Threaded Hole In Inlet Manifold?

[steve_tm]

Real quick one

 

There is a threaded hole in the top of manifolds of some carbys if not all of them, including the redline one i jst got.

 

i'm guessing this is for a pressure line going to a guage of some kind would i be correct in saying? if not for a heat probe) (although i would of thought something like that would of been tapped into a cylinder)

 

i've searched photos of other guys car engines, and some of them have a black rubber line running from this hole, some of them plugged!

 

jst after some clarification

 

thanks in advance

cheers

 

Steve

 

(sorry for all th shit spelling)

[kangaroosa]

Vacuum line for the brake booster.

Alternatively, it can be used for the vacuum advance for your distributor.

[Felix]

Vacuum line for the brake booster.

Alternatively, it can be used for the vacuum advance for your distributor.

 

Yep. Keep in mind that using manifold vacuum for dizzy advance is different to the more normal ported vacuum which connects directly to a carb.

 

Manifold vacuum gives you full vacuum advance at idle. It is great for smoothing out the idle of a big cam.

Edited July 15, 2009 by Felix

[steve_tm]

cheers for th reply

 

guess i was pretty wrong, haha

 

thanks again