Will an LS3 water pump work?

[beeman]

Will the better-flowing LS3 water pump work at all? Or is conversion to the LS1 pump mandatory? Thanks!
Dave

[beeman]

I'm reading some mixed things about the water pump, but I'll switch to the LS1 pump just to be safe.

[VRaptor SpeedWorks, LLC]

The LS3 pump won't work without modifying the chassis. The difference is at the t-stat housing. The LS3 pump is a bit thicker in that area, so with the engine installed, the t-stat housing will be jammed up against the chassis tube.

[beeman]

I don't mind changing the chassis a little there - how much more space would you need? Thanks for the reply

[Roger Reid]

I believe the rounded section of the thermostat housing makes contact here.

[beeman]

Thanks for the picture, Roger. Not sure which pump to go with, I think my engine already has the ls3 water pump... Swap it out or mod the frame... Changing the frame is really easy, but I know it was computer designed so I wouldn't want to weaken that area...

[RumRunner]

Beeman,

Even with the LS1 water pump, the housing comes within about 1/8" of that frame rail. I used the Pfadt engine mounts for my GTM, which really limits the engine movement. I'd worry that the stock LS3 engine mounts allow enough movement that under quick engine revs that even the LS1 water pump may contact the rail.

-Michael

[beeman]

I'll look at that area of the frame and see if there's an easy way to move that tube. If anyone has any recommendations for modifying that beam, please post them.
Thanks again
Dave

[wallace18]

I would convert to the LS1 pump. I have no over heart issues at all with mine.

[beeman]

Does it hit the frame at all with revving the engine?
Is that specifically the Corvette ls1 pump?

[wallace18]

I have no issues at all. I did have to modify the frame near the A/C compressor . See my build thread. I did a LS3 in a 33 build for a customer recently and converted to LS1 pump due to using the Vintage air front runner system. No problems with either.

http://thefactoryfiveforum.com/showthread.php?23013-Wallace18-s-GTM-build-Thread
http://thefactoryfiveforum.com/showthread.php?24901-Richey-s-33-build-by-wallace18

[beeman]

Just looked at your build thread, Tom. I see where you notched the frame. Definitely a tight fit. I still haven't decided on what HVAC system I'm using, I have the Vintage Air system but probably won't use it PM me if anyone is interested in it. I'm actually going to try to use the Honda system mounted behind the passenger seat. The condenser is about half the size of typical and I think it will work using one of the GTM's rear air intakes. Thinking oil and tranny cooler on the opposite side.