forum.jdrace.com

Just have some question on a hbody I just purchasd.
It is an H body differential with 5 lug s10 axles, it is I believe 2.93 gear. So I guess my question is. Would the ring and pinion have to be for/from the vega differential? I cant find where this gear was used in the other hbodys. I was told it was a 2.93 and it looks like it is according to turning the drive shaft with the wheel trick. Its just short of 3 turns on the driveshaft.
The car also has the 4 cyl saginaw which has the steep 3.50 1st gear. The car has no traction in 1st or 2nd. Would it be wise to change the rear gear ratio to a 2.73? Im already getting traction bars so I figured the slightly higher gear plus the bars would help quite a bit. Not really wanting to change trannys right now and the gas mileage would be a little better also. Down the road I will be getting a different tranny and then will drop the gear again to prob 3.23. Ive read that the hbody housing could be modified to fit a larger g or f body pinion. What is the spline count on a hbody pinion?

Thanks,
Bill

Ok well will start at the beginning here.
-2.92 /2.93 is a correct ratio. If you remove the rear cover the tooth count will be stamed on the ring gear outer diameter edge along with the ring part number and date code tooth count will be (41 ring and 14 pinion)
-If you have a v8 YOU WILL NEVER get any traction...lol. PERIOD.
-Traction bars do not give you traction SLICKS GIVE YOU TRACTION. Ladder bars only control the pinion angle from getting out of whack and keeps it stable from making the rear wheel hop etc.
-I do not know the cam shaft or engine combo to be able to tell you if your mileage will get better with a gear swap. Your cruise RPM will lower with the 2.73 swap.
-H-Body Modification - I would NOT do this as there is just not a sufficient amount of material to increase the inner race pocket to use the same race as all the rest of the 7.5 rears. PLUS it is BIGGER money than machining the pinion gear to fit the original bearing set H-bodys cam with.

This is a easy rear to upgrade with off the shelf parts and the 7.5 rear will handle the power on the street and even some reasonable track time . Keep it simple and use what is already available.

axles you have, any 7.5 posi will fit the H-body rear, and the gears are easily machined for 40.00 all the bearings are available and easy to get.

Jim Mitschke