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I installed a Hei on my ‘65 back in 2010( it didn’t have tach capabilities back then- disconnected). The newer version today has a tachometer connection. Do you think it’s time to upgrade?
Chevy HEI distributors had a tach connection in 1975 when they began to install them on all the new cars. I wonder what distributor you have that doesn't have the terminal?
I think the OP is saying he has and likes a HEI, but he can't connect his tach cable to it. Now he wants to purchase and install a converted HEI with the cable connection. They are available in the aftermarket for $80-$120. Correct me if I'm wrong. Dennis
They sell on Ebay for 125 or more for a billet one with tach drive. I have 3 one on a boat. They are great. I do like to put a better coil on them but it's really not necessary
Had one fail on a new 83 Buick J car wagon on a cold November Chicago area evening rush, left lane of a 4 lane artery (Dempster Ave). With new car smell still left it began pinging and bucking until stalling and failing to restart until cold again. Had to tow it. Dealer didn't suspect it, couldn't get it to "do it for them." After it began doing it again I just made it to the dealer. They left it running the next morning for an hour or two in the back until it stalled. Then they replaced the module. Yeah, if I had HEI or anything beyond breaker points I'd have a spare in the car. As it is I have a K66 board for my L78 on the shelf at the ready.
I have had both a HEI with a cable driven tach and an electric tach in my car. I much prefer the electronic tach, not that expensive and it doesn't bounce around. Very steady needle.
One good thing about HEI is when the module fails any auto parts store will have it in stock and for cheap and you will be back on the road quick
Not "if".... but "when." I had HEI on my 66 for about 4 years. Had to carry 2-3 modules in the glove box every time I'd take a road trip in the Summer. Temps go over 100 degrees.... I'd cook those things like crazy. Got to where I could change one out with the heat paste and everything in about 4 minutes. Eventually rebuilt my original distributor myself.... installed the Pertronix and never looked back.
Have had my 75 with the factory HEI for close to 50 years now, i do carry a spare module tho, no problems.
The 75 does have the tack built into it, and yes mine hasn't worked in 20 some odd years.
Not "if".... but "when." I had HEI on my 66 for about 4 years. Had to carry 2-3 modules in the glove box every time I'd take a road trip in the Summer. Temps go over 100 degrees.... I'd cook those things like crazy. Got to where I could change one out with the heat paste and everything in about 4 minutes. Eventually rebuilt my original distributor myself.... installed the Pertronix and never looked back.
I have had two different experiences with HEI modules. A 78 Chevy truck of mine blew three modules. Once at highway speed, once just wouldn't start, the other time I just drove a hundred yards, turned it off and it wouldn't restart. Other HEIs never a problem, my C4 has 200K on its original module. (I do carry a spare)
The avitar car had a cheap Chinese tach drive HEI for two years in the Texas heat, all good, but again I carried a spare.
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Originally Posted by KENS78SILVERANNIV
Not "if".... but "when." I had HEI on my 66 for about 4 years. Had to carry 2-3 modules in the glove box every time I'd take a road trip in the Summer. Temps go over 100 degrees.... I'd cook those things like crazy. Got to where I could change one out with the heat paste and everything in about 4 minutes. Eventually rebuilt my original distributor myself.... installed the Pertronix and never looked back.
My factory installed module lasted 44 years and about 76k...
When I replaced it NAPA had two modules....one foreign made & a U.S. made Echlin that cost about twice as much.
No problems since with the Echlin..
They sell on Ebay for 125 or more for a billet one with tach drive. I have 3 one on a boat. They are great. I do like to put a better coil on them but it's really not necessary
i also have HEI , but i read that the coil and module should match.... perhaps be carefull with just putting a higher voltage coil in there without changing also to a matching module ?
Not "if".... but "when." I had HEI on my 66 for about 4 years. Had to carry 2-3 modules in the glove box every time I'd take a road trip in the Summer. Temps go over 100 degrees.... I'd cook those things like crazy. Got to where I could change one out with the heat paste and everything in about 4 minutes. Eventually rebuilt my original distributor myself.... installed the Pertronix and never looked back.
Pertronix stuff is realiy good. Running their module and 60kV coil. Definitely changed my mind that module upgrades are just gimmicks.
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HEI reliability
Dennis
