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Old 09-04-2003, 09:53 PM
Gerry A. Gerry A. is offline
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Join Date: Jul 2003
Location: Rolla, Missouri,
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Now I'm somewhat confused, I went to the site you recommended Clois and here's what I discovered. If I go with 3.89's I'll be running freeway speed (right around 70) at just a touch under 2500, it worked up to 73mph at 2500. If I go with the 4.11's I'll be running the same speed at approx. 2700 or so really not much difference. I did discover something very interesting however.. I did the calculations assuming I did not know the rear end ratio I had and going by the RPM vs. speed to give me my final ratio it showed something I wasn't expecting. I know by observation that I run 60 on the speedo at 2000 RPM showing on the tack in 4th.. I've done it a hundred times so common sense would say that if in fact 4th is 1:1, which it is, my rear end ration should be 3.00. 2x3=6, or so I thought.. maybe it has something to do with the tire dia. which it also asked for because it said that my rear end ratio was 2.563:1. Did I do something wrong? When I was doing the math awhile ago trying to figure things out I kept comming up about 9 mph different than it should have been mathematically and you know what?
When I plugged in 51mph instead of 60 and used 2000 rpm as the reference it said my rear end ration was 3.015...now is that coincidence or what? 9mph difference and the ratio comes up so close to 3.0 it isn't funny yet logic would tell you that at 60 if 2000rpm is showing on the tach then the ratio should be 3.0. This is getting silly. More and more I'm thinking I should just leave things alone but I can't help but feel that 3.0 is a bit tall when it comes to performance even if I do lose a small bit of drivability.. according to the charts I won't lose that much either way I go 3.89 or 4.11 but I'm leaning toward the lower one just to be on the safe side. besides the 4.11's are almost 100.00 more. Guess it's because they are more popular. What is the census poll on this one? Thanks for the site though I think it provides alot of good info in lots of areas.. I have it in my favorites now and will use it from time to time.