8 1/4 sure grip questions

[H22A4]

I've got an 8 1/4 2.94 open diff that I'll be upgrading with a sure grip and either 3.21 or 3.55 gears. My Scamp has a 318 that been bored and stroked to 327 running thru a 904 tranny. Aside from the usual red light race, it won't be taken to the drag strip or driven on the highway much; just a city cruiser taken out on weekends.

1. From the little bit of reading I've done, there are a few different "sure grip" units I could buy (Auburn, Detroit Truetrac, Powertrax, Dana). What is the difference between them and which one should I consider?

2. If you were in my shoes, what gear ratio (3.23 or 3.55) would you put in?


Tks....

 

[mr.318]

i've got the moparperformance 355 geared suregrip unit i like the moparparts seem to fit and work better long as your not doing alot of road trips go with the 355"s strong off the line compared to my old 2 something gears

 

[69signetv8]

Try to stay away from the cone posi if possible. look for the clutch type. For in town running around like you stated...I find 3.91 nice and they will get you across the street in a real hurry.

Here's a little more info (good & not so good)

http://www.usaimports.co.uk/Mopar_Tech_Pages/mopar_rear_ends.htm

 

[69signetv8]

Sorry, your staying with the 8.25? OK, I would go with the 3.55 gears


http://www.moparmusclemagazine.com/projectbuild/5148_custom_rear_end_install/

 

[PlumCrazyDuster]

you can get the center section out of an r/t dakota, most of em have 3.90s and theyll bolt right up, most of em have sure grips too if im not mistaken.

 

[rumblefish360]

PCDuster makes a good sugestion. Junk yards should have a few Dak's in them.
Gear ratio is stamped on the ring gear or on a tag on the rear cover bolt.

I'd do a 3.55 for the best of both worlds. 3.91's make Hwy. driving a bit of a drag. For a short time....OK. 1/2 max for me kind of thing unless it's to the strip or show/meet.

 

[340mopar]

You can use only certain year Dakota, Jeep, Durango, etc carriers, 8 1/4s from 1997 and up are 29 spline. You need a 1996 and earlier carrier because they are 27 spline like yours.


Chuck

 

[345man]

i had a 318, 904, with 3.55 gear very streetable and a good combo. the only difference is i had the low gear planetary set put in my trans. makes the car at take off more like a 3.91 but still the higher gear of a 3.55. just an opinion but works good. for highway and ocassional burnout the8.25 with posi will be just fine. have a good one :salute: