When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I have a 1973 corvette the HEI distributor (with a red and black wire) and the coil was the stock gm coil with a Resistor wire and the cloth sleeved wire attached . The coil was labeled “use with external resister”. during installation of a Holley sniper quadrojet I damaged the stock coil and replaced it with a msd master blaster 2. I used the the same wiring as before.
I have the sniper negative coil lead hooked up to the negative coil post but couldn’t not get rpm to register on the hand held. Or the vehicle to even act like it wanted to start.
The hand held remains at “stalled” for RPMs. I feel like the new coil is not hooked up correctly? I send the sniper back to Holley for diagnostics and they said nothing is wrong. So the problem is on my side. Does anyone have any thoughts on a way forward?
here is a link that talks about the two different coil styles.
An HEI distributor has the coil in the cap yet you posted a point style coil which would use the dual wires on the positive terminal. An HEI distributor would need a constant 12 volt source with no resistor.
So exactly what distributor do you have, a picture would help.
1973 did not have HEI.
A real HEI distributor has a TACH terminal on the cap where the RPM would be picked up.
I’ll provide a picture after work. So I have an after market HEI but the coil was still wired with the old coil. When I was installing the sniper quadrojet I broke the positive post of the coil (like the one in the photo) so I replaced it with an msd master blaster. When I did the car refused to crank. Sent the carb to Holley and they said it’s not the sniper but my wiring. I think I’m connecting the HEI incorrectly. I think with the new coil I need to source the 12v powe from the ING post in the fuse box. At least that’s what I’ve researched so far.... photos will come later...
Yes it is strange that they keep the old coil on the car when the they replaced the points with HEI. I did read that that is possible to keep the coil but isn't very efficient, Its been running with that points coil for around 10+ years now. Where I ran into problems is when I replaced the old coil with a new one this weekend. The sniper EFI is being mailed back to me now and should be in soon. When it does come I have a couple ideas to trouble shot. I have two wires coming off the distributer (black and red). I'm going to run the red wire to ING fuse box. black wire to coil neg and the yellow sniper wire to coil neg & see what happens. (I'll provide the photos this afternoon. Thanks for the help/over watch.
No I'm not going to use the sniper to control timing but I do need to have the unit attached to the neg coil post to register RMPs. But when it was last hooked up it was registering as "stalled even when cranking, not showing any rmps. Again I'm sure its due to replace the old points style coil with a new 21st century MSD style coil. But I need to figure out how to get the new coil hot.
Not a very good photo of that distributor to be certain. BUT, doesn't look like a HEI to me.
Never heard of a HEI without a coil built in to the top.
hi. Thank you for taking a look. After some research I think I have a Pertronix conversion HEI. They had it linked to the coil positive instead of 12v continuous power from fuse box.
my plan is to connect Pertronix red to ING fuse for continuous power and the black distributor wire to coil neg
hi. Thank you for taking a look. After some research I think I have a Pertronix conversion HEI. They had it linked to the coil positive instead of 12v continuous power from fuse box.
my plan is to connect Pertronix red to ING fuse for continuous power and the black distributor wire to coil neg
Stop confusing people by saying HEI, that is NOT HEI.
You have a Pertronix distributor or a conversion kit.
The red wire from the Petronix should go to the IGN post in the fuse box.
The black wire goes to the negative terminal of the coil.
The original wires coming through the firewall are not used.
Did you buy the correct coil, there is more than one MSD Blaster 2?
this aftermarket setup gets called small cap hei. https://swperformanceparts.com/produ...MaAoTREALw_wcB this IS a small cap HEI. https://www.holley.com/products/igni...saAoXxEALw_wcB the sniper can control spark advance so you do not want a vacuum-centrifugal distributor. the small cap hei is designed to be run by the ecm. and the ecm can manage your timing better than you could ever achieve with a timing light and a book on tweaking vacuum and weights. inexpensive and durable.setup. and IT knows how to retard the timing when necessary.
Last edited by derekderek; Feb 7, 2021 at 06:00 PM.
Hi Derek
this is where I’m at on getting my car back on the road
when I discovered what a Pertronix distributor was and I had one I wired it the same way you described. But the only way I could get the engine to crack was to connect the cloth wire (the one that provide 12v when cracking) to then positive side of the coil. But hat crank was only 1-2 sec of engine turn and nothing else.
So today I decided to place the old coil back on as it was before the sniper install but before I could reconnect the wires I noticed my new coil wire has a broken connector. So I didn’t test the old method but rather older a new coil wire. plus, I really want to know if my new coil is compatible with the Pertronix distributor. I hope you know and will tell me. That maybe one of my problems
I read that you can run then old stock Coil with the Pertronix distributor setup but it just runs below 12v. And hats the set up I had prior to he sniper.
So plan is to try a couple different things before I swallow my pride and send it to my mechanic my nuclear option is provide my mechanic with a new distorted an box he comes up empty on a solution. The Pertronix distributor is around 10*+ years old and it’s probably time to get a “ true” hei.
sorry for all the grammatical errors. This web site and my iPad are not getting along & I had to restart my reply a couple of times.... thanks for the help and I’m looking forward to what you have to say.
1973 corvette sniper EFI problem (Coil - spark)
