That could be your problem right there.....you didn't change the cam or anything so your HP hasn't shifted that much really so you aren't peaking up that high. The point is to shift right around peak HP which is down around 5200 or so. It also doesn't help that it was humid.

 

I'm in the same boat as you (times and mods in the sig) but I could only shift at 5800 since i have a rev limiter there and I pulled my best times there, of course, I do have a cam which moved my powerband up some. I'm sure if i could ahve shifted @ 6-6200 i could have pulled some 13 second times (probably if i just learned how to launch the damn thing) and some 101-102 traps. AFAIK, most people with stock LT1's shift @ around 5500 to get the best times.

 

stock limiter is at 5,800 rpm's so the tach is probably off

 

But he got a reprogram so that could have been changed. Either way, even 5800 is too high

 

ok thanks i will try shifting at 5200 next time that chris

 

5200 is too low. The automatics shift right at 5700 (although my tach is off and reads 6000 on the shifts) and they run quick ETs this way. I tried lowering my shift points on another LT1 I owned and it ran slower ETs that way. 5700 is perfect for a stock LT1.

You never want to shift right at peak horsepower, you want to shift a bit higher. If you shift at the peak, you'll drop too far down in rpms to make good power. Your best bet is to rev it over the power peak that way you keep the engine in the area with the most average horsepower. If your peak is 5200 and you shift at 5200, it'll drop you down to probably 3500rpm in the next gear, which won't give you as much power as if you shifted at 5700 and the rpms only dropped to 4000 in the next gear.

 

Yea thats why I said around peak HP not AT peak HP. I shifted around 5500 before my cam work and everything and I was trapping 102 and change