Performance HEI Distributor question.
Race Director
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Op, great outcome! Love the thought process and research, I think you landed in a great place.
I used to be a diehard carb guy, even though I am an educated EE from high tech. I can tune a Holley with my eyes closed, never really cared for the Carter/Edelbrock carbs. That said, I tried my first EFI conversion about 15 years ago (Very Cool Parts stack injection) and never looked back. Since then, I’ve installed over a dozen EFI system and I prefer the Sniper. My ‘69 has a FAST EZ EFI that lacks spark control, but my ‘64 has a full blown Sniper with the works. I’m a convert and now a diehard EFI guy.
I used to be a diehard carb guy, even though I am an educated EE from high tech. I can tune a Holley with my eyes closed, never really cared for the Carter/Edelbrock carbs. That said, I tried my first EFI conversion about 15 years ago (Very Cool Parts stack injection) and never looked back. Since then, I’ve installed over a dozen EFI system and I prefer the Sniper. My ‘69 has a FAST EZ EFI that lacks spark control, but my ‘64 has a full blown Sniper with the works. I’m a convert and now a diehard EFI guy.
Drifting
Joined: Oct 2020
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From: Wisconsin
Just to add a bit more confusion to the discussion, the Chevrolet Performance crate motor in mine recommends the vacuum advance be disconnected (permanently), with 32 degrees all in by 3,000rpm.
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Cruise-In VIII Veteran
That's a new one. vacuum advance is put in for very good reasons. not the least of which is to keep the engine running cool on the Highway. Very, very important in these cars.
Had a 1976 L-82, 4-sp
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From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Melting Slicks
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Hi guys, once again thanks much for all the expert advice. thought I'd let you all know what I came up with. of course in addition to this thread, a bit over 40 years experience as a professional mechanic and reading everything I could find on the subject. All played into my fix.
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Still raining so I'll have to wait for dry roads to really test it. But I'm feeling confident.
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Still raining so I'll have to wait for dry roads to really test it. But I'm feeling confident.
Thread Starter
Race Director
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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Cruise-In VIII Veteran
Oh I don't know about that. something Cliff said really made a difference. I have worked on Harleys all my life. On the old Harleys that had centrifugal advance mec's. The oval slots in the base plate where the stops for idle and total advance.
on the GM distributor, the oval slots will alow the weight arms to go past the "Flat of the arm, flat on the football position". I couldn't figure out how to get it to the end of those oval slots. Thinking it was supposed to based on my experience with Harleys. So yes. I did get help, pointed in the right direction from advice on here.
on the GM distributor, the oval slots will alow the weight arms to go past the "Flat of the arm, flat on the football position". I couldn't figure out how to get it to the end of those oval slots. Thinking it was supposed to based on my experience with Harleys. So yes. I did get help, pointed in the right direction from advice on here.
Dr. Detroit
Joined: Mar 2012
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From: New Braunfels Texas
The 32 degree number maybe correct if it has Vortec heads......but the vacuum advance is a benefit and should always be implemented.
Jebby
Had a 1976 L-82, 4-sp
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From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
I believe those engines are sold for "off road use only". So if its meant for racing, why would one use a vacuum advance? A friend of mine put in a GM performance 427 into his Cobra kit car. The instructions said the same as noted above and also said for off road use only.
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Drifting
Joined: Oct 2020
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From: Wisconsin
8.0:1 compression.
76cc 1.94/1.60 heads
Cam is .450I/.460E, 222 dur, 114° centerline.
Dr. Detroit
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From: New Braunfels Texas
Drifting
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From: Wabasha Mn
Hope he's got some good gears to go with that L82 cam! My 76 L82 3.36 gear with T400 was a real dog. Later went to a Isky 264 Mega.... much better low and mid range punch! 214 214 .450 lift 108 lsa!