Does HEI distributor have mechanical advance?
The amount of mechanical advance in a GM HEI distributor varies by application. The amount of mechanical advance is controlled mainly by the shape of the cam in the center of the weights, and to a lesser degree by the shape of the weights themselves.
Are there adjustable canisters for the HEI vacuum?
In the case of the HEI, you can actually purchase an adjustable vacuum advance canister that will allow you to custom-tune the amount of timing advance. For example, Pertronix offers an adjustable vacuum advance canister that bolts in place of the stock canister.
What kind of intake does a vacuum advance have?
Right now the engine has an Edelbrock Performer intake, a 600 cfm Holley four barrel carb, and an HEI distributor. What kind of timing should I be running and should I disconnect the vacuum advance? Jeff Smith: You’ve addressed several issues, but they are all related to ignition timing.
When do you remove the vacuum advance in WOT?
But at WOT, the vacuum drops to near zero and vacuum advance is removed and the total timing then is established by the initial plus the mechanical advance. So there are significant advantages to retaining the vacuum advance on your distributor.
Why do you need a distributor with vacuum advance?
So based on this, you can see that having a curve in the distributor along with vacuum advance is a good thing as it reduces low-speed timing where the engine might detonate with too much timing but it can also benefit from more timing at part throttle than what is required at wide open throttle.
Where does the HEI hook up to the VAC port?
Hook your HEI up to the ported (part-time) vac port on the pass side front metering block port. No vac at idle, so you can set your initial timing and idle speed without any vac intterference. On this port, you only get vac advance when you hit the gas.
Where should I hook up the VAC advance?
GM spenty a lot of money making HEI’s and V-8’s work well on vac advance and no idiot at Summit making $10/hr is going to be able to make your car run better. Thats where i was gonna run the dist. was on the passenger side of car, now where should i hook up the tranny to get the most vac?
Do you need to run vacuum advance at idle?
Vacuum advance tuning is very combination-specific. If that big block is a low compression engine, you’ll probably want to run vacuum advance. Low cylinder pressure engines typically like lots of advance at idle and light throttle to make them responsive.
Do you need a HEI distributor for a street fire?
The Street Fire HEI Distributor is not intended for extreme rpm or racing applications. In these applications, the MSD Ignition Pro-Billet HEI Distributor, PN 8365, is required. C.A.R.B. EO # D-40-39 For use on Chevy small block 350 engines, HEI, Red jacket. Upgraded to a 1 Year Warranty.