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Old 12-11-2007, 09:18 AM
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Tina69
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Default hei conversion

Question
Can an original 69 points distributor be converted to a HEI module setup using the original distributor to get rid of the points setup? If yes, what setup would you reccomend?
Thanks for any input.

Last edited by Tina69; 12-11-2007 at 09:20 AM. Reason: clarification
Old 12-11-2007, 09:37 AM
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houstonvett
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I have never seen an original distirbutor set up fpr a HEI conversion. HEI units have the coil in the cap and uses the big HEI cap. The original 69 distributor would have to have a lot of work done to it to make the big cap fit right. Might be better off buying a new HEI setup and just keeping your old original distributor around just in case you want to sell your car or take it back to factory stock, houstonvett
Old 12-11-2007, 09:41 AM
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lars
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Originally Posted by Tina69
Question
Can an original 69 points distributor be converted to a HEI module setup using the original distributor to get rid of the points setup? If yes, what setup would you reccomend?
Thanks for any input.
There is no need to. A properly set up stock points distributor will perform as well as - or better than - anything on the market and is very low maintenance.
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Old 12-11-2007, 10:03 AM
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69427
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I've converted my '69 distributor, my buddy's '72, and several other small cap distributors to use a VR sensor and an HEI module. The VR sensor was reasonably cheap, and I just wired that up to a four terminal HEI module attached under the chrome shielding. Bulletproof, great plug life, and zero maintenance.
Old 12-11-2007, 07:40 PM
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http://www.davessmallbodyheis.com/
Old 12-11-2007, 07:51 PM
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battjke
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I've converted mine with a Petronix unit....installs in your stock distributor in place of your points....I can now pull 6500 RPM
Old 12-11-2007, 09:44 PM
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Originally Posted by Tina69
Question
Can an original 69 points distributor be converted to a HEI module setup using the original distributor to get rid of the points setup? If yes, what setup would you reccomend?
Thanks for any input.
Just drop in an HEI distributor. It's cheap, easy, and if something breaks parts are available at any parts store.
Old 12-11-2007, 10:04 PM
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Mike Ward
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Originally Posted by battjke
I've converted mine with a Petronix unit....installs in your stock distributor in place of your points....I can now pull 6500 RPM
A distributor with a petronix unit is NOT equivalent to an HEI unit. Two different animals.
Old 12-11-2007, 11:28 PM
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Default Hei rules

Originally Posted by Mike Ward
A distributor with a petronix unit is NOT equivalent to an HEI unit. Two different animals.

Very True!! You can set up a points system as well as possible or go with any points replacement modules and yet it will not compare to a Hei unit!
Old 12-11-2007, 11:55 PM
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just go with crane or pertronix conversion, looks stock and gives better spark overall or do as lars says and keep points
Old 12-12-2007, 03:25 AM
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RunningMan373
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Originally Posted by I'm Batman
Just drop in an HEI distributor. It's cheap, easy, and if something breaks parts are available at any parts store.


Save your original stuff, run the modern.
Old 12-12-2007, 05:12 AM
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Originally Posted by houstonvett
I have never seen an original distirbutor set up fpr a HEI conversion. HEI units have the coil in the cap and uses the big HEI cap. The original 69 distributor would have to have a lot of work done to it to make the big cap fit right. Might be better off buying a new HEI setup and just keeping your old original distributor around just in case you want to sell your car or take it back to factory stock, houstonvett
There is a small-cap HEI, but you have to have a computer controlling your advance as there is no way to run a vacuum advance on it. They were used on some Camaro and Firebird V8s just before the LT1 was introduced.

Originally Posted by lars
There is no need to. A properly set up stock points distributor will perform as well as - or better than - anything on the market and is very low maintenance.
I respectfully disagree. The HEI produces a much hotter spark than the old points system.
Old 12-12-2007, 10:26 AM
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Originally Posted by I'm Batman
I respectfully disagree. The HEI produces a much hotter spark than the old points system.
Back-to-back dyno testing I did with Hot Rod Magazine on the Westech engine dyno showed absolutely no power/performance difference whatsoever between a points distributor and an HEI with identical advance curves in a mild 370-horse engine. None. That's the fact. I have the dyno sheets and numbers - you have something that shows differently..? In fact, when we added an MSD system to the points distributor, it showed a 5-horse gain over the HEI in the mid and upper rpm range.
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Old 12-12-2007, 11:00 AM
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Originally Posted by lars
Back-to-back dyno testing I did with Hot Rod Magazine on the Westech engine dyno showed absolutely no power/performance difference whatsoever between a points distributor and an HEI with identical advance curves in a mild 370-horse engine. None. That's the fact. I have the dyno sheets and numbers - you have something that shows differently..? In fact, when we added an MSD system to the points distributor, it showed a 5-horse gain over the HEI in the mid and upper rpm range.
Interesting...I've been looking around for some quantifiable data on the subject without much success so far.

At the very least, IMHO, the simplicity/lack of "tinkering" is a huge plus in the HEI's favor.
Old 12-12-2007, 11:25 AM
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Originally Posted by lars
Back-to-back dyno testing I did with Hot Rod Magazine on the Westech engine dyno showed absolutely no power/performance difference whatsoever between a points distributor and an HEI with identical advance curves in a mild 370-horse engine. None. That's the fact. I have the dyno sheets and numbers - you have something that shows differently..? In fact, when we added an MSD system to the points distributor, it showed a 5-horse gain over the HEI in the mid and upper rpm range.
To what do you attribute the HP gain with the MSD box?
Old 12-12-2007, 11:33 AM
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Originally Posted by I'm Batman



I respectfully disagree. The HEI produces a much hotter spark than the old points system.
That just enables longer time between tune-ups. That was it's original intent.
Old 12-12-2007, 12:38 PM
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Originally Posted by I'm Batman
Interesting...I've been looking around for some quantifiable data on the subject without much success so far.

At the very least, IMHO, the simplicity/lack of "tinkering" is a huge plus in the HEI's favor.
Batman -
I'm fortunate in that I've had the opportunity to do actual testing of a lot of components, both on the dyno and on test cars. Certain components will show a performance advantage under certain conditions, and not under others. For example, an HEI system will show an advantage over a stock points system if cylinder pressures are extremely high. Most street applications do not have cylinder pressures high enough to take advantage of this, and will not show an actual performance increase with the HEI alone. In fact, most HEI systems have a slower advance curve (for emissions purposes) than the old points distributors, and can actually show a performance decrease compared to a well-curved points system if the curve is not corrected. So simply swapping in an HEI is no assurance of a "performance" setup. The advance curve is more important than spark voltage on a modest performance street engine.

The HEI system was designed to assist with emissions controls. The use of the HEI on low compression engines allowed a wide plug gap to be used to assure igniting the air/fuel mixture reliably under varying conditions. The elimination of points assured that timing would never change and never need to be re-set, thus assuring reliable operation with low emissions for extended periods of time. The HEI system will produce a higher voltage at higher rpm (when dwell time is shorter) than a standard points system, and this can be effectively used in a high compression engine with high volumetric efficiency (high cylinder pressures) if the plug gap is reduiced down to about .035 - .040". A standard points system will do the same if used with a CD system such as MSD.

On modest street performance engines operating below 6500 rpm, the shape of the advance curve is much more important to performance than increasing system voltage. Paying attention to precise setup and tuning has much greater gains than swapping out components and distributors.
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Old 12-12-2007, 12:49 PM
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markdtn
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To answer the original question, use a Pertronix or similar unit in the original distributor if the only goal is to eliminate the points. If you want an HEI, you would have to get a tach-drive version to keep the original mechanical tach or a standard version and change your tach to a 75-77 electronic one-then the faces don't match (it is also possible to have the original tach converted). When you convert to HEI you also have to change or at least re-gap your spark plugs, and change plug wires.
Old 10-28-2015, 12:47 AM
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Originally Posted by 69427
I've converted my '69 distributor, my buddy's '72, and several other small cap distributors to use a VR sensor and an HEI module. The VR sensor was reasonably cheap, and I just wired that up to a four terminal HEI module attached under the chrome shielding. Bulletproof, great plug life, and zero maintenance.
I have a 'Daves HEI' distributor for my '71 350/270, that I have not yet installed.

Where/how did you attach the module to the chrome shielding box?

Thanks
Old 10-28-2015, 07:48 AM
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