4.9l Performance Question

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Dec 2, 2011 | 11:32 AM

Mikey Cash

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4.9l Performance Question

I'm looking at upgrading my 1983 4.9L/300 by adding 89300 Headers, OFY 6019 intake manifold and a Edelbrock 1403 4 barrel carb. The distributer will get its vacuum from the carb but with the removal of the stock intake manifold where does the vacuum come from for the brake booster and the climate control?

Dec 2, 2011 | 11:37 AM

lavatan

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From: Rock Valley, IA

I believe the brake booster goes to a tree in the intake manifold and the climate control goes to a ball or canister near the fender.

Dec 2, 2011 | 11:43 AM

Franklin2

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From: Virginia

Most aftermarket intakes have threaded holes for this purpose. You can go buy a fitting with threads on one end and a hose barb on the other to hook the booster to. The carb will have some ports also that you can use, but the booster usually goes straight to the intake.

Dec 8, 2011 | 12:54 AM

paul

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The distributor needs a ported vacuum source from a port above the throttle plate, and not direct manifold vacuum.

Dec 8, 2011 | 07:33 AM

SideWinder4.9l

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From: Eastern Ky

Aside from a cam, suited to your needs, about the single most powerful ugrade, is a port and polish of the head.....With a 3 angle valve job w/ 30 degree back cuts....

Otherwise...Gearing makes a TON of difference with a 300...