Nomad78SA

I have a Performer air gap intake and a 4150 Holley carb and the secondaries cover the vacuum port. What do I do? Can I buy a low profile fitting somewhere?
I am using the big port in the back of the carb for the brake power boster and the one on the bottom in the front for the distributor vacuum advance.
I have plugged off the port on the side up toward the top of the carb. What is it for?
Thanks for any help,
Neil in Tenn


[Modified by Nomad78SA, 10:30 PM 11/11/2003]

72CoupeORG(smc)

the one on the side that you plugged is for the vacuum advance. it doesn't create vacuum until you depress the pedal a little. i use the one in the front for my vac needs. if you need the continuous vacuum for your advance(aka have overheating problems) you can just use a T fitting and split the line.

yellow 72

http://www.jegs.com/cgi-bin/ncommerc...06&prmenbr=361

rob75383

With my RPM air gap, this fitting was about twice as tall as the actual clearance between the squirter cover and the manifold.
I'm guessing that with your performer air gap, you have a little more room, but you'll probably still have to grind off some meat from the fitting to get clearance, as I had to do with my old performer.
I have my vacuum lines for the trans, air vents, and headlights teed off and fed from the front port under the primary float.
It seemed easier than plugging the original hole, and drilling and tapping a new hole in the intake just to get vacuum.

I have heard about people using manifold vacuum (big port in rear, under the float, and small port in front under the float) for their vacuum advance, but usually you want the ported vacuum (the port high on the passenger side) supplying the signal to the distributor.



[Modified by '75 383 ElkGrove, 5:18 AM 11/12/2003]

Nomad78SA

Thanks to each of you for the suggestions. Seeing how I might have to modify the bought fitting I went ahead and fabricated on of my own. The original on had 3 ports but I went to a 700R4 so 1 is no longer needed.

I took a 1/4 inch threaded dual port brass fitting and mated it to a 1/2 to 1/4 inch reducer. When just screwed in like the first one it is too tall. I placed the reducer in a lathe and turned the head off of it seeing how I could use the flat on the 2 port. Inserted the piece and tightened it on down with sealant. Presto, plenty of clearence to go under the secondary bowl. I will put it on tomorrow and post some pics.
Neil in Tenn

yellow 72

If you have the room you could run a phenolic spacer to gain a little clearance and also have some heat isolation....


[Modified by yellow 72, 11:38 AM 11/13/2003]

A C

:iagree:

I put in a 1 inch spacer....lots of room now. :D

Nomad78SA

The aircleaner stud hit the hood the first time it was closed. :eek: I may have a slight clearance issue at hand now so I will need to check clearance again to see what I have got, but I am a little gun shy now... :yesnod: I have got a drop base air cleaner now..
I try out this fitting for the time being
Neil in Tenn


[Modified by Nomad78SA, 8:25 PM 11/13/2003]