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View Full Version : which Gear 3.55 Posi or 4.11?



austin552
12-19-2010, 07:41 PM
Mostly street with 17" rear wheels.
:hmm:

kryptik
12-19-2010, 09:57 PM
Details on engine, transmission, vehicle type/weight, and rear tire height please.

T/Aaron
12-31-2010, 01:59 PM
3.55 With 17" wheels and mostly street, then stick to street gears. I wouldn't use 4.11's unless it was mostly used for drag racing.

My427stang
12-31-2010, 06:22 PM
All depends on the tranny and tire/wheel combo. My FE with a TKO-600 has 4.10s and 4.30's would work great, but that same combo with a 4 speed was buzzy with 3.70's

wmhjr
01-01-2011, 04:21 AM
Without exception, everyone I know with a street car without an overdrive but with more than 3:73 gears wishes they had something else. Highway driving is impossible at reasonable speeds. Otoh, even with 3.73 in mine withnthe tko600, 1st gear is very low.

Samckitt
01-01-2011, 04:51 AM
If a single overdrive of around 75% I would not go any deeper than 3.73, if you have a dual overdrive like a T56 with a 50% ratio you can get away with something deeper. I have the T56 with 50% 6th gear & 3.42 gears & hardly ever use 6th unless I am on the interstate. The stock Monte had 3.73 gears with the 200r4 tranny & was good. I have 3.42 gears because that is what was in the Grand National rear when I got it. Eventually I would like to go with something between 3.73 & 4.10.

smith & sons
05-16-2011, 08:00 PM
Go to ringpinion.com then calculators.Enter your r&p ratio & tire diameter.This will give you your RPM at 60 mph.