VACUNM ADVANCE UNHOOKED

Posted By: Anonymous

VACUNM ADVANCE UNHOOKED - 10/06/08 12:18 AM

Just wondering what is the advantage of having the vacunm advance unhooked or isn't there any advantage.I'm seeing alot of 440's at car shows with them disconneted.

Thanks Moparts

Posted By: B9ChargerSE440

Re: VACUNM ADVANCE UNHOOKED - 10/06/08 01:12 AM

Yes i have seen that also, on my 340 i have it unplugged because if it was plugged in the rpms would sky rocket and stay there without touching the gas pedal!! I have no problems with the car so far!!

Attached picture 4731739-HemiUnderGlass.jpg

Posted By: torkrules

Re: VACUNM ADVANCE UNHOOKED - 10/06/08 01:15 AM

Quote:

Just wondering what is the advantage of having the vacunm advance unhooked or isn't there any advantage.I'm seeing alot of 440's at car shows with them disconneted.

Thanks Moparts

I'm sure you will get a lot of different answers to this and mine is....it depends. Usually when you have changed the curve so that it is quicker (lighter springs) and/or the total mechanical timing has been changed so that it is less (you then run more initial timing) most guys will omit the vacuum advance.

Guys who run street and strip will also disconnect it as it has no use at full throttle (zero vacuum). Usually at this point an aftermarket distributor like an MSD.

If you do a lot of street cruising, it's always best to try to use it as helps keep the plugs clean and you get better fuel mileage. I'm in this category. I tried to use it on mine but my engine hated it, so I'm running the older Direct Connection electronic ignition with no vacuum advance. Car runs great with this set up.

Posted By: dave571

Re: VACUNM ADVANCE UNHOOKED - 10/06/08 01:32 AM

as said, there could be a few reasons not to run it/leave it unplugged.

If the distributor has been set up with an aggresive curve, or for racing only, it would normally be unplugged. might ping under light load otherwise.

I use a delete plate to cover the hole, and still have a tab to line the cap up with, but if you didn't have that, you would likely have to put the vac pod back on, so the cap would have an index.

On most street cars, there is no real benefit to not running vac advance, BUT equally if your distributor has been set up properly it's all out performance will not be any different with the unit unplugged.

It shouldn't even affect your idle, as ported is the correct source for vac advance. It should only add timing under light cruise.