Rear end conversion help!! 8.8" in an '89 Camaro

[4SPDFOX...+1]

A friend of mine just did a full H/C/I setup in his '89 IROC with a 350TPI mated to a T5 transmission. He is very concerned (rightly so) about the stock 7.5" rear end. I am selling my old 8.8" with 3.27 gears as a buddy gave me a free 8.8 with 3.73s. My old rear end actually is new, with only 20k miles on it from me, everything was brand new and I paid $900 for it. So we are trying to figure out how to swap the 8.8" fox rear end into his '89 Camaro. I'll break my concerns down into sections:

Suspension: Just gonna cut his brackets off and weld them on, i'm not concerned about the suspension aspect- we have access to a big shop with lots of fabrication tools.

Rear axle width: The 8.8" is 59.25" hub-to-hub while I have heard the GM 7.5" is 61.5". Using the 4-lug mustang axles is not an option for various reasons. The GM 7.5" axles are exactly 1" longer each and from what I have found are also 28 spline pieces (and he won't have to change wheels obviously because they are HIS axles) so if we can use his GM axles in my 8.8" ford rear end, that will make up for the 2" shorter width (since the axles are each 1" longer) and he can keep his wheels. Obviously the concerns are axle diameter and bearing location. Will the axles sit in the spider gears correctly, C-clips fit in the spider gears, axles sit in the bearings correctly, bearings be at the correct locations on the axles etc?

Yoke: I have a spare 8.8" pinion yoke with a small section of a driveshaft still attached. If the U-joint is the same size, I can press it out of the driveshaft and it will bolt to the GM-style driveshaft yoke via factory clamps and then obviously the other side will bolt up to the 8.8".

Brakes: Obviously if we (are able to) use his GM axles, they will protrude one inch further on each side meaning the brake plates will need 1" spacers which i'm sure we can fabricate, the question is will his drums work on the 8.8" brakes? If not, can we use his GM 7.5" brakes on the 8.8" rear end?

That covers it. In two weeks we are going to pull out his axles and yoke and brakes with the 8.8" rear end sitting right next to it and just play with everything and see what works. For now, if anyone has any information on this swap, i'd LOVE to hear all about it. Please help!!


P.S. Please no "you really should just use a 12-bolt or a Ford 9 inch" comments. The 8.8" is plenty strong enough and it's literally entirely brand new (housing, bearings, seals, gears, differential, bushings, everything is new) with only 20k miles from me. I paid $900 for it which was a deal for sure and i'm selling it to him as a favor for $300 (with at least 10-20 hours of my labor researching, fabricating and installing this thing included in the sale price).

[twistedstang]

The axle stickout past the housing would have to be the same as the 7.5 to use the same brakes. Probably not the same. The bot pattern on an 8.8 is way small so it would probably not have a large enough flat on it to match the 7.5 pattern. The 8.8 is gonna become the axle everyone goes to for swaps. Its cheap, plentiful, and strong. I think youd be better off going to aftermarket axles with the chevy pattern or having the stock 8.8 axles redrilled with the chevy pattern. Could have the same pattern redrilled into the 8.8 drum as well.

[banzaibullitt]

Aren't the 5 lug patterns the same? I think someone on here put Camaro rims on his Mustang.

[juiced306]

camaro is 5 on 4 3/4 and mustang is 5 on 4 1/2

[cb84capri]

have you guys looked into a borg warned 9 bolt? these came in those cars, supposedly pretty strong. just gotta find one with decent gears because apparently stuff is hard to find. there's one at a yard at G&G in phoenix according to car-part.com.

also, iirc, they didn't start using 28 spline axles in f-bodys until 91. i believe the earlier ones used 26 spline, and i'm not sure what came in the 9 bolt.

good luck with whatever you do.

cale

[4eyegt]

The axle stickout past the housing would have to be the same as the 7.5 to use the same brakes. Probably not the same. The bot pattern on an 8.8 is way small so it would probably not have a large enough flat on it to match the 7.5 pattern. The 8.8 is gonna become the axle everyone goes to for swaps. Its cheap, plentiful, and strong. I think youd be better off going to aftermarket axles with the chevy pattern or having the stock 8.8 axles redrilled with the chevy pattern. Could have the same pattern redrilled into the 8.8 drum as well.

may be too late but I think twisted is on to something here. I would look at getting 8.8 axles with the chevy bolt pattern. Then it would be 1" narrower and may allow wider wheel/tires to fit. Also the yoke issue really isn't an issue. Any driveshaft shop can swap ends on the shaft and allow you to run what ever U-joints you want.

Just had a brain fart. What about rear brakes? Are you staying drum or going disk? May have to figure a way to get the Chevy brakes to fit the Ford axle.