Rear intake crossover ??

[MYBAD79]

Just curious: on my old Performer manifold the rear cooling crossover passage was blocked, on my new air-gap manifold there are NPT threaded holes on each side so the two could be connected with for example 8AN SS braided hose... any advantage of doing that other than adding more 'bling' ?? Are the two sides connected when using a stock manifold ??

 

[Bee Jay]

You have the option to run hose from the two rear water outlets to the front of the manifold, either into a thermostat housing or into the front water outlets/inlets. This is suposed to help cooling. I also have an rpm air gap and will have to decide soon to either hook these rear outlets to the front, or just plug them. Anyone done this? What were your results?
Bee Jay

 

[badbirdcage]

In 86 when they started putting aluminum heads on the L98 motors in the convertibles they put a pin hole in the manifold gasket and plumbed the passenger side rear cooling port from the intake manifold to the supply line for the heater core to aid in cooling at the back of the block. Why they did only one side I don't know.

Rich:beer:

 

[mrvette]

In 86 when they started putting aluminum heads on the L98 motors in the convertibles they put a pin hole in the manifold gasket and plumbed the passenger side rear cooling port from the intake manifold to the supply line for the heater core to aid in cooling at the back of the block. Why they did only one side I don't know.

Rich:beer:

On the L98 mani's I have looked at, from F body or Y body, and aftermarket, I have seen the passage way open between banks, and noticed the 1/8 NPT fitting hole almost under the dizzy was connected to the suction side of the water pump, in the heater hose, which is what I have always followed through with even with the iron heads on this engine,......I have to assume it evens out the cooling somehow, even with the LT1 highly modded intake on the car now, it's still been done...

:beer: