ALL TURBO/SUPERCHARGED TEAMS - PLEASE READ

[310Turbo]

Hi,

My name is Cam Thai and I coordinate the FSAE turbo sponsorship for Honeywell. I would like to get a better feel for how forced induction is impacting the FSAE competition.

Please post if your team used forced induction (supercharged or turbo) and whose equipment you used. If you attempted to run a turbo/supercharger but could not, what prevented you from doing so? Are you planning to go forced induction again in 2006?

Lastly, any information you feel would help us better support our teams in future competition would be appreciated.

Best regards,

Cam Thai
AVNT Product Engineering
Honeywell Turbo Technologies

[310Turbo]

Hi,

My name is Cam Thai and I coordinate the FSAE turbo sponsorship for Honeywell. I would like to get a better feel for how forced induction is impacting the FSAE competition.

Please post if your team used forced induction (supercharged or turbo) and whose equipment you used. If you attempted to run a turbo/supercharger but could not, what prevented you from doing so? Are you planning to go forced induction again in 2006?

Lastly, any information you feel would help us better support our teams in future competition would be appreciated.

Best regards,

Cam Thai
AVNT Product Engineering
Honeywell Turbo Technologies

[Jersey Tom]

Hey Cam.

I'll give you our thoughts as to why we do not run forced induction, despite the fact we've had two brand new Garrett turbos sitting around our shop for years.

At the moment with our 464lb (Detroit official) car and naturally-aspirated F4i making 67hp, we are already traction limited. If anything we're working first on getting as many of those 67 horses down on the ground, and don't see the need for messing with a turbo and making our driving platform less controllable.

In addition, the team that won the acceleration event this year, Texas A&M (Big XII represent!), ran naturally-aspirated.

So unless say some representative from a turbo maufacturer were to illustrate to us why it would be to our benefit to go with forced-air induction, we will probably stay with what we have definately for '06 and possibly for '07.

Hope that helps!

[Kamil S]

While teams like Cornell manage to do an excellent job running a forced induction application, I still find it somewhat discontenting that you may not use a liquid coolant for the intercooler. While an air-air heat exchanger works, it just takes away from the essence of the application (in my opinion). It's compressed AND cold that brings you the best results. Considering the existing restrictions that limit the gained horsepower (besides the time required to design an application and the added weight to the vehicle), I would say it is more feasible to go with a naturally aspirated engine. For starting teams at least? http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[James Waltman]

I think that Mark Donohue's quote is:
˜If you can make black marks on a straight from the time you turn out of a corner until the braking point of the next turn, then you have enough horsepower'

Cam,
Our 1995/96 car had an IHI. It was too large and pretty slow to spool. I think the power basically doubles within a few hundred rpm when it kicks in.
Our 1998 car had a GT12. It ran on M85 and was very fast by all accounts.
We tried to run the GT12 for 2004. Our problem was massive amounts of oil pumping through the turbo and into the plenum. After some email conversations with Kirk (while he was still a student) we got it under control a little. We were still not comfortable enough with it to run it in Detroit.

When we called our technical contact (Jeff Steiner) looking for help with the oil problem I guess he basically said ˜Yeah, they leak' but he didn't have any real suggestions. We asked him about the carbon seals and he couldn't help us.

If the teams had some help with the oil leak problem that would be great. That you are even asking here is cool. I think that having Kirk on the inside now should make things a lot easier for future teams. I know that you guys are working on some other stuff to help out the teams that want to run a turbo – keep it up.

[raska]

We just recieved a GT12 from you about 2 weeks ago for use in the 2006 car. We haven't got it organized on the dyno quite yet but hopefully that will come shortly. Right now a big holdup is money for everything else. So far our dealings with you have been excellent. We'll report back when we have a chance to have some fun with it.

[The X Factor UCV]

Mr. Thai, we are from "Universidad Central de Venezuela", as we spoke before, we used a GT12 for our first formula, running a YZF R6 2004, and we did great, We are more than pleased with the result and our 86 BHP at the Dyno!!!.

For '06, our goal is to force air induction again, not only because of our horsepower thirst, but to improve our desgin from last year, such as the cooling and lubricating system for the turbo. These in addition with some major studies that are being done in the powertrain system in our team, that will hopefully turn out in better results than last year.

The X Factor

[Chris Davin]

Cam,

Email me if you'd like to talk.

cdd25 AT cornell DOT edu

[310Turbo]

Guys,

Thank you for the candid responses, they're very much appreciated. I'd like to hear from more teams when people get a chance to post.

Thanks!

[310Turbo]

Does anyone know how many teams went forced induction last year?

Thanks,

Cam

[markocosic]

We've yet to enter a team, but have discussed forced induction and would offer the following comments:

1) You can choke the intake restrictor with a normally aspirated 600 over a fair portion of the rev-range. At best, force-feeding the same engine allows you to choke the engine over an even greater rev-range at the expense of added weight, fuel-consumption and development time.

(more to be gained if using a smaller engine)

Granted, most cars cannot spin their wheels at 60mph in a straight line, but a well developed naturally asthmatic 600 has no problems lighting up the rear wheels when negotiating tight bends. Given that most of the competition /is/ tight bends, what advantage does the extra power give you?

2) An inexperienced driver will find a big naturally aspirated engine or positive-displacement forced-induction engine easier to drive on the limit than any non positive-displacement forced-induction engine. Our FSAE drivers would count as inexperienced!

3) Finding a turbo suitable for the application is difficult. If you take the Garrett offerings, although they're the right size in terms of mass airflow they don't have the right compressor side oilseals and the compressor/turbine designs are "unrestricted passenger car diesel engines" not "restricted race engines". FSAE cars want something more like a WRC car tubocharger than a diesel eurobox turbocharger.

If the rules allowed a throttle on the outlet of the turbo rather than the inlet, the capacity limit was 250cc rather than 600cc and/or turbos with suitable seals and turbine temperature ratings were available you'd probably see a whole load more of them.

At the minute they're not "mandatory" to be competitive and there's a large "activation energy" in terms of development time before the turbocharged engine is better than the naturally asthmatic one.

[Z]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by markocosic:
... but a well developed naturally asthmatic 600 has no problems lighting up the rear wheels when negotiating tight bends. </div></BLOCKQUOTE>

This idea of "too much power" (at slow speeds) was also expressed by Jersey Tom as a reason for not going turbo. The problem is NOT "too much power" - it is "too little rear grip"! I've asked this before, but once again; Why are FSAE'ers the only rear-drive racecar designers that aim for a 50:50 weight distribution? Put a bit more percentage on the rear tyres and they will take a lot more horsepower out of those slow corners.http://fsae.com/groupee_common/emoticons/icon_wink.gif

I agree that turboing an engine can take away development time from other more important aspects of the project. So maybe not for a small first or second year team. But after that I reckon it should be somewhere in the program. It is not that hard - many a boy has left school at 15 and turbo'ed half a dozen cars by the time they are 20. A contingency plan to go N/A if the turbo doesn't work is also straightforward (ie. have a N/A ECU map ready beforehand).

A well sorted turbo on a restricted engine should make the car easier to drive (electric motor torque curve). It should also improve fuel efficiency rather than hurt it - that's why all those "diesel eurobox"s run them.http://fsae.com/groupee_common/emoticons/icon_smile.gif

Z

[Jersey Tom]

My nickname is 'Z'..

I'd say most go for 47/53. But still, so much of what we do involves controlled cornering at relatively low speeds. You could do the '05 auto-x course in 1st gear.

Turbos are cool. There's no doubt. But for us anyway, with fairly limited resources as it is, we just don't see the cost/benefit trade off as being such that we can fully experiment with it. Probably not this year anyway.

Our goal is first to be able to accurately control and tweak the power being dumped to the wheels. Then maybe we'll toy with the turbo route. Control then power, not the other way around.

[Z]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Jersey Tom:
Control then power, not the other way around. </div></BLOCKQUOTE>
Yes.

Z

[Charlie]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Z:
Why are FSAE'ers the only rear-drive racecar designers that aim for a 50:50 weight distribution? Put a bit more percentage on the rear tyres and they will take a lot more horsepower out of those slow corners.http://fsae.com/groupee_common/emoticons/icon_wink.gif
</div></BLOCKQUOTE>

My question to you is who says they do??? We never did. never. We always had a fairly significant rear weight bias. I've rarely if ever seen a FSAE car that had a 50:50 designed weight bias; although many are close (47/53, 45/55).

Jersey Tom, if you could do the autox in 1st gear, then you screwed up on your gearing, because you've got 5 or 6 of those things, and you aren't restricted to any final drive ratio. http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Erick Scarpone]

We don't really know what is to have a normal aspirated FSAE engine as we were a first team and started right out with the GT12 turbo, we had problems making it stop oil leaking...and we did notice some problems in the air intake, at some points the engine just wasn't getting air, we run it with an intercooler and put several pressure gauge on it at several points. We been noticing some -10psi up to -20psi at some points of the rpm as we have notice some +5psi, we know that we have some oil in the intercooler that went upstream of the turbo to the intake, were still interpreting this data. If anyone have some pointers??
As to much power, we been practicing with it at our small parking lot and we started with cones 7 meters apart from each one on the course and right knowe were doing it at 4 mts it only took our drivers two days getting there doing best times than before.
We looove the power we got 86HP and want to go for more next year.
Currently there are 3 power team thesis, one for the restrictor, the intercooler and the exhaust system. Will post some data and some interesting conclusion in a couple of months.
After the weight distribution, I know they did something with bathroom scales but I wasn't there when they did it so I cant help you right know with that, will ask.
I do see that we skid to do the tight corners, it's lot of fun but I guess we lose time in there.
I'm not really sure they skid because they want to, they need to or they loose control of the car. All do they don't usually touch the cones

[Matt Gignac]

We've been running Garrett turbos for the past three years at McGill, and we've been quite satisfied. As a result of the turbocharged engine package, we have a car that is a lot more driveable due to the wide power band, and have managed to make the setup somewhat reliable.

Our only issue is with oil consumption. We've adressed this by restricting oil flow to the turbo, which does away with a major part of the oil consumption, and this year by modifying the center housing to use spring loaded graphite-reinforced PTFE seals from Mcmaster in series with the stock seal. This worked like a charm until the our poor little ptfe seal fell to pieces.

I've heard that certain australian teams have been given prototype carbon seals for the gt12 and gt15v. Are there any plans to offer this to all teams? With proper seals designed for our turbo as opposed to jury-rigged, we're pretty sure we can do away with oil in the intake.

Matt Gignac
McGill Racing Team

[raska]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Chris Davin:
Email me if you'd like to talk.
</div></BLOCKQUOTE>

If you're willing to talk publically at all, for the benifit of the community it would be appreciated. I'm sure I speak for most of us when I say we'd all like to hear what Cornell has to add to this discussion.

[Z]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Charlie:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Z:
Why are FSAE'ers the only rear-drive racecar designers that aim for a 50:50 weight distribution? Put a bit more percentage on the rear tyres and they will take a lot more horsepower out of those slow corners.http://fsae.com/groupee_common/emoticons/icon_wink.gif
</div></BLOCKQUOTE>

My question to you is who says they do??? We never did. never. We always had a fairly significant rear weight bias. I've rarely if ever seen a FSAE car that had a 50:50 designed weight bias; although many are close (47/53, 45/55).
</div></BLOCKQUOTE>
I've just been reading RaceTech's piece on the '05 US FSAE. Four cars got the major coverage - Cornell, UWA, Helsinki, and Uni Simon Bolivar. All these are "standard" cars, and were said to have "impressed the Design judges".

Cornell's and Helsinki's are turbocharged in-line fours with Helsinki's putting out a claimed 113bhp at the crank. Both Helsinki and USB (F4i) are quoted as having "50-50 weight distribution", and "The evolutionary Cornell car had a more rear weight bias to improve traction", but no mention of how much (almost equal sized tyres suggests not much). No F:R figure for UWA.

I don't want to start another rant here, but to a novice team doing some "benchmarking" it would seem that a "standard" car (ie. spaceframe, 600cc in-line 4...) with 50:50 weight distribution is definitely the way to go. The benefits of a rear weight bias, which are considerable, never seem to get mentioned.

I should note that there was a postage stamp sized coverage of RMIT/Tokyo Denki cars, with the comment that "The single cylinder advantage was almost, but not quite, stated". So no point going down that route... http://fsae.com/groupee_common/emoticons/icon_smile.gif

Z

[Chris Davin]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by raska:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Chris Davin:
Email me if you'd like to talk.
</div></BLOCKQUOTE>

If you're willing to talk publically at all, for the benifit of the community it would be appreciated. I'm sure I speak for most of us when I say we'd all like to hear what Cornell has to add to this discussion. </div></BLOCKQUOTE>

Martin,

With my comment, I was thinking more like if Cam had any specific questions that were beyond the scope of what he originally asked for, he could feel free to email me for my opinions. But, since you asked, I'll post a few remarks.

First of all, I think Cornell has been running a turbo for almost ten years and it's fair to say we're quite happy with the design. I won't be running next year's engine team but I would say it's a good bet we'll continue to run a turbo. As has been pointed out, turbos have plenty of pros and cons. Cornell thinks the pros outweigh the cons, or we wouldn't have run one. Other teams disagree, and that's fine - if competition consisted of 140 identical vehicles running around the track it would be pretty boring.

Regarding support by Garrett/Honeywell: Cornell has been sponsored by Garrett for the last two years and we have been satisfied by their support. We have chosen to not run a Garrett unit both years, for a variety of reasons, but we are still in the process of testing them and might decide to run one in the future.

In my opinion, a really good turbo system in Formula SAE requires a lot of engineering behind it, and Garrett has been basically unwilling to do the engineering for us. I think this is the way it should be - FSAE is a student engineering competition and the engineering should be done by students. Our turbo system, as it exists now, is the result of years of evolutionary engineering. Example: our E-Wastegate system. It was dreamed up in 2002, outlined on paper in 2003, built and run in 2004, and improved in 2005. I suspect (hope) it will be improved even more for 2006.

So, in conclusion, I would say I don't think Garrett should make any drastic changes to its FSAE support package.

[Charlie]

I see Z. No I don't think you're ranting yet. http://fsae.com/groupee_common/emoticons/icon_wink.gif

I hadn't seen the latest article. But in my day (I sound old http://fsae.com/groupee_common/emoticons/icon_wink.gif ) I only ever saw one top 5 team have a supposed 50:50 weight distribution and we kept track of that.

I hesitate to believe anything in print. I only believe stuff from the horse's mouth. I love that mags like Race Tech support and publish articles on the series. But of the half dozen articles written about our car, they've all contained big errors, stuff way out in left field. Hell for our Race tech article I was the contact and I was interviewed, so I know exactly what went down. Somehow our car ended up with a reversed cylinder head! I don't blame the writers or editors, it's just that it's tough to get it all right.

I suspect the standard answer for weight distribution would be 50:50 if you don't know for sure, or don't want to say. After all most cars are close. I'm not saying I know that but I wouldn't be suprised if those numbers aren't completely accurate.

[Frank]

THE problem...

It is hard to make a 600 cc, with a relatively short wheelbase (nimble car) and have a significant rear weight bias. It's is much easier with a stacked gearbox.

It's easy to make rear heavy POS with 1700+mm wheelbase.

Try putting a weight near your diff (or the most practical rearward position), to shift your weight distribution back, and see what happens to the acceleration times...

[rjwoods77]

Thats the issue you sign on for if you use a 4 cylinder. There are a good number of engines that would package way better that wouldnt have a huge percentage of power loss over a turbo 4 cylinder. Case in point is our clean snomobile team. They were the first ones to throw a 4 stroke turbo engine in that competition. Started with a single cylinder polaris turbo and now they run a parallel twin honda silverwing engine with a gt12 on it. Made 80 hp reliably and kicked everyones ass for like the 3rd time in the events history. The reality is it is dirt simple and they really didnt put that much work in it and it handles good. They are running a new parallel twin this year that polaris used in there watercraft and will probably smoke everyone again. I gave them the option of using our old f4i engine and they said no because it is huge, heavy and high cg. That honda silverwing engine is like 30 degrees off horizontal. So you force yourself into packaging problems depending on what motor you use. So would you trade say 20 hp for 25 less lbs in engine weight, better rear weight bias due to packaging(if that is a goal for you), and the other accumulated weight loss due to a smaller package?

[Jersey Tom]

But rob..does it SOUND good

[Chris Davin]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Rob Woods:
Thats the issue you sign on for if you use a 4 cylinder. There are a good number of engines that would package way better that wouldnt have a huge percentage of power loss over a turbo 4 cylinder. Case in point is our clean snomobile team. They were the first ones to throw a 4 stroke turbo engine in that competition. Started with a single cylinder polaris turbo and now they run a parallel twin honda silverwing engine with a gt12 on it. Made 80 hp reliably and kicked everyones ass for like the 3rd time in the events history. The reality is it is dirt simple and they really didnt put that much work in it and it handles good. They are running a new parallel twin this year that polaris used in there watercraft and will probably smoke everyone again. I gave them the option of using our old f4i engine and they said no because it is huge, heavy and high cg. That honda silverwing engine is like 30 degrees off horizontal. So you force yourself into packaging problems depending on what motor you use. So would you trade say 20 hp for 25 less lbs in engine weight, better rear weight bias due to packaging(if that is a goal for you), and the other accumulated weight loss due to a smaller package? </div></BLOCKQUOTE>

I read through the Clean Snowmobile Challenge rules once - at the time they allowed 4-stroke engines up to 960 cc, forced induction optional, no restrictors, and E85 as a fuel option. I'd have to go with a turbocharged CBR954RR with dropped compression. Should be good for about 250 hp. :-D

[rjwoods77]

Tom,

The thing sounds real mean. The thing pulls a crazy wheely when it tears out of the hole. Team Industries/Bender clutch and a turbo 4 stroke gives this thing some pretty brutal low end pull that most snowmobiles can only dream of. This is with a moderate engagement rpm too. Snowmobile that nearly stands up because the track hooks and trys to rotate the nose. F'in sick.

Chris,

Those rules are a recipe for a mean ass engines. Only problem is the emissions and milage requirments. The engine they run is a 632cc with a turbo and they are doing well. The new engine is something Deussen nows about and should eb way better than that silverwing engine. I thought about running that engine sleeved to be legal just to cut down on development time but the one I have now I can carry with one arm so that is taking me in different direction. I am tellign you though.. the first person to run that maxsym engine or that aprillia engine is gunna be in hog heavy(if they can afford it) because of packaging vs power. Hahahah. Did I just come up with a new measure?

[Z]

Cam,

I don't want to hijack your thread, but the following is relevant to the "turbos give too much power" argument.

The following quotes are taken from a Racecar Engineering (June 2002) article on the Brabham BT55 designed by Gordon Murray. For you young'uns out there, Murray was a hugely successful F1 designer who went on to design the McLaren F1 supercar. Bernie Ecclestone is said to have found Murray "in a broom closet", when he took over Brabham.

------------(Note; my added emphasis below)---------

BRABHAM BT55
============
"Within the first few grands prix of 1985 Gordon Murray knew that the following season's Brabham needed to be a radical departure. ... The problem lay with the BMW engine. ... Cosworth's Keith Duckworth came to peer into the engine bay and said, 'Four cylinders and one turbo? It'll never bloody work,' or words to that effect. Yet BMW's Paul Rosche ... proved Duckworth wrong on the power front, eventually achieving something over 1400bhp in qualifying trim, the figure being the maximum BMW's dyno would register.
...
"But the packaging problems imposed by the tall, upright in-line four were, by 1985, taking their toll.
...
"Murray's daring solution was the low-line BT55, in which the BMW engine was canted over at 78 degrees...
...
"And so the low-line BT55 was born, a car which had all the ingredients to be a winner ... But in actuality the car performed wretchedly in 1986, ammassing just two world championship points. There were various reasons for its failure ... This was the first Brabham to have an all-carbon monocoque ... 'There were several small problems that didn't, in themselves, wreck the performance' says Murray. 'One was that, even with carbon, I don't think the torsional stiffness was ever good enough...'
...
"Much more serious were a basic traction problem... 'It had piss poor traction because I hadn't stopped to do the sums. Lowering the centre of gravity so much was wonderful for going around corners but I should have put two or three per cent more weight on the back axle. That would have been enough. A 10-year-old could have done the weight transfer calculation ...'
...
[Murray then left Brabham and moved to McLaren]
...
"Murray set about the 1988 [McLaren] car and a second low-line design... The result was the legendary MP4/4, a car that won 15 of the 16 grands prix in 1988... Is it fair to describe the MP4/4 as the BT55 done properly though? 'Absolutely,' says Murray... 'And we didn't get the weight distribution wrong!'

-----------------------------------------

So there you go, from the cellar to the penthouse with a few extra percent on the rear axle. http://fsae.com/groupee_common/emoticons/icon_smile.gif

Z

[310Turbo]

Sorry guys, I can't follow the forums as closely as I would like. Thanks for all the good comments so far.

Yes, you're right. Garrett has a very tight policy on not assisting FSAE teams with matching. We believe that this presents a very challenging problem for teams to tackle and we believe this is the essence of the competition. If we simply told you what turbo to use and how to tune it, where would the challenge be? So in that respect, we keep a hands-off approach. I think that we may need to start upping our assistance wrt to oil plumbing and pressures as it seems many teams are having oil control issues. I will have to consider this point further.

As for the carbon seal turbos - correct, some teams have received carbon seal turbos. We had attempted to get these turbos for the US competition but it became cost-ineffective. If we were to sponsor teams with carbon seal turbos, we would have to cut our sponsorship to about one-half of what it is today.

As such, we approached the FSAE committee for a rules change which would help alleviate much of the oil leakage issue teams face. No word from the committee yet so we'll see what happens next.

Thanks for the good posts so far, I hope this dialog continues and that more teams chime in. I agree with the concensus so far, that new teams with short development times should stay away from forced induction until they have a solid chassis and n/a powertrain setup.

Best regards,

Cam

[Matt Gignac]

Would there be any chance of getting these seals seperately though? I understand that shipping these units from Australia (where I understand they have the carbon seals) would be quite cost-prohibitive, but it couldn't be that bad to ship them loose? Or are they not completely swappable with the stock seal?

And I don't know how well the rules committee will take to changing the rules to help teams with oil consumption issues. I think it's been discussed before, and their conclusion was that any rule change meant to make the turbo compressor not see vacuum (thus solving most leaks) would mean the turbo before the restrictor, and the potential for too much power... would be cool though.

Cheers

Matt Gignac
McGill Racing Team

[markocosic]

Shouldn't think restrictor on the turbo outlet is something the rules committee would ever agree to, but a rule change to have restrictor on the turbo inlet and the throttle on the turbo outlet /could/ solve oiling issues without allowing silly power?

Throttle closed is no problem, throttle open and no boost is no problem. The only 'issue' is when on boost and the restrictor choked. There'd be a slight vacuum, but not the very high vacuum you get on closed throttle overrun - this would probably not be enough to draw the oil past the seals, especially if you're running a drysump that's 'vacuuming' the crankcase anyway?

Even if it were to leak a little, by definition you'd be at maximum air flowrate, so any little bit of oil that did leak past wouldn't cause the slugs of blue smoke that lots of oil at low airflorates causes.

If excessive shaft speed and high exhaust backpressure from a closed wastegate is an issue then the electronic wastegate is your answer?

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I agree with the concensus so far, that new teams with short development times should stay away from forced induction until they have a solid chassis and n/a powertrain setup. </div></BLOCKQUOTE>

I'd go with that too - turbos (and possibly smaller or lower (when nat asp) specific output engines to match) are by no means written off, they're just something to look at once you have the time to address the issues involved.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Garrett has a very tight policy on not assisting FSAE teams with matching. </div></BLOCKQUOTE>

I'm not so sure about that... ...none of the FSAE options are as way off the mark as a "GT0.12" or "GT1200" might be - the range on offer does give a few hints. http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Dave Cook]

Cam

What do you know about Honeywell's supply of the little Turbodyne electric superchargers? Cal Poly Pomona used one in 2000 and I haven't seen one since?

Dave

[310Turbo]

I won't comment much further on the proposed rules change but it was done in such a way so that turbos would not have an advantage over n/a cars, ie turbo before the restrictor.

The carbon seal itself is a costly item to purchase/manufacture. To retrofit an existing turbo means taking a built turbo apart, machining existing components (or making new ones), re-assembling, and re-balancing. The man-hours required to do these conversions is high, as are the materials. It is not a drop-in replacement.

My comment wrt matching was that we want the teams to perform the match themselves. On some teams, the student tasked with making the match must show to the rest of the team why one turbo works better than the other for their application. Our limited offerings (GT12/GT15V) are a pretty big hint http://fsae.com/groupee_common/emoticons/icon_smile.gif

Dave - I received your email regarding the Turbodyne and forwarded it onto a colleague. I will double back with him and ask him to respond. Is there a specific question that you want answered?

Best regards,

Cam

[Dave Cook]

Cam

I was just wondering what happened to the superchargers, it looks like Turbodyne went under and I'd hate to see those units get melted down for scrap when they were a good size for the restricted FSAE engines.

Please send me a contact email when you get it, you can also leave it as a private message.

Dave

[310Turbo]

Dave - what I could gather was that the company went under. I don't know what happened to their stock, I'm doubtful that any are left.

Sorry I couldn't be of any more assistance!

Cam

[UQ Turbo]

G'day All

I'm throwing around ideas for the compressor outlet to intercooler inlet air tract and have come up with with an issue. The GT12 workshop drawing suggests a 7 degree diffuser at the compressor outlet (taken to twice the area)for 'best performance'. This means that a 30mm ID outlet goes to a 42mm or so ID. This is all good, but popular opinion in the performance scene (at least in Queensland, Australia) is that intercooler pipework should have air velocities up around 70 m/s to reduce lag. The big 42 ID pipework is used sucessfully in rex's and Silvias! I'm just curious if anyone has experimented with diffuser/no diffuser setups and seen any difference.

One thought is that the diffuser is recommended for non-intercooled applications and that the pressure drop due to any sudden expansion into an intercooler end-tank will be dwarfed by that of flow through the intercooler core anyway.

I apologise for any lack of clarity there... Anyway, if anyone has thoughts that would be appreciated!

Cheers,
Michael
UQ Turbo