My car runs 12.39 at 110Mph on 1.83 60' times. This on Eagle F1s (275/40/17).

The car has the mods at the bottom of the page but am thinking it was not tuned correctly. The car shifts from 1st gear at 5,500 RPM (224/224/563 Thunder Racing Cam) but should be shifting at 6,500RPM. 2nd gear is shifting at 6,200 RPM. and should be at 6,500RPM. when I put the car on the dyno it put down 405RWHP and 379RWTQ.

The Other issue was the AF Ratio is 12.0 all the way through the entire run.

So, can someone tell me how much better the car would run (Estimate) bumping the shift points to 6500RPM and adjusting AF ration to 13.0?

I figure I am missing like 1,400 Rpm of pure power because of shifting out to early.

I would just like some opinions on this.

Thanks for the input.

Bill

 

There's two issues here. Gaining hp and using the hp you already have.

First off, the 12.0 AFR is actually about where you want it up to your peak torque. Beyond that, you can lean it out down to 13.0 as you approach peak hp and then richen it back up to a 12.7 or so after peak hp. That may get you another 5hp or so, but don't expect much.

Second, don't forget the stock tach pretty much sucks. In first, it looks like my car shifts 2-400rpms sooner than what it really does according to EFILive. So, you're most likely shifting closer to 6,000. 2nd gear isn't as bad as 1st, but there is still some delay. Optimizing your shift points may get you at most another .05-.10 seconds off your best time.

That's just my opinion. So, take it for what it's worth...

 

If it shifted at 6200 you'd see a small gain in 1/4 time, the a/f isn't to bad but there may be a small gain to be had there as well. Get a good tune and see what happens!

 

Weight ... between your wheels, the Corsa and your sound system ... your car is nice, but as far as striaght line racing, it's a pig.

405rwhp should be mid 11s ...

 

How much weight do you think I need to drop to make a big difference?

I was thinking of going to some drag rims with skinnies up from.

Just not sure where to start?

Thanks,

Bill

 

Skinnies are good place to start. If you still have your stock wheels, put a set of ET street on them for the rear ... better yet a set of 15" drag wheels on the rear.

Dump the Corsa ... just about anything other than the stock muffler will be lighter ... but stay away from a Flowmaster - to restrictive at your HP levels.

Strip some weight out of the engine bay ... window washer bottle, light weight battery.

Race day weight reduction ... passenger seat, back seats and front sway bar ... total about an hour of work.

And last ... how much does that Alpine system weigh?

As far as difference ... compare your 405 rwhp A4 to my 403 rwhp A4 in sig ...

 

Thanks for the advice. Can you tell me what kind of converter you are running? I am thinking this is part of my problem. 2800 with 3:23 gears.
Thanks,

Bill

 

A custom TCS 3800, 2.85 STR, with a 5500 rpm shift extension.

Your 2800 Vig isn't that bad ... I've seen more than a few folks hit 11s with them with less hp than you are putting down. I was running 11.8s with a Yank 3000.