OK, this topic is back. I put this same question up about a month ago, and the consensus then was that my lock-up on my torque converter was not working. Well, I did that little test where you get at about 55 MPH or so, and tap the brake while still on the gas. The lock-up does work, so now what?

In case you're not familiar with my dilema. . . I have a freshly rebuilt 700R4 tranny w/ a vette servo and a Trans-go shift kit, 2.73 peg leg, with 8* advanced timing. I can't recall my exact tire size, but after doing the all the calculations known to man, I should not be sitting on 2,400 RPMs at 80 MPH.

Would bumping up the timing really have THAT much of an effect on my cruising RPMs? I need some help here yall.

-The Gunny

 

No. The ignition timing has no effect whatsoever on your driveline ratio.

What's the actual problem? What do you need help with?

 

It sounds about right to me My GTA had 2.73 gears and @72mph I was at 2000RPM's...

 

ROFLMAO if you're worried about a couple hundred RPMs or a couple mph of accuracy in stock guages. You do realize it's nothing for a stock tach to be off by 500rpms or so, right?

If you want to truly know your engine and vehicle speed, use a scan tool. The computer will 1000% know exactly engine RPMs and if you're talking about the 91 in your sig, it will know your speed too because it gets the VSS signal right from the tranny, which will also be 100% accurate (for the speedo gears it has anyway, which can have error in itself)

 

According to calc you should be doing about 2000. I have attached a link to a neat calc program for rpm for any one interested.

http://www.700r4.com/SpeedOCalc/?calc=1

 

cool website, i am about in the 2 K range around 80!! my car runs fine

 

whats the test about tapping the break at 55mph while still on the gas?