Need help converting to HEI.

I've got a '72 SB 350 in my '58 Chevy pickup. What is involved in switching to a GM HEI distributor as far as wiring? Is the coil integral in an HEI system? How is it wired into my truck with my current system? Is there just a single wire? Would I continue to use the factory ignition resister when I hook up an HEI?

Sorry, I know that's a lot of questions. I've been considering making the switch (space permitting) and when it comes to electricity, I'm in the dark (pun intended).

I don't want to go Pertronix as it doesn't seem to be a true high-energy electronic system. Rather it's just a replacement for the points, I believe?

As always, any help is appreciated.

going to hei is easy , you dont need your resistor . all you need is room for the dist itself and full 12 vlt power to the distibutor. there is a tach connection also right on the dist to run the tach off.

oh yeah the coil and everything is in the dist you will need new wires too as the hei has different ends on it.

Thanks! I appreciate the help! It's so nice to be able to come here and have all my questions answered.

My 73 Z-28 easily converted with no problems. Definitely do it.

one small detail for ya. The HEI distributor needs at least 12 GA wire. One way to accomodate this, is route the points wire to a relay, and have the relay switch a 12 GA wire feeding the HEI. You can take the switched wire straight from the battery, but it would be a much better idea to add an inline fuse ( 20 A ).

I have a question on this guys and not trying to take over the thread either. But while we are on the subject.... I just got my MSD upgrade HEI kit today, they Tune Up one. Anyways the Module will not hook up. On one side of the module you have the wires that hook up the the cap and coil, that all is fine but the other side has two prongs. This is my problem, my old one had THREE prongs not two and so the wires going into the dissy to those prongs have the female piece with 3 small prongs and the 2 big prongs on the module wont go into it....
Any idea why this is and how to fix it? I need to have this problem solved by tomarrow
Oh also the MSD kit is nice because the one I got has a rev limiter on it which they just started doing the guy said because he said they used to not have them in this kit.
Thanks a lot for any help and yeah upgrading to HEI is nice!

fmx, sounds like to me you have the wrong module for your dist. there are all kinds of modules for the hei dist. 4 pin, 5 pin, and 7 pin that i know of. :HMMM:

FMX,in answer to your question,I believe the module you need
is the 7 pin. 'Cause GM had a limiter after a fashion w/ their
brain boxes in factory vehicles. Old Gold, in case you wondered
the Mallory coil(s) are good for the HEI. Same same, Pertronix,
even Proform which is low buck (but Gary at American Speed in
Colorado Springs,CO will use a Proform in his drag car)I named
the above 'cause their output is higher than say Accel or even
MSD coils. Like modules same same, have heard good things
about Pertonix modules. Like, MSD's module replacement,also,but
is overkill unless you'll spin to 9,000 grand.Also Mallory coils are
purpose built 1 for up to idle to 5,500r's,e.t.c.And all above fit in the stock location for HEI coils. Hope this helps.

Man... Well when they say 4 pin or 7 does that mean the 4 pins on the outside of the cap? That is what I thought.... I am about to call MSD here in the next 30 minutes so any help between now and then will be helpful.
Thanks.

If you switch to a two wire pickup coil it will plug right in

Thanks for all the great info. I ordered a new HEI distributor on e-bay. Electrical stuff is my weakest point when it comes to cars, but hopefully I'll be able to figure out the installation. It doesn't sound too bad. Where can I find a 12-volt relay? At the parts store or?

Thanks again.

Bosch relays can be purchased at most any parts store, almost all late model cars have a bank of them under the hood,and they even have a wiring diagram right on the case to show you how to hook them up.

Quote:

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Originally posted by FMXhellraiser
Man... Well when they say 4 pin or 7 does that mean the 4 pins on the outside of the cap? That is what I thought.... I am about to call MSD here in the next 30 minutes so any help between now and then will be helpful.
Thanks.

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thats the # of pins thats coming out of the module. the end that plugs into the pick up should have 2 pins and on the other end it may have 2,3, or 5 pins. you sure they didnt send a 2 wire pig tail with the module? sounds like you are trying to put a 4 pin module in place of a 5 pin module and you cant do that without changing the out going pig tail.

he is saying his has 5 pins. i think he has a 3 wire pig tail that he is missing that should have come with the new module.

Ok well I figured it out. Wrong module. I called the speed shop and he asked me how many outlets the female section of the wires have and I said 3 and the old module has 3 smaller probes. He said I have the wrong one then. He even asked me if it was a 4 pin. I looked and though he meant pin for the cap (duh) and tild him yes. He said don't worry about it and to bring the old one back and he will give me the right one on Monday. The one I am getting (the right one) doesn't have a rev limiter on it but I don't think that is needed anyways. Denny, see on the right side of that pic? That connector there? Well I have one set of wires with 3 prongs going into that one that is light blue in the pic there and then that connecter into the module. It's like 2 connectors together then into the module. But anyways, I really appreciate the help guys. I am glad I found out what it was. I have been spending a few hours getting these plugs and wires on and the wires are a pain in the tail. I tried putting them over the valve covers but I just can't find a way to get them nice over it instead of all over the place and then I tried under the manifold but they are WAY too close to the manifold. I need to just find some pictures of some 305 and 350s and see how they run their wires. I dont have any wire connectors or seperators so that is out of the question for now until I have money to buy some nice ones. I actually love the Billet Specialties one that mounts on the valve cover and has the ball milled on top and the wires are ran under the plate. Looks real clean.

Hey hellraiser, do you have headers ,rams horn.or under slung style manifolds? you can make nice wire separaters with just zip ties,one looped around the wires be it 2,3 or 4and then one around the first loop between each wire,then tighten up the loops

I have the ugly stock manifolds right now with the smog pump and all the wires and hoses comming out of them. I am going to just go ahead and save to get new manifolds, carb, headers and then the billet specialties or some kind of wire seperators. I will use the trick you said halftanked thanks! I am going to rip all this wire and crap out. The guy at the speed shop said he knows a few guys that will just pass the smog test for me and I can just go ahead and buy NON EGR manifold, carb and take the cats off. Only thing is when I go to sell the truck if I will have a problem selling it. I will keep all the stock stuff though.
Denny, why is the one I have so bad? Here is what it has... On the connector up top it has a green wire, on the connector there where green goes in it has a letter H, then a yellow on the letter L and then black wire going to a D....

Denny I will get a picture tomarrow. I will post it tomarrow afternoon. I am actually about to have a party at my house right now and going to have tons of people over so when it's all over I will take a picture and post it tomarrow. I am sorry for asking a million questions the passed few weeks but I don't know non of this stuff yet and learning as I go. I have already learned a ton of stuff doing the engine and all on my 302 and now need to learn all about these 305's and 350's. This motor is a pain to work on, everything is hard to get to. My Ford is so much easier because it's so plain and hardly any wiring heh.