Shorter alternator for LS3 in 240Z
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Shorter alternator for LS3 in 240Z I have my LS3 on an engine stand and while mocking up the FEAD, I found that the alternator hits my k-member/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 a shorter alternator, can anyone suggest one?
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 a shorter alternator, can anyone suggest one?
I thought it was pretty common for guys with GTO alternators to swap in an F body alternator to clear the John's cars mounts. I would start with that. However from that pic your set up might be more challenging.
There are several relocation kits that allow you to move the alternator above either head. I ended up making my own bracket to mount a denso alternator to the side of the driver side head. I can get by with a smaller amperage since I'm not running EFI.
There are several relocation kits that allow you to move the alternator above either head. I ended up making my own bracket to mount a denso alternator to the side of the driver side head. I can get by with a smaller amperage since I'm not running EFI.
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Any more info on your Denso setup? I'd rather make my own bracket than buy another alternator.
You're right, most folks at HybridZ are using the LS1 Fbody alternator.
It looks like that will fit, so I will give it a shot if I can't figure out a way to use my alternator.
You're right, most folks at HybridZ are using the LS1 Fbody alternator.
It looks like that will fit, so I will give it a shot if I can't figure out a way to use my alternator.
I have an LS2 with a vette WP and crank pulley. I use the stock vette tensioner. Here is a picture. I have since switched to a half inch longer belt, part number 5060650. I got the alternator off a 91 celica and scored a pulley from a 96 supra. The alternator is right next to the strut tower so I needed the denso unit that had a power lug coming straight out the back and not the side. This one is only 85 amps which is plenty for a carb'd motor. Denso alternators are a good bit smaller than GM ones in pretty much every dimension. I doubt you could mount a GM alternator in this position. If your motor is up and forward a bit it might put the alternator in front of the strut tower
I couldn't use an F body mount cause I got the motor a good bit lower and farther back than the John's cars kit does. Having the vette accessories push everything back 3/4 of an inch didn't help either. There was no way to clear the steering gear.
This is a good spot for the alt on a Zed. I replaced the thing with a rebuilt just last week. A 10 minute job.
If you want to reuse the alt you have look into kwik performance brackets. They put it above the dirver's side head. If you search on here you will find a kit for mounting an alternator above the passenger's side head that you can probably copy.
I couldn't use an F body mount cause I got the motor a good bit lower and farther back than the John's cars kit does. Having the vette accessories push everything back 3/4 of an inch didn't help either. There was no way to clear the steering gear.
This is a good spot for the alt on a Zed. I replaced the thing with a rebuilt just last week. A 10 minute job.
If you want to reuse the alt you have look into kwik performance brackets. They put it above the dirver's side head. If you search on here you will find a kit for mounting an alternator above the passenger's side head that you can probably copy.
Last edited by Pop N Wood; Jul 9, 2012 at 07:25 PM.
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I have an LS2 with a vette WP and crank pulley. I use the stock vette tensioner. Here is a picture. I have since switched to a half inch longer belt, part number 5060650. I got the alternator off a 91 celica and scored a pulley from a 96 supra. I needed the denso unit that had a power lug coming straight out the back. This one is only 85 amps which is plenty for a carb'd motor. Denso alternators are a good bit smaller than GM ones in pretty much every dimension. I couldn't use an F body mount in cause I got the motor a good bit lower and farther back than the John's cars kit does. Having the vette accessories push everything back 3/4 of an inch didn't help either.
Last edited by svMike; Jul 10, 2012 at 01:28 PM. Reason: snip pic from quote
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I don't claim to be smarter than anyone but I may have a bit more experience at some things and I'm willing to share my knowledge. 
Take a look at this post from my Thunderbird build. About halfway down you can see the bracket I built that puts the alternator where the AC compressor was.
Take a look at this post from my Thunderbird build. About halfway down you can see the bracket I built that puts the alternator where the AC compressor was.
Last edited by gofastwclass; Jul 9, 2012 at 08:58 PM. Reason: bloody typing...
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Teching In
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I don't claim to be smarter than anyone but I may have a bit more experience at some things and I'm willing to share my knowledge.
Take a look at this post from my Thunderbird build. About halfway down you can see the bracket I built that puts the alternator where the AC compressor was.
Take a look at this post from my Thunderbird build. About halfway down you can see the bracket I built that puts the alternator where the AC compressor was.
I'll keep your alt bracket in mind, how thick is that steel?
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alt bracket extension I was (still) trying to get my alternator to fit last night when I thought of a simple fix: make an extension from the bottom of the bracket to the bottom of the alternator.
I attached a pic, the yellow bar would be the extension bracket. The alt would sit slightly higher to clear the k-member, but you get the idea.
Thoughts?
I attached a pic, the yellow bar would be the extension bracket. The alt would sit slightly higher to clear the k-member, but you get the idea.
Thoughts?
That would put the alternator in contact with the strut on my Zed.
Your motor looks a good bit higher but I still think that will have trouble clearing the frame rails on a 240Z. Even if it does it is probably hangs so far away from the motor that it will intrude on the fender sheet metal.
Your motor looks a good bit higher but I still think that will have trouble clearing the frame rails on a 240Z. Even if it does it is probably hangs so far away from the motor that it will intrude on the fender sheet metal.
Last edited by Pop N Wood; Jul 10, 2012 at 03:45 PM.
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That would put the alternator in contact with the strut on my Zed.
Your motor looks a good bit higher but I still think that will have trouble clearing the frame rails on a 240Z. Even if it does it is probably hangs so far away from the motor that it will intrude on the fender sheet metal.
Your motor looks a good bit higher but I still think that will have trouble clearing the frame rails on a 240Z. Even if it does it is probably hangs so far away from the motor that it will intrude on the fender sheet metal.
I don't claim to be smarter than anyone but I may have a bit more experience at some things and I'm willing to share my knowledge.
Take a look at this post from my Thunderbird build. About halfway down you can see the bracket I built that puts the alternator where the AC compressor was.
Take a look at this post from my Thunderbird build. About halfway down you can see the bracket I built that puts the alternator where the AC compressor was.
If that mounts the alternator far enough forward it might work for the OP, but my guess is the back of the alt will still hit the mounts. Seems like a mirror of the other side.
If you have questions, feel free to ask. If I know, I'll share.
Nice work. Did you have a clear picture of the belt routing? I assume it hooks into a tensioner somehow.
If that mounts the alternator far enough forward it might work for the OP, but my guess is the back of the alt will still hit the mounts. Seems like a mirror of the other side.
If that mounts the alternator far enough forward it might work for the OP, but my guess is the back of the alt will still hit the mounts. Seems like a mirror of the other side.
I guess my question was whether you used the back crank pulley for the AC only like a vette does or looped it into the front pulley along with the rest of the accessories. Sounds like you hooked into the front pulley.
I will say one thing, running just a low amp alternator and WP makes belt wrap a lot less critical. I was a little worried about that at first but no problems that I can tell. Not much load I guess.
I originally made my brackets out of 1/8 inch steel and got stranded when the damn thing broke. Part of the problem was having the belt a tad too short. I remade everything out of 3/16 steel and switched to a longer belt and now no issues. Your brackets are a good bit different then mine so I wouldn't expect you to have the same issue.
I will say one thing, running just a low amp alternator and WP makes belt wrap a lot less critical. I was a little worried about that at first but no problems that I can tell. Not much load I guess.
I originally made my brackets out of 1/8 inch steel and got stranded when the damn thing broke. Part of the problem was having the belt a tad too short. I remade everything out of 3/16 steel and switched to a longer belt and now no issues. Your brackets are a good bit different then mine so I wouldn't expect you to have the same issue.
Correct, everything is on the front groove in the pulley. Sorry I didn't make that clear. I didn't use the rear pulley because 4 groove belts don't have the length options of their six rib brothers.
Beyond being very short, it's hard to tell in the photos but the bracket has front and back mounting tabs and a small back brace on it. Using thicker metal obviously allows you to eliminate braces or make the bracket longer which I didn't need to do. It didn't flex at all when mounted to the engine and pried against so I felt confident it wasn't going anywhere. It's also held up to three years (35K+) of abuse and one wreck almost two years ago.
Beyond being very short, it's hard to tell in the photos but the bracket has front and back mounting tabs and a small back brace on it. Using thicker metal obviously allows you to eliminate braces or make the bracket longer which I didn't need to do. It didn't flex at all when mounted to the engine and pried against so I felt confident it wasn't going anywhere. It's also held up to three years (35K+) of abuse and one wreck almost two years ago.
