blueday

I'm in the middle of an LS3 swap. The guys who programmed my ecm and built my harness recommended using the 2wire alternator and let the ecm control the charging so I went with that setup.

What vehicles did the 2 wire alternators come on so I can get one at a parts store? Also, is the mounting any different than the alternator that came with my holley accessory setup (corvette spacing)?


Thanks for any advice you guys can provide.

Ryan

Project GatTagO

iTrader: (7)

This should work.

http://www.rockauto.com/en/moreinfo....446717&jsn=431

The Holley accessory alternator bracket uses a truck style alternator but on the Corvette balancer spacing...

Andrew

onefastrx7turbo

iTrader: (5)

Agree with Andrew. That unit is 145 amps. If you want a little more power, the DR44 is 160 amps in the same case.

http://www.rockauto.com/en/moreinfo....468192&jsn=715

blueday

You guys are great. Thanks for the information. I remember the holley information referenced the ctsv and the G8 being the same offset as the corvette brackets so I was digging around for info on the ctsv alternators. Glad yall replied and saved me some time and money.

blueday

No luck with that 165a alternator fitting on the holley accessory brackets. Mounting dimensions are off. I'm assuming the 145a alternator will be the same?

Any other options that yall are familiar with? I may try a G8 6.2L alternator if one of the parts stores has it.



Thanks,

Ryan

Project GatTagO

iTrader: (7)

Ryan,

That's very odd. Are you sure you have the Holley bracket? The Holley bracket looks almost identical to the C5/C6 OEM bracket. The main difference is that the Holley bracket uses the truck alternators which are less expensive that the Corvette alternators.

Andrew

B Gordon

I had a similar problem in reverse.
Bought the GM Performance accessory drive kit and it came with the Cadillac CTS-V alternator (2 wire) but my ECU is al LS1 version (1 wire). A huge pain in my rear to figure out a workable combination.

How about if you try the actual CTS-V alternator?
It does have a third mounting point but appears that it could utilize the normal two mounting points.
Or, how about trying a Corvette alternator from the year range that uses a 2 wire hookup?

No idea if it would do you any good but I do happen to have the CTS-V alternator mounting bracket that mounts the alternator low on the driver's side because I had to change to a different bracket when taking care of my problem.

Project GatTagO

iTrader: (7)

As I recall CTSV and Corvette have the same alternator mounts. The GM accessory drive uses a stock C6 corvette alternator mount. I actually have that on my GTO. I can take a rough measurement of the alternator mounting bolts. The Cougar has the Holley bracket. So I can measure both.

Just let me know.

Andrew

B Gordon

The pictures the OP posted appears to show the alternator mounted high on the driver's side. I seem to remember looking at Corvette's that also us that same high position.

The Cadillac CTS-V bracket mounts the alternator down low on the driver's side, which is the mounting location I utilized for my V8 Miata swap. The CTS-V uses a third mounting bolt that connects to the engine block just in front of the driver's side motor mount. The power steering pump is mounted on the drivers side high location where the Corvette mounts the alternator.
I could be wrong on the Corvette mounting location as I never compared the two side by side.

Project GatTagO

iTrader: (7)

There is alternator location and then there is the actual spacing for the mounting bolts.

Holley bracket uses the Corvette location but with the truck alternators.

B Gordon

To the OP, have you tried calling or e-mailing the Holley tech support people to see if they have a 2 wire alternator recommendation? They might have figured out the whole thing.

blueday

Now that you've questioned it and some research, it appears I have been sold the ac compr. bracket that is made by holley and the p/s, alternator bracket that looks to be a gm piece. I bought the setup used from a reputable c3 corvette company and was told it was a holley setup. Maybe they assumed it was all holley because of the 1 bracket but I'm gonna have to call and let them know. I don't expect them to refund me because it's been a few months, but do this to the wrong person and that could be a bad thing for them.

So now it looks like I'm in need of a 2wire alternator for a gm corvette type accessory bracket. Back to the store the other 2 go.

For future information I picked up a G8 gxp alternator from orielly and the mounting hole dimensions are the same as the 165A ac delco #335-1196 posted above (about 5-1/2" center to center) . The mounting dimension of the alternator that came with my setup (gm #25888970) is about 6-1/8".

blueday

Here's some pictures of the setup if it helps.

blueday

That'd be great Andrew if you can spare the time. I posted measurements of mine above. From our conversation here the g8 gxp alternator and holley bracket dimensions should be about 5-1/2". What looks to be the gm bracket that I have measures about 6-1/8". Dimensions are center of mounting hole to center.

Looks like I may have to go with a ctsv alternator (if dimns are right) or buy a holley bracket and keep the 165A posted above.

Thanks everyone for the advice. Seems like we're getting close to a solution.

79LS1FOX

iTrader: (11)

That is definitely a C6 alternator P/S mount bracket. I just took one off my car which has a 2007 C6 engine in it.

blueday

Thanks for the help......can anyone advise what 2 wire alternator I would need for the gm corvette alternator bracket? Sounds like a ctsv would work but looks like itbwould have an extra btacket on it? Or would I be better off in the long run ordering the holley alternator bracket?

79LS1FOX

iTrader: (11)

Are you opposed to the vette alt because of price? if not I would just get the vette alt and be done with it. They do seem a little pricy but the also have a feature none of the others do, it has a clutch mechanism on the drive pulley which lets it freewheel on shut down?

Project GatTagO

iTrader: (7)

If you have a Corvette bracket, then I would just get a Corvette alternator.

Andrew

blueday

I thought the c6 vette alternator didn't have the 2 wire setup? O

Project GatTagO

iTrader: (7)

I just looked on RockAuto and it looks like you are correct. All of the C6 alternators have a 4 wire plug....hmmm...

I don't know that a CTSV alternator will fit on the Corvette bracket. At this point, it might be easier to get the Holley bracket (not that expensive) and use that DR44 truck alternator that you bought.

I just measured my Holley bracket and the bolt spacing for the alternator appears to be about 5 7/16".

http://documents.holley.com/199r10607rev6.pdf

See page 7.

Andrew