FWD vs RWD Cooling System

[johnbmaxwell]

I'm preping a 3400 FWD engine for RWD duty. Converting to S10 2.8 accessory drive. I want to turn the intake around to put the thermostat housing and throttle body in the front. I'm a little concerned about the effects on the cooling system. From O'reilly Auto Parts site, I pulled the pictures of the head gaskets for the 3400 engine as well as the Camaro 3.4. They seem very similar with the 3.4 head gaskets having a couple of extra holes.

Has anyone attemped turning the 3400 intake around? Results? Head gaskets used?

Thanks

John Maxwell

[Mars]

A bunch of us have done it. No issues. Stock gaskets.

[geoffinbc]

The RWD gaskets do have extra holes at the back of the head gasket so that water flows from the back of the head to the front. The FWD engines do not need this because the water pump and thermostat are on the opposite side of the motor.

So I would use RWD gaskets if possible or make the extra holes in the 3400 gasket. Or look into 4 corner cooling by plumbing in lines from the rear of the manifold to the thermostat housing.

[trotterlg]

I am also considering turning around the lower intake on a 3.1. It appears there are blocked off passages that could be opened up. If this were just turned around wouldn't the water just want to go into the front of the engine and right back out the front where the passages are? With the intake i the stock position the water has to go into the heads, through the passages to the rear (flywheel end) of the engine and out.

[geoffinbc]

thats why you want to encourage water to the back of the motor. Up into the heads and then forward. So you need to make sure the larger holes in the head gasket are in the rear. The size and amount of holes in the head gaskets are all you have to influence water flow.

[trotterlg]

Normally the 3.1 FWD water goes in the front and out the back, if you turn around the intake it would go in the front and out the front, I don't see any circulation to the rear of the engine that way. That is why I was thinking of opening the other water passages you see in the intake and blocking the ones that are open now. Larry

[geoffinbc]

No that not what you want to do. You are forgetting about the head gasket! There are small holes in every water jacket on all pistons so water gan go straight up. But the largest holes on a RWD setup are at the back where the majority of the water flows up to the head and forward to the thermostat housing.


So th water flows in the front of the block on each side. The majority if forced to the back and up through the large holes in the back of the head gasket. Then the water flows up at the back the the head and makes its way forward to the coolant crossover and out the thermostat opening to the rad and around again.

If you open up the holes in the rear of the manifold and block the front you wont get full flow through the heads. Now 4 corner cooling is something you can try but the lined on the rear coolant opening should not bee so large that they decrease the flow to a point where you get hot spots.

The Chevy 4.3L uses 4 corner cooling built into the manifold.

[95SleeperAcheiva]

So in theory, if you say cut off the water pump housing, eliminate the by-pass tube over the intake and back to the thermostat area, run an electric water pump off the lower hose again, plumb direct through the timing cover back into the block, and not turn around the intake, you should still have efficient cooling for track only use?