Toxcheap

Explain why the others used v8's are you saying those were 3.0L's too.

shortyq

The Mercury v8 and v6 ran in the same GTO class. Get some books on IMSA GTO and Trans Am series. Three things are becoming obvious: 1) this is transgressing from the I5 development topic 2) You are not clear on any type of homogolation or equivelency rules in racing and 3) You are avoiding backing up your claim that you "spoke" with anyone regarding I5 development.

Drop it?

Thanks

Scott Justusson

cuatrokoop

definition, why would the 90q20vt car be limited to 2190cc and the multiplier of 1.4-ish for an equiv. displacement of 3.07L? That to me doesn't make sense, and is why I brought the Cougar up. I can't find the old regulations (only the '04-05 stuff), so I can't answer my own question.

The really screwy thing is that they ran the V6 (flat hood) and V8 (cowl hood) at the same events.

The #6 Cougar was running a "2500cc Turbo" at Summit Point. The #4 & 5 90q20vt's were running a "2100cc Turbo". At Mid Ohio, the Camaro was running a "5500cc" V8 in GTO, the #6 and #9 Cougars the same turbo motor. The #76 300ZXt was also running a "2500cc Turbo". Using the same 1.4 multiplier, that puts the Nissan and Mercurys well north of 3.0L, and the Camaro with its V8 is definately north of 3.0L.

shortyq

In 1989, GTO by definition, stands for Grand Touring "Over" 3 liters. Just about every turbo car in GTO was bumped by equivelency (reread the posts - only group 4/B FIA ran 2.1 to stay *under* 3.0L equivelency)to be over 3liters. GTO was 3.0-6.0 liters (including equivelency cars) in 1989. Trans Am was limited to 510hp, GTO was limited to 620 and worked it's way up to 720 by the end of the season.

All that said, the engine lines had to be based on production motors. Audi could meet the HP limits (and beyond) of both Trans Am and GTO with the same bore and stroke motor. The bottom end was race proven, met Homogolation rules, and was bulletproof.

Audisport could have 'extended' their welcome (cough) in GTO with the v8, but decided instead to enter it in DTM racing in Europe. Audisports brief foray into the US circuit caused quite a controversy, and the crossover to car sales in US isn't as strong as in Europe.

Follow the thread carefully above. 2.1 in Group 4/B WRC used 1.4equivelency base to keep the quattros in the 'under 3 liter class'. SCCA and IMSA used a higher equivelency to bump the cars into the 'over' class. All series had many engine restrictions, which audi could meet with the same bore and stroke that kept them in Group B. Why change something that can satisfy all rules?

More trivia, IMSA GTO required that Audi disable the 6th gear in the 6speed gearbox (forward gears limited to 5).

Hope this helps clear up the mud.

Scott Justusson
QSHIPQ Performance Tuning

Toxcheap

Hope this clears the mud LOL you never answer a question! Double talk and technobabble at best.

Hope this clears the mud.

PS Missed you at waterfest :0P

captaudi

Toxcheap, you are making this a personal battle instead of a meeting of the minds reagrding I5 development and history. Audi used the 2110cc motor in the IMSA series for 3 main reasons. First they had it, and it was a strong proven performer. Second, IMSA rules stated the engine/chassis combo had to be based upon a production vehicle. Third there is/was a cap on engine output and Audi had an engine that met all 3 criteria. Remember that GTO stands for Gran Turismo Omologato. Or Homologated for Grand Touring. This meant that all aspects of the IMSA car had to meet that criteria. If yoy have other info than what is clearly documented by both IMSA/FIA and Audisport bring it on. Just make sure you can provide solid evidance to substantiate it.

Cheers,

captaudi

Toxcheap

I also have no problem respecting peoples requests not to be brought up in these childess threads. I only try to share with other what I learned, and if I heard that it's best to leave that cylinder thickness alone because of how great the cylinder pressures become in high HP applications would you rather I just not mention it, would that be more a meeting of the mind by your definition? I figure it like this, hasn't done me to wrong yet. Ask 2.6urs4 if he's still on his first motor.

cuatrokoop

"Follow the thread carefully above." Tried that, didn't work, asked for clarification ;-)

shortyq

Toxcheap:
It's not disagreement as much as it is misunderstanding. It's quite clear to me that only a few really have delved into IMSA and Trans Am Audisport efforts. Cuatrokoop was closest with the v6 and the v8 Mercury's running in the same class. Some tracks worked better for the v6, some for the v8 cars. Why?

I have a long history of correcting Audisport misunderstandings, many of them belong to you. GTO and IMSA and Group B are so well documented, you have had to contradict your own posts (first oversquare, then cyl wall thickness?). I'm quite comfortable regurgitating my dusty library, and am also fascinated by any deviations from it. IF they are valid.

When I can't pull that exact information from a guy that 'claims' to have it, 'disagreement' would be the nicest word I can think of calling it.

Peace

Scott Justusson

shortyq

Koop, if you want more on Mercury efforts, email me privately