svMike Posted July 9, 2012 Share Posted July 9, 2012 I have my LS3 on an engine stand and while mocking up the FEAD, I found that the alternator hits the 240Z k-member/JCI engine mount. I attached pictures to show the alternator from the front, side and where it hits the k-member. The engine, alternator and bracket is an LS3 from a 2009 G8 GXP. I plan to only run the alt and water pump from the crank. It looks like I need to swap to the smaller 93-02 LS1 Camaro/Firebird alternator, does that sound right? Can I reuse my alternator bracket? Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted July 9, 2012 Share Posted July 9, 2012 I went thru this same problem recently. Ya' gotta go to the F-body alternator. The rear bracket is like $9 from the dealer, new so go ahead and order the bolts too. You should be able to retain your current front bracket. I tried everything to avoid changing to the F-body alternator (even cut the crap out of my left-side motor mount), but in the end I switched. My swap was from an LS2. I don't know if (or if not) the fore and aft spacing of the accessories will be compatible. There have not been many LS3 swaps. Send a PM to alainburon for other LS3-related issues. He is about 6-months ahead of you on his LS3 project. Do you have any problems with the spacing between the crank pulley and the steering rack? If so, the solution is an underdrive pulley, but that moves your serpentine belt very close to the lower bracket bolt on the front alternator bracket. Remember to tell your electrical harness modifier that you switched alternators so that plug can be re-wired. Quote Link to comment Share on other sites More sharing options...
svMike Posted July 10, 2012 Author Share Posted July 10, 2012 (edited) I went thru this same problem recently. Ya' gotta go to the F-body alternator. The rear bracket is like $9 from the dealer, new so go ahead and order the bolts too. You should be able to retain your current front bracket. I tried everything to avoid changing to the F-body alternator (even cut the crap out of my left-side motor mount), but in the end I switched. My swap was from an LS2. I don't know if (or if not) the fore and aft spacing of the accessories will be compatible. There have not been many LS3 swaps. Send a PM to alainburon for other LS3-related issues. He is about 6-months ahead of you on his LS3 project. Do you have any problems with the spacing between the crank pulley and the steering rack? If so, the solution is an underdrive pulley, but that moves your serpentine belt very close to the lower bracket bolt on the front alternator bracket. Remember to tell your electrical harness modifier that you switched alternators so that plug can be re-wired. Thanks. I was hoping to reuse the alternator that I have, but there is no way to fit that sucker in there. Could you post a picture of your F-body alternator and bracket? My water pump and crank pulley are from G8 GXP, I'll post part numbers when I get home. I think they are the same offset as the LS3 Corvettes, which means I'll need to trim 3/4" from the alt bracket to make the F-body alternator work with the Corvette offset. I've PM'd a few people asking how/what they used to get their LS3 alternators mounted, I'm waiting to hear back. I haven't checked for steering rack clearance yet, I'm waiting for my new oil pump to come in and replace that before I install the crank pulley. I'll measure that and post pictures, might be a while, I just ordered the oil pump today. I already have an engine harness, but it looks like it is fairly straightforward to go from a 4-wire to 2-wire. Edited July 10, 2012 by svMike Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted July 10, 2012 Share Posted July 10, 2012 For pictures, go to my thread titled Project Mentor Wanted in the Gen III forum. There are pictures of the alternator on pages 2,3,5. Boy from Oz sent me some super pictures on one of those pages as well. Quote Link to comment Share on other sites More sharing options...
svMike Posted July 10, 2012 Author Share Posted July 10, 2012 (edited) For pictures, go to my thread titled Project Mentor Wanted in the Gen III forum. There are pictures of the alternator on pages 2,3,5. Boy from Oz sent me some super pictures on one of those pages as well. Thanks, I'll look through your pics. The G8 GXP crank pulley is part number 12635649. This interchanges with LS3 Corvettes, so my accessory drive is the closer block offset, not the F-body offset, I also laid the steering rack on the k-member and checked for clearance against the crank pulley. There was about 3" of clearance, but that will shrink when the engine weight sits on the k-member, but I think there is still enough room there. I looked at LS1tech for FEAD arrangements and I think it might be possible to make an extension bracket from the bottom of the alt bracket to the bottom of the alt. This will get the alt to sit like the attached picture. If that works, that belt arrangement should work. Edited July 10, 2012 by svMike Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.