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 mad2002tii |
Turbo for DSR |
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Registered User
Posts: 501 06/25/08 17:26:29 |
So after the amount of calls that I have had on this subject and me not being a motor guy I thought that I would throw this out on the forum.
What are the anticipated performance numbers for a 670cc turbo, cost, and reliability? Any takers?
Mike Devins
hrp-llc at comcast dot net |
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fastercar |
#1 | |||
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Registered User
Posts: 141 06/25/08 17:37:00 |
Mike, I was looking into this this past winter and spring. My sources said I could get 250HP relabile ??? and possibly 300HP with some work. I was looking
at starting with a 1000cc block and sleeving and stroking it. Cost was ????????
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ted arken |
#2 | |||
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Registered User
Posts: 2684 06/25/08 18:34:26 |
How much money do you have for the project? If you don't have at least 15K to throw at the project, and a very interested (I.E. cheap) engine builder,
just stick with the NA motors.
200+ has already been achieved with the old 600 cc rule, so with the new one you should be able to get about 225 at the wheels with "fairly" good reliability, and more if you're willing to change motors mo frequently. I'm sure the builder will chime in here shortly, unless he is working on a new version currently...
Last Edited By: ted arken 06/25/08 20:41:09.
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Hasty Horn |
#3 | |||
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Registered User
Posts: 1191 06/25/08 20:26:25 |
The decision to sleeve the GSXR 750 was a pretty good one....trying to sleeve a 1000cc engine down becomes further complicated by need to "match the
head". In other words the piston area (diameter) has to stay in a reasonable relationship to the valve area. Trying to change the stroke will help but a
large enough stroke change will require a. different length rods and b. a different height block. Making an engine larger is usually easier than making it
significantly smaller. The GSXR 750 has a pretty strong lower end and tranny so it would be a good candidate.
If I could choose from any of the manufacturers for this activity I would start with the Triumph 675cc triple. I may be proven wrong in the long run but I think that turbocharging using motorcycle donor engines for D Sport domination will prove expensive and ultimately too prone to failure. On the other hand (since someone else is footing the development bill) I find it wonderful that someone has the guts to go down that path. Hasty Horn |
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mad2002tii |
#4 | |||
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Registered User
Posts: 502 06/25/08 21:12:39 |
Hasty, do you think that the trans will be able to handle the load?
Mike Devins
hrp-llc at comcast dot net |
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Juan Montalvo |
Limits | #5 | ||
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Registered User
Posts: 50 06/25/08 21:49:18 |
Rephrasing the question: Assuming all obstacles are worked out-fuel delivery, cooling, crank,tranny, clutch, case flex, etc. just what can a 670 turbo reliably
do? Full race distance, not just a dyno pull.
Last Edited By: Juan Montalvo 06/25/08 21:52:50.
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Hasty Horn |
#6 | |||
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Registered User
Posts: 1192 06/25/08 22:09:59 |
Tough question because I have been very surprised that the 1000cc units haven't seemed to suffer from the abuse that we heap on them. Not so much in the
"forward direction" but the backward resistance direction. The weight of a two passenger motorcycle driven hard isn't far off our typical weight
but the traction and spinning load of two rear wheels is much higher. Still, my guess is that rods, and rod bearing failures first, second valves and head
leakage and lastly clutches and trannies. I'm not totally familiar with the GSXR-750 but if memory serves the 1000cc engine and the 750 may share
transmission components or, hell, it may be the opposite that the 600cc shares with the 750cc.
Since we all remember the 1000HP (or more, the number ranges up to 1200 HP), 1500cc turbocharged Formula 1 engines it is possible to build an engine that will survive. That's starting with a clean sheet for an engine design. Trying to stay within the parameters of the original motorcycle design is much harder. When the manufacturers made turbo bikes (early 80's?), they didn't run anywhere near the boost pressures that are being tried today. The turbocharged Yamaha XJ-650 was rated at 90 HP (@9,000 rpm) and was an air-cooled engine so that might be comparing apples and oranges. I actually thought that the use of turbo-charged automotive engines (four years ago at Mid-Ohio?) based on the micro car engines out of the Far East stood a better chance of success but I guess we'll see. Hasty Horn |
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ted arken |
#7 | |||
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Registered User
Posts: 2686 06/26/08 00:37:26 |
I would guess around 275 Juan, with at least some amount of reliability. But it won't be cheap.
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Dick Boggs |
#8 | |||
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Registered User
Posts: 49 06/26/08 12:48:42 |
George has been waiting patiently for someone to come forward that wants to do it. We stared out with a turbo ZX-11 with about 245 reliable RWHP and then
developed a Suzuki turbo 600 with about 220. This was in 2001-2003. I decided I wasn't getting enough seat time and getting ready to retire and it
wasn't doing George any good either. We went through 7 motors, developed our own dry sump system, injection system, etc. for the motor. Ted come up and
got to drive it. He needs to tell you what it was like to drive. Very smooth power.
Lot of inter change between Suzuki parts that we used. Never a problem with transmissions, clutches or dry sump oiling/cooling sytems. Need to talk to George if need more details. All it takes is your money |
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Lee Stohr |
Turbo | #9 | ||
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Registered User
Posts: 939 06/26/08 12:49:16 |
Imagine a DSR faster than a LeMans Audi ! 950lb at 275hp equals 3.4 lbs/hp. Audi R8 turbo gasoline engined-car was 2025lb at 550hp equals 3.6lbs/hp.
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ken kaplowitz |
turbo power | #10 | ||
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Registered User
Posts: 497 06/26/08 15:24:18 |
why 4 stroke? Back in the late 80's Finger ran a 2 stroke turbo that had gobs of hp but would blow the crank seals.This problem has been cured by the
snowmobile guys.So Mike ,jason orJeff get on the stick and put tears in all their eyes.
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KMA4444 |
#11 | |||
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Registered User
Posts: 322 06/26/08 16:21:26 |
I would agree that 300 is attainable without any real drama. The biggest problem is, as has been stated, the bike engine architecture. I don't think the
required cylinder pressures will be easy to contain, my biggest concern will be the seats moving in the head. Drag bike guys playing with nitrous have run into
problems with this.
One of the problems we had with our engine this year was poor valve sealing, you could see light around most of the seats when you held the head up to light. It was a used crash bike engine and there was no obvious damage to pistons/valves and the valves turned true. I had to cut all the seats to get the valves to seal. One theory I heard was that while the bike was being turned into a donor for our car, the operator winged the mess out of it. I don't have a better idea as to how it could have happened, but I know we had a problem with the seats having moved or distorted. I'm pretty sure the GSXR 750 is based more on the 600 platform. It is certainly a 600 sized engine from the outside, of course the bike is 600 sized too, with almost litre bike power, neat piece.
MallenAlley.com
Kevin Allen |
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LDOGGYDIZZLE |
turbo | #12 | ||
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Registered User
Posts: 31 06/30/08 15:18:46 |
Ive been posting some stuff in the Sprints discussion about turbo DSR's and today I found this page. So below are some of my points copied and pasted form
other page:
I too have always theoretically calculated hp for a turbo package with a 670cc. Ive been playing with turbos for years on Mitsubishi's. Currently my EVO, with the stock 2.0L, aftermarket cams, GT3076 turbo, 30psi, makes 500 whp on 110 leaded fuel. With a built 670cc w/ proper supporting internal components, engine managment, I/C...... 300hp should be EZ IMHO. I've always thought about it, but now seeing the champ tinker with it, he's really pushing me to try it!  But for now, im happy enough to have a chassis on
order, I guess we'll see, winter is long here in WI.
Ive thought more and more about this turbo thing. IMHO, the CRB really needs to give it some thought too. I believe this package will be MUCH faster and more powerful than a the current built 1000cc packages being used. Im afraid that a lot of cars and car owners will be left in the wake. Yes, WF1's with top of the line fully prepped engines will not be competative. This could really hurt participation in DSR. But what Im really worried about is putting the time, money and effort into developing such a package and then the rules would get changed. Thats one of the reasons why I left Production. Dont get me wrong, going faster than 2:00 at RA has always been a goal of mine.
Lee, sounds cool, but a LMP1 Audi laps RA at less than 1:48! WOW 2007 Generac 500
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Lee Stohr |
Turbo 670cc Sports Racer | #13 | ||
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Registered User
Posts: 940 06/30/08 18:32:58 |
It would be really cool, wouldn't it !
I don't think you could call it a DSR anymore, especially if it becomes the fastest sports racing car in the world. However, to do that, I think you are really talking about a whole new chassis, bigger rear tires, strengthened drivetrain, increased provision for cooling, and increased downforce. Probably a wider car, which will make getting weight down even more expensive. Who knows if a bike engine-based turbo will even work at this displacement. By the time you're done, you might find it would have been cheaper to buy a 990cc MotoGP engine. |
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LDOGGYDIZZLE |
turbo | #14 | ||
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Registered User
Posts: 32 07/01/08 14:57:28 |
Yes, it definatly would be cool!
I dont think it would be that costly. Built 670 or built 1000, pretty much a wash. Then a turbo of course and a proper engine managment system, waste gate and a blow off valve or two. Add some custom goodies like a I/C and piping, intake manifold with a plenum, exhaust manifold, and down pipe/exhaust. Bingo, turbo DSR. 
And with that much power, you could run all the downforce you'd want. Gotta do something to hide all that power! Lee, wider, bigger, more tire............. Maybe its time Stohr goes LMP racin?
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mjaremko |
Turbo expense | #15 | ||
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Registered User
Posts: 27 07/01/08 18:08:58 |
Lawrence,
I think what Lee was trying to point out along with the "cool factor" was the added expense the turbo's will add to our budgets, not only for the engine and its development but chassis upgrades as well. for instance: To add a turbo package to my 2nd gen Stohr DSR would be a big expense. My engine builder informend me that to do it correctly would cost approximatly $20-25k and lots of free labour to achieve that, the engine would need rebuilds 3 times more often than my current N/A package. Then there are the chassis upgrades, stronger diff, stronger rear spar. wider wheels and tires and the floor and body work to cover them just to mention a few, and all these upgrades carry a large $ amount. IMHO if the turbo thing gets started in DSR the front runners and anyone else who wants to be competitive will all be building or buying new cars. ( maybe its not a bad idea for my friend Lee ) If our engine programs are the same $'s as CSR it will give SCCA one more reason to consolidate the class's, something many of the people on this forum are against. It will also take one of DSR's big selling points away from new people looking at joining our class, sub $10k fully modified engines and transmissions. mj
Last Edited By: mjaremko 07/01/08 21:12:38.
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GonMad SPBG |
#16 | |||
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Registered User
Posts: 429 07/01/08 21:38:04 |
Having worked on a turbocharged, motorcycle-engined road racer for several years now. I really don't think that you have as much to worry about in DSR as
you think. While the horsepower can be intoxicating, it isn't the whole story when you're talking about road racing. It is far more difficult to
balance a car on the edge of adhesion through a fast corner with a turbo, as they tend to develop torque rather quickly with throttle application, especially
when you consider that turbo cars tend to have bigger rear tires, exagerrating the front to rear balance. Have you ever read how difficult it is to drive a
Porsche 935 really fast? And while I would argue that turbo lag isn't the issue it used to be, it is still true that when you first step on the gas after
braking there is still a moment or so while the ECU tries to decide how much fuel you need as the turbo is spooling up.
Plus the not so minor detail that all of the horsepower in the world won't make up for a driver that knows his vehicle and can consistently late brake and throw it into a corner at 99% of the maximum velocity. So given the choice between say Mark Jaremko in the "classic" 1000cc DSR and Rudy Deeppockets in his 300 HP turbo DSR, my money will be on Mark! Marty
Marty Bose - #1 Gopher, GonMad Racing
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Duane Dyckman |
Money, huh? | #17 | ||
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Registered User
Posts: 322 07/01/08 22:20:13 |
Mark,
I think that's called chutzpa. What do you think the WF1 is all about? What you are saying is it will cost YOU more money. For most people on this board
the WF1 is already too expensive for a club class. JR will spend y'all into oblivion. I would have loved to have been a fly on the wall of a lot of the D
drivers when they read the turbo thread.
I can't really believe you think engine cost would enter into any consolidation discussion. The lap times and aero rules being identical have a whole
lot more to do with it. Consolidation WILL happen with the current rules structure, chassis and aero - not engine. The Sprints just added more impetus
as I'm sure the Runoffs will as well
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mjaremko |
Dude | #18 | ||
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Registered User
Posts: 29 07/01/08 23:33:39 |
Duane, if you remember back to 2001 DSR was on its lips, the Stohr DSR came along and yes, it made the class more expensive at the front and I realize I WAS
part of Lee's effort, but even though the chassis costs escalated the engines were still relatively inexpensive and in my opinion that helped attract
people to the class.
The whole reason for my earlier post which may not have been clear was that I think its bad for the class and its future. mj |
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Matthew DiRenzo |
Well... | #19 | ||
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Registered User
Posts: 34 07/02/08 00:23:30 |
None of this is surprising... the budgets were manageable 2001-2004 but quickly escalated by 2005. If you recall, Hoover had a 3-cylinder turbo engine going by
that time. I believe George had done at least 1 turbo engine. The die has already been cast; if the 670cc turbo motor will last even 5 laps at 20 psi, you now
need one as a qualifying engine to have any shot at the Runoffs pole. Driver adjustable boost / maps could result in 2-3 race laps at 20 psi before dropping to
a more reliable level. Next will be a bespoke engine block connected to a proper transaxle; again, ground that has already been covered. Turbo lag? Seriously?
DSR has fewer rules than F1. You can solve any problem. This sort of thing would happen more often if budget and skill coincided. Still waiting for a carbon
tub, brakes, etc. It's fun to watch when someone does it well.
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Lee Stohr |
turbo | #20 | ||
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Registered User
Posts: 941 07/02/08 00:39:55 |
Here is what will probably happen, if someone turns some good laps with a turbo in DSR at the Runoffs, next year SCCA will move to equalize the turbo vs atmo
engines with inlet restrictors and/or weight. So this year is likely the only opportunity to take advantage of the rules as they are now written. It's a
big gamble, but it sure makes DSR exciting !
Duane, I don't know why Lee would build a new car anyway.
Last Edited By: Lee Stohr 07/02/08 00:47:22.
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