Here is the math
mph= (rpm x tireD x pi)/(1056x R1R2)
say 58mph =(3600rpmx26xpi)(1056x 1.0Top gear x R2 the diff gear.
Rearranging for R2 we get 1/R2 = (58x1056x1)/(3600x81.7) and then
1/R2=.20824 and finally; R2=4.80 rear gear
Now 4.80 is so far from 3.55 (35%),that one would have to conclude that something is outta whack. And really there is/are only three things it can be; 1) the speedO unit, or 2) the TC is slipping fiercely, or 3) some combination of the two.
As a comparison,my 4-speed car was set up with 3.55s and 26s, way back in '99. And the same formula spits out 2570@56mph, (or 2754rpm at 60mph). And my tach was reading about 2600@56 which is a 1% disagreement.
The math is good.
Since you calibrated your speedO with another car,If I had to guess,I'd guess your TC is slipping big-time
Well there is one other possibility, and that is a failed tranny. But you would have mentioned something about slipping gears.
So at this point, I would be proving that the assumed-to-be 3.55s really are 3.55s,lol.If they are,then I would be calibrating the tach. And if it is good, then I would be pulling that TC.
It may be a little early to be shopping for an O/D[/QUOTE
I think your math or memory is wrong, my trans isn't slipping nor is my converter, this is not my first hotrod, as I said my numbers may be off but not by much but who really gives a **** anyhow? As stated above the rpms are over 3k somewhere and it is very uncomfortable at cruising speed, does the stupid math about rpms vs mph make any different other than you trying to be a wise ***? This is a forum for enthusiast to share opinions and knowledge to a certain extent, this isn't lets see how smart we are how how big our dicks are.