friendly.

We had to do a huge amount of work to overcome lag and to change a NA engine to be sutiable for turbocharging. Yes expect to use more fuel on track too as the laws of physics are at work, the engine is heavier and is making more power so, more fuel. Also more power means heavier drive train.

Does the car overall have more power but go slower due to weight of the car? Is the cg low?

From my experience with the team the worst thing a team can do to its members is say no to there ideas. Say yes let them test it and then evaluate its potental. The FSAE judges seem to like change for the sake of it and are not as impressed with simple effective design solutions so these must also be considered as design points are also important to winning a competition.

WAZ

PS. RMIT might be on to something. What about a turbo single or 250cc inline 4?

[A Reinke]

Wow, my old old post still partially alive. Very cool to see everyone posting dyno graphs from their setups.

We did end up finding a turbocharger other than a Garrett to use and it worked out okay for the most part, but we had some reliability issues, probably due to oil feed/drain, which with more dyno and run-time, could be sorted out. Regardless, here's our setup and graph:

'02 Suzuki GSXR 600
Completely Stock
Dual Stage Fuel Injection
BorgWarner KP35 Turbocharger
Intercooled

http://www.supermotors.org/getfile/124042/original/2004%20dyno%20run%202.JPG

We were still new at figuring out the dyno software and control. Our dyno had a simulated driveline which was a chain going back to the a sprocket on the dyno shaft. We're unsure of the driveline loss it created. Wastegate was intentionally opened to limit the boost levels. 90.5 HP @ 8500 and a large chunk of the map above 40 ft-lbs of torque. 8)

Other pictures of our engine components and video of it running here: http://www.supermotors.org/registry/vehicles/detail.php?id=1538&s=17790#content

I wish I had lots of time and do this again! Enjoy it while you guys get to do it!

~Adam

[Daves]

Adam (A Reinke),

Is the horizontal axis time, not rpm? Good job getting that much power!

The following is a look at our 2004-05 FSAE power and torque curve (F4i). Any suggestions on how to get more power? I'd like to know how Georgia Tech gets so more torque (52 ft-lbs?).

http://www.geocities.com/fif4183/images/2004-05letourneau.txt

[threehondas]

Reinke,

Your dyno graph shows rpm increasing at a non constant rate. This can be really misleading for comparision purposes. There should be setting on your dyno for contant acceleration. If I change the acceleration rate of a dyno pull my graphs change dramatically... assuming your using a waterbrake and not just inertia.

Bruce
http://engsoc.queensu.ca/formulacar/engine/

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by A Reinke:
Wow, my old old post still partially alive. Very cool to see everyone posting dyno graphs from their setups.

We did end up finding a turbocharger other than a Garrett to use and it worked out okay for the most part, but we had some reliability issues, probably due to oil feed/drain, which with more dyno and run-time, could be sorted out. Regardless, here's our setup and graph:

'02 Suzuki GSXR 600
Completely Stock
Dual Stage Fuel Injection
BorgWarner KP35 Turbocharger
Intercooled

http://www.supermotors.org/getfile/124042/original/2004%20dyno%20run%202.JPG

We were still new at figuring out the dyno software and control. Our dyno had a simulated driveline which was a chain going back to the a sprocket on the dyno shaft. We're unsure of the driveline loss it created. Wastegate was intentionally opened to limit the boost levels. 90.5 HP @ 8500 and a large chunk of the map above 40 ft-lbs of torque. 8)

Other pictures of our engine components and video of it running here: http://www.supermotors.org/registry/vehicles/detail.php?id=1538&s=17790#content

I wish I had lots of time and do this again! Enjoy it while you guys get to do it!

~Adam </div></BLOCKQUOTE>

[threehondas]

Do you rebuild you engine every 40 hours of running or does it take you 40 hours to rebuild it?


<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by VFR750R:
I can't speak for UOW but Cornell powerplants are internally unchanged. Every year we discuss doing internal mods, but every year we decide against it due to cost and limited testing time (we do a complete engine rebuild in about 40 hours, how many times are you going to do that to prove one set of pistons is better then another).

We do have lot of dyno time, our budget is big enough to have a seperate dyno engine, turbo and manifolds. This allows us to co develope our engine package with the car in the spring. Most of that time is spent troubleshooting the ECM though. </div></BLOCKQUOTE>

[A Reinke]

Dave,

Yes our X axis was time, not RPM. RPM is in the graph there as it's own line, so it's confusing at first, but you can match things up okay.

I wish I had that laptop we used to record the dyno runs on...I'd fix the graph!

~Adam

[Stevey]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by John Oliver Postlethwaite:
gt12 may be for up to 1000cc engines but not ones that rev to 13,500rpm! its far too small. </div></BLOCKQUOTE>

engine speed is irrelevant, only airflow matters, airflow is directly related to horsepower, with the restrictor, we don't make an awful lot of power, so the GT12 would perform admirably for most of the engines we use

[VFR750R]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by threehondas:
Do you rebuild you engine every 40 hours of running or does it take you 40 hours to rebuild it?


<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by VFR750R:
I can't speak for UOW but Cornell powerplants are internally unchanged. Every year we discuss doing internal mods, but every year we decide against it due to cost and limited testing time (we do a complete engine rebuild in about 40 hours, how many times are you going to do that to prove one set of pistons is better then another).

We do have lot of dyno time, our budget is big enough to have a seperate dyno engine, turbo and manifolds. This allows us to co develope our engine package with the car in the spring. Most of that time is spent troubleshooting the ECM though. </div></BLOCKQUOTE> </div></BLOCKQUOTE>

40 hours to rebuild

We'll go through 2-3 dyno engines a year (often stupid mistakes) and one engine goes in the car for Feb 1 and that lasts until we put in our competition engine 2 weeks before competition. The competition engine usually lasts the whole next fall testing as well.

our test schedule (snowfall permitting http://fsae.com/groupee_common/emoticons/icon_wink.gif is about 2 hours of engine run time M-F and 5-6 hours of run time on sat and sunday or 20 hours a week. If we run every day from March 15th on (semi realiistic) our first engine gets 120 or so hours and usually is taken to competition as a back up. Our comp engine gets ~20 hours before competition (if it was going to blow, it'd do it by then) and then up to 150 more in the fall. Minus days the car is broke or it is raining (maybe 20-25% of the time).

We've never just blown a engine in the car, although we used to have terrrible trouble with FZR transmissions, and we blew one in Fall 02 from a oil starvation issue related to a bad used turbo dropping oil pressure to unsafe levels. Anyone at Toronto fall 02 was witness to it.