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HEI upgrades?

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Old Dec 31, 2006 | 03:18 PM
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Default HEI upgrades?

Well I guess with all the million $$ behind GM, they must have sorted the best ignition for their cars with the limits placed upon them...

So, I want to keep my stock HEI dizzy but is there any thing I could add to bring it screaming into the 21st Century?

Have read about MSD boxes, high output coils etc...I see MSD do an Ultimate HEI upgrade kit.

Any recommendations?
TIA.

Last edited by jotto; Dec 31, 2006 at 03:26 PM.
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Old Dec 31, 2006 | 04:26 PM
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I'm tired of not getting adv w/HEI. What can be done to get more than the 12*-13* in the dist?

Ricisan
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Old Dec 31, 2006 | 05:22 PM
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High output coil and newer control module and it will look stock and give you a touch more spark. Your not going to strap on 30hp with an ignition change, but it will help the ignition system effienciency a bit.
There are kits out there for advance, new cans, springs, cams, bushings etc. Summit, Jegs and a bunch of others carry them
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Old Dec 31, 2006 | 07:09 PM
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Originally Posted by SIXFOOTER
High output coil and newer control module and it will look stock and give you a touch more spark. Your not going to strap on 30hp with an ignition change, but it will help the ignition system effienciency a bit.
There are kits out there for advance, new cans, springs, cams, bushings etc. Summit, Jegs and a bunch of others carry them


Biggest problem with stock is the oem coil. Changing it alone can give you good spark to 7k. Accell & MSD have super coils that will give you up to 42000 volts and increase spark energey by 50%.
All oem v8 hei dist were made with 20° advance at the crank built in +/-1°. So for a total max of 38° set the initial to 18°.
If you want more you'll have to change the springs, weights and plate.

The stock GM modules have a variable dwell circuit built in that a lot of the aftermarket ones don't. This keeps the coil from overstaturating at lower rpm and promotes longer coil life.

Upgrading your stock hei is more than enough for most people and a lot cheaper than all the extra boxes etc.

If in the market for a replacement, here is a good distributer and they will set it up to your specs
http://65.57.252.46/gm.htm
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Old Dec 31, 2006 | 08:24 PM
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I recomend you get a good re-curve kit, end play shims, and an adjustable aftermarket vacuum canister so you can use manifold vacuum. The rest you can run stock and see how you like it.

-Mark.
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Old Jan 1, 2007 | 07:07 AM
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Originally Posted by stingr69
I recomend you get a good re-curve kit, end play shims, and an adjustable aftermarket vacuum canister so you can use manifold vacuum. The rest you can run stock and see how you like it.

-Mark.
I have some shims and a recurve kit on order. Havent got an adjustable vac can.

I know the stock HEI is good, just wanted to possibly make it better.
Was thinking of this at summit for $170



Quote : The ultimate distributor.
These Ultimate HEI kits from MSD have everything you need to turn your early model GM HEI distributor into a great performance distributor. The MSD HEI modules feature special circuitry to produce 50 percent higher coil drive currents than stock modules, resulting in higher spark energy at racing rpms. By matching the coil specifications with the modules, MSD delivers more accurate timing and dwell control. The kits also include a high-quality rotor, a durable cap with brass terminals, and even a new dust cover.
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Old Jan 1, 2007 | 10:10 AM
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Originally Posted by jotto
I have some shims and a recurve kit on order. Havent got an adjustable vac can.

I know the stock HEI is good, just wanted to possibly make it better.
Was thinking of this at summit for $170



Quote : The ultimate distributor.
These Ultimate HEI kits from MSD have everything you need to turn your early model GM HEI distributor into a great performance distributor. The MSD HEI modules feature special circuitry to produce 50 percent higher coil drive currents than stock modules, resulting in higher spark energy at racing rpms. By matching the coil specifications with the modules, MSD delivers more accurate timing and dwell control. The kits also include a high-quality rotor, a durable cap with brass terminals, and even a new dust cover.

I have read things about the HEI and the issues with stock parts and high RPM. David Vizard says he likes that particular MSD module a lot so you have to give that some weight. At the same time, GM sucessfuly sells a HD racing HEI in the power manual and LOTS of people are having sucess running near stock HEI's at the track. I was on the fence.

For my own experience I decided to try an aftermarket Pertronix Flamethrower HEI upgrade kit to see if it would increase performance. I went with the Flamethrower kit that has all the goodies in one box. Lots of stuff in there for the money. The results were mixed and less than spectacular. The car would run well at first but randomly start to misfire once in a while belching out smoke and stumbling. Not good.

After some diagnosis, I suspected the new Pertronix coil so I decided to try going back to the stock GM ignition coil and module. Now the car runs great all the way up to 6000 RPM and never stumbles. I sent the coil back to Pertronix and they sent me back "a coil" in a box. Might be them sending me a new one or it might just be my defective coil being sent back? I am not sure but I am not going to bother trying it again either.

Pertronix - The pros - realy good advance curve kit that solves the problems with the OEM smog curve. Maybe the best one out there as I have seen quite a few crappy ones and this one impressed me. Decent adjustable advance cannister that you can use with manifold vacuum if you desire. Decent cap & rotor too.

Cons - questionable electronics - I am not convinced I realy need them either. They are staying in the box for now.

I would suggest you shim and recurve first, do some driving, then come back and spend the big bucks on the MSD module/coil kit. Then you can do some back to back testing and let us know how your experience worked out. We would all benefit from some real world test results.

Some times a bazooka is more than you need to shoot some rabbits.

JMO.

-Mark.
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Old Jan 1, 2007 | 10:24 AM
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I've been running a Mallory direct replacment HEI from Summit. Tuning was easy since it came with 3 sets of springs and adjustable vac advance. After playing around with the different springs, I ultimately I settled back to the ones that were originally installed from the factory.
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Old Jan 1, 2007 | 11:26 AM
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marshrat99, do you have a part # to hand, quite a few to choose from...
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Old Jan 1, 2007 | 05:43 PM
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Circle tracks around here ... seems "DynaMod" race module from Davis is preferred ... and seems stock coil does about as well as any when paired w/ good module.
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Old Jan 1, 2007 | 11:01 PM
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Originally Posted by jotto
marshrat99, do you have a part # to hand, quite a few to choose from...
Have a look at Summit part number 8548201. The price is pretty decent for what you get.
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Old Jan 2, 2007 | 01:19 PM
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Originally Posted by jotto
I have some shims and a recurve kit on order. Havent got an adjustable vac can.

I know the stock HEI is good, just wanted to possibly make it better.
Was thinking of this at summit for $170



Quote : The ultimate distributor.
These Ultimate HEI kits from MSD have everything you need to turn your early model GM HEI distributor into a great performance distributor. The MSD HEI modules feature special circuitry to produce 50 percent higher coil drive currents than stock modules, resulting in higher spark energy at racing rpms. By matching the coil specifications with the modules, MSD delivers more accurate timing and dwell control. The kits also include a high-quality rotor, a durable cap with brass terminals, and even a new dust cover.
That's what I am using with MSD's low empendance coil bushing and a Crane's adjustable vacuum advance (which came with springs too for the mechanical advance). System helped my ZZ4 run alot better ... the recurve I think did the engine wonders. Been running it for over a year now.
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Old Jan 11, 2007 | 10:32 PM
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Old Jan 12, 2007 | 06:23 AM
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Originally Posted by jackson
Circle tracks around here ... seems "DynaMod" race module from Davis is preferred ... and seems stock coil does about as well as any when paired w/ good module.
I have the Davis Unified Ignition street/strip on my Vert...bought it that way...I hafta assume that after the dual quad install, they needed more punch on the ignition side....I've also recurved it and installed a new vac can, old one was seized....I'm very pleased with my present setup
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Old Jan 12, 2007 | 09:49 AM
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I have found through the years, the best things to do with any HEI, is number ONE, replace the sending coil under the rotor, has a plug with green or wh/yel wires into the module.....they fry out from heat and can go intermittent...ask me how I know this......second....make damn sure both of the spade terminals on the main coil in the cap, are SOLDERED to the naked wire, not just crimped.....I had one of them open up on me right at the crimp, which they do without cleaning off the formvar the wire is wound with....so there was in fact nothing rong with the coil itself....in fact I have never seen/heard of a proven bad HEI coil....but for that one defect.....the first fix means the dist has to come completely apart....may as well set the end play on the shaft also...nice and snug, about 10 mills is fine...should spin freely without any binding, gotta center that pickup coil carefully to keep the toothed wheel from hitting....there is a magnet in there, well duh.....
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Old Aug 25, 2011 | 09:51 PM
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Good thread.
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Old Aug 26, 2011 | 02:01 AM
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I buy the Whole HEI off ebay with a price anywhere from $37 TO $54.
They work perfect and come with a hot coil so you can set your plug gap at .040 and get a longer spark. Also a brass terminal cap.
Never had any trouble with them and I saved a whole lot of money.
But some people have to have that name brand to make them feel good at $175.
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Old Aug 26, 2011 | 12:51 PM
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Originally Posted by Tim H
I buy the Whole HEI off ebay with a price anywhere from $37 TO $54.
They work perfect and come with a hot coil so you can set your plug gap at .040 and get a longer spark. Also a brass terminal cap.
Never had any trouble with them and I saved a whole lot of money.
But some people have to have that name brand to make them feel good at $175.
bought this one about a month ago for 38.50 free shipping. http://cgi.ebay.com/ebaymotors/sbc-b...treme-65k-coil

Last edited by 78 silver 78; Aug 26, 2011 at 12:57 PM.
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