Open or closed rear water jacket

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amani260

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So if you have a tbi swapped to carb motor, do the rear water jackets need to be open or closed? Wondering which gaskets to get.
 

bucket

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Where are your heater hoses plumbed to? If they go to the front of the intake and the water pump or radiator, then the rear port doesn't need to be open.

Most gaskets aren't side-specific so the rear ports are usually open. But many intakes don't have a rear coolant passage, so it doesn't really matter anyway.
 

Bextreme04

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Right, the gaskets won't matter but the intake will. You will need to get the gaskets to match your heads... since TBI, Vortec, or standard SBC have different bolt patterns. I've never seen intake gaskets that had a closed rear coolant passage, since they are not side specific.
 

amani260

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Been looking online at different intakes, looks like some have the water jacket in the front and back and some have the back closed off, just curious what the reasoning is.
 

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