GTO LS2 vs. Corvette LS2
I may have made a pretty startling discovery. I think the Corvette and GTO LS2s have differently cast blocks. I tried to fit a Vette motor mount bracket onto a GTO LS2 and it doesn't fit due to a protrusion for mounting the GTO AC compressor. The GTO motor mount bracket on the passenger side is differently designed to fit over this extruded bung, though the Vette and GTO have the same driver side motor mount bracket.
Corvette Bracket On GTO LS2:
GTO Bracket On GTO LS2:
As you can see, the place where it hits is a part of the block. In order for the Vette mount to fit, the block itself would have to not have that protrusion. The Vettes do have a different way of mounting the compressor, but I haven't been able to find any pictures of exactly how, or pictures without a compressor.
Corvette Bracket On GTO LS2:
GTO Bracket On GTO LS2:
As you can see, the place where it hits is a part of the block. In order for the Vette mount to fit, the block itself would have to not have that protrusion. The Vettes do have a different way of mounting the compressor, but I haven't been able to find any pictures of exactly how, or pictures without a compressor.
TECH Enthusiast
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From: Perth, Australia
Thats not all mate.
Get a square and put it like this on the GTO bracket, then do the same for the Corvette bracket.
GTO blocks gets mounted offset in relation to car centreline (distance at the blue arrows is approx 3/4"). I suspect the sides of the GTO block where the brackets mount are not machined parallel to the crankshaft centreline.
Pic of a Corvette LS2 block
Get a square and put it like this on the GTO bracket, then do the same for the Corvette bracket.
GTO blocks gets mounted offset in relation to car centreline (distance at the blue arrows is approx 3/4"). I suspect the sides of the GTO block where the brackets mount are not machined parallel to the crankshaft centreline.
Pic of a Corvette LS2 block
Now I'm only getting more confused. All of the blocks you've posted look to have the same mounting points, except one picture.
http://i2.photobucket.com/albums/y20...3_ls2_06_z.jpg
See how it only has 2 of the three taps for bolting on the compressor? What gives?!?!?
http://i2.photobucket.com/albums/y20...3_ls2_06_z.jpg
See how it only has 2 of the three taps for bolting on the compressor? What gives?!?!?
Teching In
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Now I'm only getting more confused. All of the blocks you've posted look to have the same mounting points, except one picture.
http://i2.photobucket.com/albums/y20...3_ls2_06_z.jpg
See how it only has 2 of the three taps for bolting on the compressor? What gives?!?!?
http://i2.photobucket.com/albums/y20...3_ls2_06_z.jpg
See how it only has 2 of the three taps for bolting on the compressor? What gives?!?!?
Actually, I think the RX7 subframes (yours and Hinsons) put the mounting brackets on the opposite sides from their stock locations, which would mean technically, you (and now I, after guessing the same thing the other night) have them on backwards. I hope I'm right on this, otherwise I'm even more lost.
Edit: I made sure, the RX7 guys are indeed backwards.
Anyways, still seems odd that there would be two different castings for the LS2 block.
Edit: I made sure, the RX7 guys are indeed backwards.
Anyways, still seems odd that there would be two different castings for the LS2 block. Last edited by Troux; Dec 15, 2008 at 09:03 PM.
Teching In
Joined: Aug 2008
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You are right. They would be backwards for a vette or gto, and your swap requires them to go the other way, which takes care of your clearance issue.
With that being said, you should be able to install the motor with out any other issues.
With that being said, you should be able to install the motor with out any other issues.
Staging Lane
Joined: Feb 2010
Posts: 57
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From: Corpus Christi, TX
Sorry for the thread revival, but I've got a quick question about accessory set-ups. I've got a 98 LS1 and I need to run the shorter water pump pulley for radiator clearance on my swap. If I run the LS2 or LS7 water pump with the shorter pulley, what accessory drive pulleys can I retain/what other LS2/LS7/L76 pulleys do I need to run? Thanks in advance.
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Hey,
I'm in Corpus - and have some parts that you can look at to see how they work.
Bottom line - with the LS2 water pump,(not the LS3), its close, but you can run the Camaro/GTO setups - its close to the edge of the pulley. Check out v8rx7forum.com for some guys who ran those setups. I have a LS2 water pump, but I'm running the Corvette/ G8 accy. Mine is going into a 94 RX7,(motor is a LS2).
-Bob
I'm in Corpus - and have some parts that you can look at to see how they work.
Bottom line - with the LS2 water pump,(not the LS3), its close, but you can run the Camaro/GTO setups - its close to the edge of the pulley. Check out v8rx7forum.com for some guys who ran those setups. I have a LS2 water pump, but I'm running the Corvette/ G8 accy. Mine is going into a 94 RX7,(motor is a LS2).
-Bob
Staging Lane
Joined: Feb 2010
Posts: 57
Likes: 0
From: Corpus Christi, TX
Hey,
I'm in Corpus - and have some parts that you can look at to see how they work.
Bottom line - with the LS2 water pump,(not the LS3), its close, but you can run the Camaro/GTO setups - its close to the edge of the pulley. Check out v8rx7forum.com for some guys who ran those setups. I have a LS2 water pump, but I'm running the Corvette/ G8 accy. Mine is going into a 94 RX7,(motor is a LS2).
-Bob
I'm in Corpus - and have some parts that you can look at to see how they work.
Bottom line - with the LS2 water pump,(not the LS3), its close, but you can run the Camaro/GTO setups - its close to the edge of the pulley. Check out v8rx7forum.com for some guys who ran those setups. I have a LS2 water pump, but I'm running the Corvette/ G8 accy. Mine is going into a 94 RX7,(motor is a LS2).
-Bob
I expect to have it fully finished in the next month,(end of April/early may). Engine is assembled, working on the interior of the RX-7 right now - finalizing a few things.
I have a LS2 water pump if you want to test fit to see how it works - might keep you from changing out all the accessories,(which means $$$$).
I have a LS2 water pump if you want to test fit to see how it works - might keep you from changing out all the accessories,(which means $$$$).
Staging Lane
Joined: Feb 2010
Posts: 57
Likes: 0
From: Corpus Christi, TX
I expect to have it fully finished in the next month,(end of April/early may). Engine is assembled, working on the interior of the RX-7 right now - finalizing a few things.
I have a LS2 water pump if you want to test fit to see how it works - might keep you from changing out all the accessories,(which means $$$$).
I have a LS2 water pump if you want to test fit to see how it works - might keep you from changing out all the accessories,(which means $$$$).
Teching In
Joined: Mar 2010
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From: Nebraska
I have an '06 GTO LS2, and I suppose this question is academic as I'll know the answer shortly when my already ordered Corvette LS2 accessory kit gets here tomorrow, but anybody know if the Corvette accessories will work still using the stock GTO water pump & pulley? Will the belt line up properly? It looks like they're the same with the only exception being the longer pulley on the GTO LS2. From the pic's I've seen my eyeball says the diameter is the same... ?
TECH Enthusiast
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From: Perth, Australia
I have an '06 GTO LS2, and I suppose this question is academic as I'll know the answer shortly when my already ordered Corvette LS2 accessory kit gets here tomorrow, but anybody know if the Corvette accessories will work still using the stock GTO water pump & pulley? Will the belt line up properly? It looks like they're the same with the only exception being the longer pulley on the GTO LS2. From the pic's I've seen my eyeball says the diameter is the same... ?
The GTO crank pulley puts both belts 3/4" out further than a Corvette crank pulley would.
Run all GTO pulleys & accessories or all Corvette pulleys and accessories.
1=Corvette, 2=GTO/Fbody, 3=Truck
See how the webs inside the GTO crank pulley splay outwards
The Corvette crank pulley has vertical webs.
Teching In
Joined: Mar 2010
Posts: 24
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From: Nebraska
Thanks for the info, even if it wasn't exactly what I wanted to hear. The water pumps themselves are the same though, correct? The only difference is the pulley? This is where you have to say yes or I go insane...
TECH Enthusiast
Joined: May 2005
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From: Perth, Australia
The GTO waterpump shaft is longer and the domed black pulley extends further forward than Corvette.
You could probably get away with running a Corvette crank balancer with a GTO waterpump...the GTO WP pulley should be wide enough to allow the belt to run 3/4" in closer to your block than its designed for.
{You cannot get away with the other way around, Corvette WP and GTO crank balancer wont work}
You could probably get away with running a Corvette crank balancer with a GTO waterpump...the GTO WP pulley should be wide enough to allow the belt to run 3/4" in closer to your block than its designed for.
{You cannot get away with the other way around, Corvette WP and GTO crank balancer wont work}
If you are referring to the pictures above - i.e. the LS1 style pump and the LS2 style pump - yes, fundamentally they are the same except the pulley. Supposedly the LS2 and more so on the LS3 the impeller/bearings were improved. But you can run the LS2 pump pictured above on an LS1 F-body/GTO accessory engine.
Teching In
Joined: Mar 2010
Posts: 24
Likes: 0
From: Nebraska
The GTO waterpump shaft is longer and the domed black pulley extends further forward than Corvette.
You could probably get away with running a Corvette crank balancer with a GTO waterpump...the GTO WP pulley should be wide enough to allow the belt to run 3/4" in closer to your block than its designed for.
{You cannot get away with the other way around, Corvette WP and GTO crank balancer wont work}
You could probably get away with running a Corvette crank balancer with a GTO waterpump...the GTO WP pulley should be wide enough to allow the belt to run 3/4" in closer to your block than its designed for.
{You cannot get away with the other way around, Corvette WP and GTO crank balancer wont work}