HEI Dist Upgrades?
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,743
Likes: 37
From: Stockton Ca
HEI Dist Upgrades?
Forum: My 74 has a basic HEI Dist. I need to dial in 19* to get 32* total.
I need to know who I can sent my Dist so I can get more initial advance.
Do I need to go MSD of some kind?
TIA
R
I need to know who I can sent my Dist so I can get more initial advance.
Do I need to go MSD of some kind?
TIA
R
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Or, you can do it yourself without buying another dist'r. It worked for me following this article:
http://www.crankshaftcoalition.com/w...nition_advance
http://www.crankshaftcoalition.com/w...nition_advance
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
Or, you can do it yourself without buying another dist'r. It worked for me following this article:
http://www.crankshaftcoalition.com/w...nition_advance
http://www.crankshaftcoalition.com/w...nition_advance
Burning Brakes
Joined: May 2014
Posts: 884
Likes: 128
From: Rhine Georgia
12 degrees initial and 34 total with 12 degree vacuum advance can with full manifold vacuum. This gave me 24 degrees of timing at idle.
for full manifold vacuum
Le Mans Master
Joined: Dec 2006
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Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
Yes, but first assure that at 3000, the flyweights are at their end stop, otherwise you will go over 52 total including vacuum.
If the flyweights are not at their end stop at 3000, different springs need to be installed.
Rgds Günther
Set it at 36* at 3000rpm, and try that setting.
If the flyweights are not at their end stop at 3000, different springs need to be installed.
Rgds Günther
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,743
Likes: 37
From: Stockton Ca
I get full advance at 2800.
Problem is I need more than the 13* mechanical advance.
I have to start at 19* initial and 13* mechanical = 32*
My engine likes 32* says the dyno.
What are my options if any?
TIA
R
Problem is I need more than the 13* mechanical advance.
I have to start at 19* initial and 13* mechanical = 32*
My engine likes 32* says the dyno.
What are my options if any?
TIA
R
Race Director
Joined: May 2006
Posts: 18,731
Likes: 2,582
Last edited by MelWff; Jan 4, 2017 at 11:01 AM.
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Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
2) Keep initial timing at 13 degrees and add idle timing via vacuum advance.
3) Get a non-HEI distributor that uses advance stop bushings.
On my motor, #2 worked great.
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
Best option, but it does cost $$$, is buy a programmable ignition setup. I eventually went this route because you can program both mech'l and vacuum advance to create whatever curve you want in just minutes! I have the Mallory Max Fire.
Safety Car
Joined: Oct 2004
Posts: 3,926
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From: Youngstown Ohio
Any good custom distributor tuner should be able to custom curve your HEI. If there are none near you, give Davis DUI a call or check out their website. I have a custom curved HEI from them done to my specs of 16º mechanical + 20° initial = 36° total @ 2600 rpm.
Last edited by C3 Stroker; Jan 5, 2017 at 01:58 AM. Reason: Added information.
Le Mans Master
Joined: Dec 2006
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Great product.
Drifting
Joined: Jun 2008
Posts: 1,565
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How does DUI limit the mechanical?
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,743
Likes: 37
From: Stockton Ca
I was checking the rebuild services and no one seems to post a price for services any more.
I'm sure they would rather sell me their product. I would rather get mine rebuilt.
That way I don't have a spare Dist that I don't need!
Anyone know how much?
I'm sure they would rather sell me their product. I would rather get mine rebuilt.
That way I don't have a spare Dist that I don't need!
Anyone know how much?
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
About $200 is fair.
Safety Car
Joined: Oct 2004
Posts: 3,926
Likes: 739
From: Youngstown Ohio
You will have to call and talk to Steve Davis at Performance Distributors, as I've been told he does not use the normal "kits", but tunes the weights and springs manually on a machine to each customer's specs. There is a local shop in my city (Performance Specialties) that does it the same way, "old school style," on a Sun machine. It seems not too many tuners curve HEI's because of the extra work and time involved, but they can be curved (even locked out) just like other distributors.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
The money you save by having a shop recurve your dist, imo, would be better spent on a programmable dist with the benefits I mentioned previously. What if a recurve is still not to your liking? No problem when you can program the curve yourself in minutes and use trial and error on your time to dial it in. For me, it was well worth the few hundred extra to have this ability.
Drifting
Joined: Jun 2008
Posts: 1,565
Likes: 111
The money you save by having a shop recurve your dist, imo, would be better spent on a programmable dist with the benefits I mentioned previously. What if a recurve is still not to your liking? No problem when you can program the curve yourself in minutes and use trial and error on your time to dial it in. For me, it was well worth the few hundred extra to have this ability.
Had a 1976 L-82, 4-sp
Joined: Mar 2011
Posts: 5,338
Likes: 1,213
From: Some days your the dog and some days your the hydrant.
Royal Canadian Navy
I agree with you. Recurving the HEI is no different than any other distributor (springs and weights). The issue is how to limit the mechanical advance to something less than approx. 22 degrees. You have to find a way to positively stop the mechanical advance plate or else the mechanism will keep advancing until it reaches the factory determined advance limit. You can use stiffer springs so that the unit never actually reaches full mechanical advance prior to engine redline, but this changes the entire curve. The only way I see to limit mechanical advance is the 'screw method' discussed above. But I'm curious how DUI does it.