[tikiklubracing]

I need to see or locate a website that has pictures or drawings of the 7.5 and 8.5 casting tangs on the bottom of the rear housing. I hear you can tell them apart that way.

BIGGERISBETTER

[tikiklubracing]

I need to see or locate a website that has pictures or drawings of the 7.5 and 8.5 casting tangs on the bottom of the rear housing. I hear you can tell them apart that way.

BIGGERISBETTER

[Tom]

The 8.5 has the squared off tabs(they hang down below the cover)the cover is round.The 7.5 has half moon scallops in the casting below the cover and the cover is more squared off on the sides and top/bottom.You can see them clearly by looking at the rear from the back of the car.


Tom

[tikiklubracing]

I have a 7.5, mini spool rear, with the 1/2 moons only in my 78 race Catalina. (Yea the slow bracket 3) The one I.m trying to identify 78 Bonneville has tags that say 3.42 ratio & limited slip fluid only and has smaller 1/3 moons with about an 1 1/2" of squared off casting to the outsides of the smaller moons. Is this the 8.5?

BIGGERISBETTER

[This message was edited by tikiklubracing on January 05, 2003 at 09:22 PM.]

[This message was edited by tikiklubracing on January 05, 2003 at 09:24 PM.]

['ol Pinion head]

Several ways to tell if rear is dinky 7.5:

Look at the axle tubes. The 7.5's had smaller diam axle tube.

The 7.5's rear cover though round, does have aspects to it's shape of being squared off. The 7.5 rear cover is also smaller than that of an 8.5.

Most 7.5's have a cast "tang" which protrudes out of the housing above the pinion seal.

7.5 G-bodys, '82+ F-body rears, poss B-body rears had big steel plate type tabs for backing plates to bolt to with self tapping screws.

Problem is the 84-87 8.5 GN rearend also had the 7.5's small diam axle tubes. The 8.5 GN rearend will however have the large transfer lugs at 8 o'clock & 4 o'clock.

Not all 8.5's had the big squared off transfer lugs. There are two early bolt in axle applications of 8.5 housings that had same transfer lugs as earlier 12 bolts & 8.2 ten bolts. Can also guarantee, there are thousands of 8.5 rearends out there in service that have had their transfer lugs ground down to look like those on an 8.2 10 bolt. Disquising what you got is all part of the game

[tikiklubracing]

78-79 Bonnes came with 8.5s..A direct bolt in for Cats and Parieseanes(?) but use the drivshaft off the Bonne. also. Its about 1 1/2" shorter than the 7.5. I havn't seen any yet with c-clips. Oh! now the Cat is 412ci. 13.52 best ET. Not bad for .466 lift.