[captain42082]

holley 750 dp sitting on a wilson 4 hole 1" spacer,sitting on a tomahawk intake-i am fighting a vacuum leak? bogs when kicking in secondaries-have an open gasket on top of the intake,then spacer,then another open gasket between spacer and carb,is this right? wondering if maybe it needs a 4 hole gasket between spacer and carb??learning as i go,b easy!

[captain42082]

newbie question? the level surface of the spacer mates to the carb,gasket between?

[panhead59]

Yes that's right. Generally speaking, you need a gasket anytime there is metal to metal contact on something like that. Of course there are execptions.

[carbking]

Will leave the Holley bogging to others, but for the gaskets/spacer:

(1) Remove the carb, gaskets, and spacer.
(2) Place one of the gaskets on the top of the intake, line up the mounting bolts, and check for leaks. You need at least 1/8 inch (3/16 is better) gasket to intake mating surface all the way around.
(3) Check the gasket(s) to spacer in like manner.
(4) After draining the fuel, turn the carb upside down. Look for any passages OUTSIDE the area covered by the spacer (idle screws, vacuum passage to PCV, or distributor, or???). If you find any, check that the gasket is either cut out (to vacuum, if necessary) or covers these passages.

There are literally 100's of mounting gaskets. You have to make sure what you have seals.

A four hole under the carb would not help.

Jon.

[captain42082]

thanks for the responses!I thought maybe this was a source of a vacuum leak,going to use new gaskets when I reinstall the carb.I was second guessing myself on the 4 hole spacer,I had installed with the flat part facing up toward the carb