The Stovebolt Site Forums The Shop Area Engine Shop which edelbrock 500 vacuum port??

hey carb guys

which vacuum port do i run the distributor hose to on an ededbrock
carb. someone mentioned to me one was full vacuum all the time and the other was ?
so
if looking at that side of the carb do I run the hose to the left or right bib??
http://performanceparts.com/performance_parts_images/edelbrock_1404.jpg
or is someone pulling my leg here by telling me this??

One is full manifold vacuum & the other is called ported vacuum. The ported vacumm has no vacuum at idle. Most of the time its best to use full vacuum for the vacuum advance, but sometimes the ported works better. If it surges & idles rough at idle the ported may work better. If its an auto trans. & it clunks or lurches when you put it in drive or reverse sometimes the ported will work better after setting the idle speed down. Its a matter of experimentation.

+1 Wrenchbender. I run Holleys and there is a Timed Port and a full Vacuum port (Lowest port on the carb at the base) I was having trouble with starting and long warm ups. Drag Racer friend suggested going to full vacuum port for vacuum advance.

Tried it on a 383 stroker and a 400 poncho. Easy starts and doens'nt seem to hurt performance. I have heard that doing this will acutally retard timing at higher RPM's. Have not noticed this as if yet. Some tuning will be required if you do this,

Ok Gents,
I just watched the Official Edelbrock CD that came with my carb again & here is what the Ol Vic's Technician has to say on the procedure.
looking at the carb from the front,on the left is a slightly higher port than on the right, this higher port is "ported or timed" vacume as this port is (above the throttle plate),the Tech says this port is to be hooked up to the vacume advance on the dist.
the lower port on the right is manifold vacume (below the throttle plate)and is used for the modulator valve on an auto tranny,if ya runnin a standard tranny this port needs to be blocked off.
And of course the large port in the center goes to the PCV valve
Hope this helps,
Tim

on my #1406 edelbrock 600 c.f.m., my distributor vacuum advance is hooked to the left port.
my right port is plugged off, and i get my trans vacuum from a port in the intake between the carb and distributor.
power brake hose to booster i get from the back of the carb.
hope this helps.

leonard

The videos at edelbrock are very informative. Spent a good while watching them on my other computer (of course I can't view them with this $##%^ Apple computer!)

I can't view them with this wonderful Apple

me either :mad:
oh well i email edelbrock about the mac issue in viewing..............

thanks guys, all of you have good answers and that's just what i needed. so w/ a 50/50 chance i flubbed it.. duh . but geo you may be right so i'll leave mthat option open. i'll go take care of this right now, another exchuse to see the shop.

cheers

i emailed edelbrock that their instructional video was not comparable/viewable w/ my mcintosh computer. they sent me a CD in the mail.

those guys are really good at customer service.