Many of you that know as from e-town know that we converted my Dad's LT4 corvette to an A4 using stock components from a 1996 LT1.

We have been testing the car over the past few weeks at Raceway Park, Englishtown, NJ and the results have been remarkable despite the hot weather. We are running et's consistently in 12.6's to 12.7's and in the cooler weather last wednesday went a 12.48.

Other mods include a GM hot cam, 4:10 gears, BFG 315 DR's and a heavy duty radiator with a 160 thermo. Most everything else on the car is stock including the stock exhaust manifolds (it does have Borla mufflers though).

We converted the car primarily because we use it as a drag car, and unfortunately my Dad had a helluva a time driving the 6M consistently (he's not the only one). Plus I got tired of changing worn out clutches every three months ;) .

So if consistentcy was the goal, then the car has far exceeded our expectations. Check out the data below. My Dad took 2nd place in the GM Hi Tech performance race in the AM session on July 14th. He handed the keys to me for the PM session of the Cartek Corvette Challenge, were I lost to REDGAR in the semi's. As John Mackey says, converting to an A4 was "the best thing you could ever do!"

The most amazing thing has been the improvement in the 60' time. With the 6M, an average day would yeild 60' that were anywhere from 1.85 to 2.00. We considered a 1.80 to be VERY good. The A4 rarely has a 60' greater than 1.80.

We will be looking for very low 12's once the weather turns cool. And who knows, maybe next we'll port the heads!



Note: bold entries in the table above are new personal records.

 

:cool: :cheers: :cool:

 

The car is deffinatly hooking better. I saw your Dad when we got there and he said he was still running in the GM race, I said I guess he was happy with the conversion. :D

 

Kinda sucks that GM didn't build the LT4/A4 combo.
What kind of converter??

 

The converter is a Precision Industries Vigilante, 3000 stall.

Also some people have asked for some "before" data.

Here's some data from last year. The car was in the same configuration except with the 6M and with a single mass flywheel. I picked a day that had similar weather conditions to this past Saturday.




[Modified by Eric Fischer, 2:04 PM 7/16/2002]

 

im glad you posted this. my friends all ask why i own an automatic.....they dont believe an automatic is faster. you just proved them wrong! :yesnod: :cheers:

 

Now that you have an A4 in it, do you think you'll change out the 4:10's to 3:73's? How is the auto with 4:10's?

 

The auto is not faster, just more *consistant* with a driver who isn't good at paddling gears.

 

so why are most drag cars auto's? :confused:

 

As long as the car has traction with the 4.10's, there is really no need to go down to 3.73's. However for a daily driver, I think the 4.10's are a bit much for highway driving. If the car was to be driven everyday, we'd probably go down to the 3.73's or maybe even the stock 3.54's.

 

I think the A4 will wind up being faster be a slim margin. With the A4 you gain quite a bit in the 60', but because it's not as efficient as the 6M, you lose some at the big end.

I think the car on average will be consistently faster too - i.e. as long as the track cooperates the car will routinely run 12.4's to 12.7's depending on the weather.

The A4 just launches harder and more consistently than a 6M (at least on drag radials). The 6M can be made to be consistent (big tires or slicks, rev limiter for launch, etc), but you still run the risk of missing a shift. Somedays, with the 6M I could launch as high as 5000 RPM without wheelspin. Other days it would spin at 3000 RPM and I would have to slip the clutch to get a decent launch...

 

Adding an A4 would probably hurt resale. I like the gears

 

Eric, excellent results. This fall/winter I'll be going the LT4 conversion/HotCam route with my LT1. I'm having the tranny gone through also and your specs have me feeling better about an LT4/A4 combo.

 

:cool:

 

Agreed. That's why I installed it in a manner that it could be easily undone and put back to stock.

 

It's all about control to me. I'd much rather shift my standard than have the little imaginary guy inside my automatic do it for me. If you're looking for *Consistancy*, then I think an automatic is for you. As for me, I love to know I can run each and every gear in my box out to 15,000 RPM if I wanted to, if only the car would stay together. I'll risk missing a shift, and having to swap clutches. For straight lines... automatics are less work, road racing...fuggedabout it. But I guess it's like a Chevy / Ford discussion...... Eric, congrats on your times, very good looking to me! I'm glad you're getting the numbers you were looking for, and then some! I'm off to hit the limiter, drop the clutch, and leave this discussion! :seeya

 

I agree with the "control" issue. However, after 6 years of shifting a Camaro, I took the lazy route with my vette. Now, as for performance...that little "imaginary guy" can shift my auto faster than you guys can shift your 6 speeds. And besides, he works cheaply, never takes breaks and doesn't eat much! :D :D

 

:cool:

 

:yesnod: Hey Aqua, how about you and me play with our little toys around town some day. I know you out mod me, but can you out drive me? :boxing

 

Interesting results. You lost a couple of mph, but picked up a couple of tenths due to a better 60' time. :cheers: