Max mechanical advance HEI
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
It varies greatly from one distruibutor to another. Some of the short-curve distributors run an 18-degree curve, while others are in the 24-26 degree range. You can't change the length of the curve with the springs.
Thread Starter
Pro
Joined: Mar 2004
Posts: 584
Likes: 0
From: Okemos MI
Thanks Lars,
That helps alot. It looks like my max is 22. I thought something was wrong or I was crazy.
I was shooting for 36 with 8 initial. never could make it happen.
I just got to 34 with 12 initial and it runs strong
Thanks again
John
That helps alot. It looks like my max is 22. I thought something was wrong or I was crazy.
I was shooting for 36 with 8 initial. never could make it happen.
I just got to 34 with 12 initial and it runs strong
Thanks again
John
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,390
From: At my Bar drinking and wrenching in Lafayette Colorado
Bump that initial up to 14 so you get 36 total - it will run even stronger. I like to shoot for initial timing in the 16 to 18 degree range, and you can get this with a short-curve distributor. You don't ever want to run less than 12 degrees intial timing in a performance engine unless you're wanting to pass an emissions test.
Racer
Joined: Jul 2007
Posts: 444
Likes: 0
From: Roselle IL
Lars,
I am going through all of this on my 427. My HEI has the 18* curve ,which leaves my idle at 18*. However, I also have a vac. adv. which adds another 12-14, putting my actual idle advance at about 32. Is this OK?
I am going through all of this on my 427. My HEI has the 18* curve ,which leaves my idle at 18*. However, I also have a vac. adv. which adds another 12-14, putting my actual idle advance at about 32. Is this OK?
