I am in the middle of doing this swap but the bolt pattern on the rear end flange is quite a bit different than the LS1 backing plate and I am trying to figure the best way to mount them. The welds spill over to the area behind the flange making drilling new holes rather tricky. I could drill out the backing plate but I don't think would be the best quality solution. Anyone with experience here would be of great help. Thanks

 

I know someone's sig around here said they did it. You might want to check with the socal region board.

 

I have done it. I don't have any pictures though.
What I did was elongate the bolt holes, the two top ones up and the two bottom ones down at an angle. Then I used a sleeve to center the backing plate on the housing. The biggest problem lies with the spacer that needs to be made the thickness of the backing plate and installed between the flange and the bearing seal (it pushes the axle into place).

 

Thanks for the prompt replies here guys. Hey Dyno Don could you elaborate some more on your spacer. I am at the hole stage now and thought about elongating the holes but I was worried it would allow too much play for the stress that it will receive from the twisting effect of the brakes. Also the welds on the backside of the flange cover part of the area where the bolts will have to go so I guess I will have to grind some of them out. This spacer though... I have not gotten that far so I really do not understand yet exactly what this is for.

 

Okay now I have had coffee and am thinking straight. Dyno Don Did you elongate the holes in the bracket or the rear? I think I can elongate the holes in the bracket and make little filler pluigs to take up the slop like the old school cam degree plugs that fit into the large timing gear. This is what I am going to try today but I will likely understnad more about your spacer when I return. Also what is this centering sleeve all about? No net access at the shop so I hope to hear back from you and anyone else who has advice. Thanks again.

 

The holes in the brkt. The big hole fits over the housing loose, I put a sleeve over the housing to make the brkt. fit tight thereby centering it. The brkt. is about .250 thick so the spacer needs to be that amount. If you notice the flange pushes the bearing and seal in, once you put on the brkt. the flange will lack about .250 of pushing in the bearing and seal and axle will pull in and out, hence the spacer to hold it in tight. It's about 2 9/16ths X 1/4"(or the width of the bearing and the thickness of the brkt.)
HTH

 

Ahh yes after working on it yesterday again I can see clearly what you mean by the spacer to compress the seal. One difference though is on my dif the hole in the bracket matches the dia of the rear perfectly so no sleeve needed. Strange how mine is different. As far as the spacer goes I think I will make one up and cut out a section just large enough to fit over the axle so I do not have to remove the bearing and then weld it back together and to the axle plate so that it does not move or fall out. How did you go about this? Thanks againjavascript:smilie('')

 

Congratulations...I think you have it now Enjoy!

 

Whooaa!! Bessie yee haw!

 

Got it figured out pretty well now. This link will help anyine else out quite a bit more.

https://www.thirdgen.org/techbb2/sho...hreadid=215729