Factory hei distributor and coil

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txaggie

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Howdy all,

My distributor and power steering pump are the last original things on my old 85 build. Is there any merit to a high performance distributor and coil? Or should I refresh the factory gm coil (new ac Delco coil, cap, and rotor)?
 

Radiohead

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If it works, run it. You're not going to pick up 3 seconds in the ¼ mile changing to a fancy billet distributor with outboard electronics, but you might look cooler at the hoods up parking.

But I'm a cheap, grumpy old bastid like that....
 

Ricko1966

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And a universal hei is not tailored for your car so unless you are going to spend the time ,evaluating,changing,weights,springs,vacuum rate,and vacuum degrees you aren't doing yourself any favors. You could actually end up with less than you have now. And many aftermarket parts don't have the same life expectancy of original parts.
 

txaggie

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And a universal hei is not tailored for your car so unless you are going to spend the time ,evaluating,changing,weights,springs,vacuum rate,and vacuum degrees you aren't doing yourself any favors. You could actually end up with less than you have now. And many aftermarket parts don't have the same life expectancy of original parts.
Sounds good. I’ll just get a new ac Delco coil, rotor, cap and make it new.
 

Turbo4whl

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Sounds good. I’ll just get a new ac Delco coil, rotor, cap and make it new.
Put the cap and rotor on. Save the coil in the glove box. Even the new Delco coils are made overseas. Unless you see physical damage, ie overheat discolored or crud melting out, the old coil is better.
 

txaggie

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Put the cap and rotor on. Save the coil in the glove box. Even the new Delco coils are made overseas. Unless you see physical damage, ie overheat discolored or crud melting out, the old coil is better.
Sounds good. I’ll just go cap and rotor. Coil looks perfect and this was a garage kept truck it’s entire life.
 

txaggie

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Sounds good. I’ll just go cap and rotor. Coil looks perfect and this was a garage kept truck it’s entire life.
Other caveat to this is I’m excited to see how the sniper setup works with this old coil.
 

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In another thread you said you were using a Howard’s hydraulic roller cam, what’s the peak rpm? An HEI distributor is a fine piece but if you’re hitting higher rpm’s you may want something a little better.
 

txaggie

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In another thread you said you were using a Howard’s hydraulic roller cam, what’s the peak rpm? An HEI distributor is a fine piece but if you’re hitting higher rpm’s you may want something a little better.
It’s a low end cam. Pocket rpm is 1400-4900.
 

73cheyenne

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You might want to carry a spare HEI control module too. If it quits you're not going anywhere. I had one quit a long time ago.
 

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What 73cheynne said but take the small tube of grease that came with it too. I think the two most common thing that brought Cs and Ks into our shop on a hook were control modules and the white colored rotors. Not sure what GM was doing to the white rotors, but they were a very common fail. If you put a control module on without putting grease on the bottom of it, I can almost promise it will fail because of heat.
 

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It's not grease, it's heat sink paste like a computer processor uses,and genuine GM modules as well as the premium brand NAPA modules have a very low failure rate,they also are the only modules I'm aware of that vary dwell to optimize coil saturation and also make the coils life easier and longer.
 

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Howdy all,

My distributor and power steering pump are the last original things on my old 85 build. Is there any merit to a high performance distributor and coil? Or should I refresh the factory gm coil (new ac Delco coil, cap, and rotor)?
The GM HEI is actually an excellent ignition system, and, since it came from the factory on your truck, it is tailored specifically for your engine. Aftermarket units may not be. Also, they often become obsolete - can't get service parts any more. Keep it stock.

J. B.
 

JBswth

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Howdy all,

My distributor and power steering pump are the last original things on my old 85 build. Is there any merit to a high performance distributor and coil? Or should I refresh the factory gm coil (new ac Delco coil, cap, and rotor)?
Also, while you have the rotor off, try to wiggle the distributor shaft sideways. There shouldn't be any play. If there is, then you have to either get a new one for your truck or replace the bushings in your present one.

J. B.
 

dhartman

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6
Other caveat to this is I’m excited to see how the sniper setup works with this old coil.
So before we tore down for the ground up complete resto, we had the standard HEI coil and distributor on our small bock 350. Also had the sniper carb, it preformed fabulously. Never had a single issues. Turn the 1980 in to a turn key like the 90 and up trucks ran amazing.
 

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