LS1 reverse cooling

Anyone seen this....
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Found it while looking for a flow diagram for the LS1 vette pump if anyone knows of a flow diagram out there.

Anyone have a drawing/flow chart of the LS1 water pump?
From the old truck pump I have I can't tell which way the water flows and exits. I am not sure if I can just run without a Thermostat without messing up the flow ports to the heater or not. I thought someone posted that the larger port on the pump comes from the heater core return?

I may have to make an inner block-off plate, I'm not sure of it as of now....

(edit): I'm sure it would benefit from reverse cooling, but i doubt enough to justify the hassles. Only one way to find out!

I posted the question in the tech section over on LS1.com
I am really only interested in making sure my heater will work if I completely remove the T-stat from the pump or if I need to put in a block-off plate on the inside somehow between the two heater ports... But it is interesting that a reverse vein propeller could be installed into the pump housing to make the water flow in the opposite direction... Would this be a simple solution for Reverse cooling? The guys over there still haven't stated concretely if the heads or block is cooled first on these motors....

The coolant enters through the lower right hose, into the tstat housing, past the tstat when at operating temperature and into the block and surrounds the cylinder bores. Then, it goes up through the head gasket and into the head. After cooling the heads, the coolant then goes back to the pump and through the upper radiator hose and into the radiator. So in short, the coolant goes UP in the engine and down in the radiator.

The reason for reverse cooling was antidetonation for the high compression LT1 engines and for heating the oil of the resulting hotter cylinder bores for less friction. This was simply a fix by GM for the hotter running LT engines due to high compression. The biggest problem was that the coolant was flowing down throughout the engine and air/steam was flowing ofcourse up causing hot spots along the cylinder bores and thus....detonation and keeping the system completely airless was very difficult.

but, the LS1 has lower compression and really well designed combustion chambers/heads as well as a severly reworked block including the water jackets.... so they scrapped the reverse cooling for the small block due to these changes...no need.

....and they lost a law suit.....http://www.autoblog.com/2006/06/13/inventor-may-win-big-in-suit-against-gm/

LOL, didn't know they finally lost that lawsuit. I read up on it a while ago and it was some total BS that they pulled.

The point of reverse cooling being that you could run a few more degrees of timing by cooling the cylinder heads first with cooler coolant.

And on that note...when is one of you going to give up on these "5hp here, 5hp there..." ideas and just slap a damn turbo on the car? It would simplify exhaust routing drastically, and there is room (i've considered it!). For all the hours spent looking at equal length crossover header designs, reverse cooling, etc....you would make a ton more power and get a lot more props with a simple turbo setup!!

I am only looking to do a mod to the LS water pump and remove the thermostat. On the last V8 swap I did to a 2.8l S-10, all I did was remove the T-stat and did not change to a larger radiator. All my overheating issues went away. In the winter, I just reinstalled the T-stat and the heater blew nice n hot and engine never overheated. My theory is the stock 944 NA radiator with the T-stat removed would be the best cooling set-up and obviously the easiest. The inner port hole between the heater ports on the LS1 pump can be blocked off. I have read elswhere that a 1/2" hole is drilled in a freeze plug and installed. I also see that the 160deg T-stats have 4 small holes drilled in that block-off plate. The only reason I can see why GM put that small rear block-off plate(spring loaded) was in case the radiator (even heater core) were to be clogged, the coolant would just recirculate within the block. Looking at the Truck Pump, the inner port hole could be enirely blocked off with an epoxy'ed freeze plug or the stock T-stat could simply have the upper piston drilled/removed and the heater would function normally and the water velocity would remain constant and increase with RPMs.

I removed the back cover from the truck WP to double check the flow route of this pump which should be exactly the same as all the LS pump routings. From what I see, if that inner port hole is blocked off completely and the T-stat removed the coolant velocity would be higher going to the top radiator and cool much better.

I didnt think people were having cooling problems with the LS series engines. I am new to the LS engines so is this whats happening? The LT was a PITA to cool so I was hoping the LS was a much cooler running engine.

No, no cooling issues with the LS motors. He's strictly talking for performance gains, i believe.

The whole point is leaving the NA radiator and fans untouched....I bought the rear steam block off kit for the LS1 which is perfect for the LS1 intake that I installed on the truck motor.....Now Where does the front steam tube go to on the 944 radiator/overflow tank then?

I just "T"d mine in to the bleeder hose coming out of the top driver side of the radiator and going in to the overflow tank.

Thanks Porch. Wasn't sure about that detail. Also I assume the smaller dia. heater core tube on the firewall is the influent to the core and large dia. is the return back to the water pump?

I'll go take a look in a bit, but if memory serves me correctly i just ran the 5/8" outlet from the water pump in to the 5/8" inlet on the heater box, and same with the 3/4". I did a write-up on it on PHB a while ago, i wonder if it made it into the manual? I need to order those one of these days once my car stops eating money :/