Vacuum advance

[sublimegtx]

:icon_scratch: After I got my car I noticed that the vaccum advance from the distributor has no hose connected. The intake is plugged. I was told people do this for racing. Is this a good thing or not? The car is a "driver" for me. Someday I will probably take it to the track. Should I reconnect it? Thanks.

 

[moparmarks]

Well it needs some kinda of advance, either vaccum or mech. I put a timing light on it a see what kind of advance it has.

 

[Meep-Meep]

For a street driver, and even the occasional racer, definitely run the vac advance. I like to hook it to the ported port on the carb. This is the port that produces a vacuum signal just as you tip in (open the primaries) but nothing at idle and nothing at or near WOT.

Set the distributor up with a performance curve, meaning a little faster than stock, and have it all in at around 2500 RPM. Max advance for the basic MoPar V8 should not exceed 38 degrees. The vac advance should add about 8-10 degrees at the max ported vac signal, and that should equate to a light load "barely in the throttle" cruise.

 

[Mopars & Missiles]

.......definitely run the vac advance......

Absolutely agree :iamwithstupid:

 

[Mopars & Missiles]

Bigger graph....

 

[mopar367]

It depends if the previous owner swapped the mechanical advance springs in the bottom of the distributor. On my 360 I run with just the two light springs for the mechanical advance, and a plugged vacuum advance. It runs better I find. Also If this has been done to your distributor it will definitely ping under load with the vacuum advance attached.

 

[moparmarks]

It depends if the previous owner swapped the mechanical advance springs in the bottom of the distributor. On my 360 I run with just the two light springs for the mechanical advance, and a plugged vacuum advance. It runs better I find. Also If this has been done to your distributor it will definitely ping under load with the vacuum advance attached.

Thats what I was thinking. I'd throw a timing light on it and see what kind of, if any, advance it has. If none or little advance then I check it see if the diapham [spl?] is good. If so then follow Meep's instructions.

 

[Meep-Meep]

If the springs are too light the timing will be erratic or may be all in at idle.

 

[sublimegtx]

:icon_scratch: After I got my car I noticed that the vaccum advance from the distributor has no hose connected. The intake is plugged. I was told people do this for racing. Is this a good thing or not? The car is a "driver" for me. Someday I will probably take it to the track. Should I reconnect it? Thanks.

The car seems to run fine. Weather I'm running open exhaust, half capped, or capped cutouts. No unusual noises and plenty of giddy up. Idles like a car with a cam. I haven't pushed it towards any type of top end. I'll look into it more as time allows. Some have told me if there dosen't seem to be a problem just leave it because it may be set up fine.