Visit The Dirt Forum for More Information

Author Topic:   HEI : advance or not?
Dirt Full Roller

Total posts: 61
posted January 11, 2002 11:52 PM
I run HEI ignition on a SBC. I have always
welded the advance solid. I borrowed a
Performance Dist from a friend that has
the mechanical advance in it. I finally
got the timing set and the car runs fine.
My question is Which way is better and why?
Also, when should the advance kick in and why? Thanks in advance.

Dirt Maniac

Total posts: 174
posted January 15, 2002 07:07 AM
We have been very successful running the advance and I like the fact that we have no hassels firing the car up. I remember not long ago a racer who lost a potential win when he couldn't refire after shutting down under a red flag for a lengthy rollover clean up, while leading and running great. I send a stock HEI dist. to a guy with a machine and he sets the full advance (35 degrees) to come in at or by 3000 rpm.

Dirt Forum Racer

Total posts: 77
posted January 20, 2002 06:02 PM
I been wondering the samething.
One of the other crews said a spring
came off theres and did alot of damage
because of it.
I see that PAW sales a lock out kit
so you dont have to weld it.
when you welded yours, did you have any
problems with starting?

Dirt Roller

Total posts: 17
posted January 23, 2002 02:21 AM
You don't want to weld out your advance. While your actually racing it makes no difference whatsoever as long as you have your timing curve set correctly. Like Rover said, have your mechanical advance give you about 25 -28 degrees by 3000 RPM, AND NO MORE PAST 3000. Take it to a quality shop that can curve it for you and make sure they test and verify that the advance is done by 3000 RPM. This way when racing you will always have full advance in your racing RPM range, but the motor will still start easily and save your battery. Idle at 10 - 14 degrees to give you what you want at 3000. ( 35 - 42 degrees)

Dirt Full Roller

Total posts: 61
posted January 25, 2002 12:52 AM
YAZ, at times I did have starting problems.
This engine was esp. hard to start at first.
( 290 psi of compression might have something to do with that.) Previous engines
had different compression and cam combos and
started OK. I think I am going to stick with
the mechanical adavance. Thanx for the replies.

Dirt Full Roller

Total posts: 51
posted January 25, 2002 05:52 PM
I basically agree with 3Xracing. You want a mechanical advance to assist in starting and a smooth transition from idle but one that fully advances by 2800 or 3000 rpm.

Back to the Archives