OK, so after waiting for the parts to be delivered across the pond to me here in the uk, I finally fitted a TCI Streetfighter tc which is 1500 rpm over stock; a Richmond 3.73 rear end in place of the stock 2.73. I used Hypertech 111 to reprogram the gear ratio and to use the power program for higher octane fuel (non rfg) I haven't played with shift points, firmness or tyre sizes.

60ft times were "slightly" better than before but et was down by 2/10th's at a slower mph. Best I could manage all day was a 13.67. Traction is still an issue but didn't seem much worse than before.

With the exception of the tc and rear end the car is the same as before so why would it be slower; the traction was still off but not significantly more so than usual. I wasn't expecting great improvements but some would have been nice

Its a 1999 Z28 auto.

 

I think you are running thru the gears too fast now...

I'd increase the shift points. I think you should run high 12's right now.

 

How similar were the weather conditions?

Weather can play a huge roll in how well the car runs.

 

what was the weather like? Like they said above weather can affect ET's by 2-5tenths!!

also i wouldnt run that HPP3 tuning for the gas and etc.. lots of guys L O O S E power with that tuning from it. Just use it for the shift points and other things but try her without that tuning. Ive seen people gain 10 or more HP by takin out the tuning on the dyno.

 

I'll try moving the shift points up this week at the track; it does seem to be going through the gears fast, crossing the line at about 6000rpm in 3rd it feels like its about to change down into 4th.

Weather was ok, about 18c, track was dry and in good condition after the easter nationals. There was a strong headwind though, about 15-20 mph which will affect the run.

Let you know how we get on after the next test day.