Thanks Scott, but I don't know what the gears are in a 700r4, I quess I asked the question wrong. "RPM for speed in gear" is the chart I need, but I don't know what to put in for transmission gear ratio. I'm hoping someone knows the ratio of each gear in the 700r4. I should ask Chris at CKPerformance he is definately the trans expert here!
Thanks for the calculator site Scott.
Right now all I do is spin tires in first gear, was hoping posi would help some there. When it shifts to second it kind of bogs a bit, maybe the drastic change of gears from first to second in the 700r4, 3.06 to 1.63, anyway was hoping lower rear gears would help. 3.08's now. I quess I'm looking for the best of both worlds, I want to jump off the line fast and cruise 75 down the highway comfortably, you know the deal, with the A/C on and everything.
I know what you mean. I think with the posi and 3.55's you'll be good to go.
Once I'm done with my frame off, I'm going to drop my ratio down from 4.56 to 4.11's so I can actually hit the Highway's. Right now 75 is 4100rpm, with the 4.11's it will be about 3600rpm. 65 will be at 3200rpm which is where my cam comes in and the motor smooths out.
just remember that when it's time to get the speedo all calibrated, use the rpm in third gear to find your final drive ratio. if you use the 4th gear ratio, your speedo will read 30% slow. or is that 30% fast? well, it will be off 30%..
say you end up with a final drive ratio that gives you 2800 rpm at 60 in third gear- that would only be 1960 rpm in overdrive.
if you base the speedo calibration on the 1960 rpm at 60 mph- 1.96:1 final drive ratio- then your speedo will be way off. but if you base it on the 2800- or 2.8:1 final drive ratio- then the speedo will be right on.
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