Mitchell Over Drive 26% or 36%

wmws: your 3.78 rpm to mph is very correct. I do believe though that your 26% OD rpm vs speeds are incorrect. The ratio at 1.26 OD makes the equivalent of a 3.00 rear end ratio. 1000 rpm = 28.6 1500 = 43
1750 50 2000= 57.3 mph

I hope I am not coming across as arrogant, it is just the way I compute it.
 
sphanna. No offense taken. I think you are right.
I should have devided 3.78 / 1.26=3.
I multiplied 3.78/.26=.98 and then subtracted that from 3.78. 3.78-.98=2.8.
My high school math is a little rusty. My speeds seemed to correspond well to my GPS so I never questioned it. I looked up a bunch of % formulas on line and nowhere was subtraction involved. Thanks for your help.
 
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About noise:

1. Maybe Float a motor engine mounts with hard rubber or compressed and mount hitting each other?

2. Rear transmission mount above the U Joint that is bottoming out on cross member due to problem with rear Float A Motor mount?

3. Front motor mount with wrong hardware?

a. JC Whitney spring setup or yoke nut too tight?

b. spring coils too large or springs too long so coils are binding when nut is tight?
 
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put a borg warner in my 29 w/3.78 rear and 21'' tiers, was a dog, couldn't use the OD untill i switched to 16''wires and 6:00 tires, lowered the ratio perfect, run all over NC mountains.
 
For those of you who have bought an over drive where did you buy yours,,, can you buy them directly from Mitchell or do you have to go threw a vendor like Hemmings and Macs.. Thanks.
 
I bought mine directly from Mitchell. Sue Mitchell is very pleasant to talk to and you can place your order with her. Last year there was a wait so you have to plan ahead.
Al
 
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