GM HEI

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Cope

Fusing with fire
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Oh GM HEI, How I hate thee... let me count the ways...


GOOD LORD I HATE THESE PILES OF GARBAGE.

Im gonna go out on a limb and say I HAVE NEVER had one work right.

Two dead out of the box from summit in a row and now one more that wont time.

The one im referring to now is not new. BUT i have seen this exact same issue in these distributors before this.

This one is 8 deg at 850 RPM and FORTY NINE AT 3,500 RPM....

im gonna look deeper at it tomorrow most likely but I already know how to fix it.

MSD probillet and 6AL. DONE. NO MORE TIMING ISSUES.


Has anyone ever had a GM HEI that worked good?

:BangHead:
 
Oh GM HEI, How I hate thee... let me count the ways...


GOOD LORD I HATE THESE PILES OF GARBAGE.

Im gonna go out on a limb and say I HAVE NEVER had one work right.

Two dead out of the box from summit in a row and now one more that wont time.

The one im referring to now is not new. BUT i have seen this exact same issue in these distributors before this.

This one is 8 deg at 850 RPM and FORTY NINE AT 3,500 RPM....

im gonna look deeper at it tomorrow most likely but I already know how to fix it.

MSD probillet and 6AL. DONE. NO MORE TIMING ISSUES.


Has anyone ever had a GM HEI that worked good?

:BangHead:
Every small block chevy i ever had to deal with. And when i repaired them it was with BWD or standard ignition parts.
I despise msd and pertronics crap. Overpriced failures.
 
The problem is likely not the HEI tech, but cheap Chinese replacement parts. I'm running a quality HEI module with my factory Mopar distributor in the Barracuda. Haven't driven it yet, though.
 
Im sure there are lots of cars running around just fine with them.

This was was running and driving "fine".....

Well it had "a little" off idle stumble and was pouring gasoline out the tail pipes but it was "driveable"....


The sex appeal of a MSD probillet is second to none in my opinion. I have installed many and worked on tuned more and they just work. (Until they stop/die completely)

Like all digital electronics, once that circuit burns out, it never comes back and some sand paper aint fixin it.


Lastly, the HEI cap... gag.. why didnt they make it larger and more ugly. I only half way go blind when I look at one..

:)
 
I have a GM HEI style big cap distributor in my 75 F250 with a 351M engine. Been there bout 6 or 7 years now. Never a hiccup. 20 initial and about 37 total. Rock solid.
 
Im sure there are lots of cars running around just fine with them.
Yeah, like EVERY SINGLE GM product from 74 to about 85. Think about that a minute. EVERY SINGLE GM PRODUCT. We're talkin HUNDREDS of MILLIONS of vehicles. So to say it's the GM HEI that's the issue.....well........it AIN'T.
 
Yeah, like EVERY SINGLE GM product from 74 to about 85. Think about that a minute. EVERY SINGLE GM PRODUCT. We're talkin HUNDREDS of MILLIONS of vehicles. So to say it's the GM HEI that's the issue.....well........it AIN'T.

I know and if I didnt work on old cars for a living I would probably never think twice about them.

It seems like i have a higher than normal rate of problems with them.

After the two dead ones in a row and a third that would not keep time (all new, all from summit) now I look real hard at them and put the timimg light on just to see what they are doing.

At this point I dont trust em.
 
I know and if I didnt work on old cars for a living I would probably never think twice about them.

It seems like i have a higher than normal rate of problems with them.

After the two dead ones in a row and a third that would not keep time (all new, all from summit) now I look real hard at them and put the timimg light on just to see what they are doing.

At this point I dont trust em.

Which ones are you buying?
 
I know and if I didnt work on old cars for a living I would probably never think twice about them.

It seems like i have a higher than normal rate of problems with them.

After the two dead ones in a row and a third that would not keep time (all new, all from summit) now I look real hard at them and put the timimg light on just to see what they are doing.

At this point I dont trust em.
Are you buying whole distributors or piecing stuff together?
 
I dont recal what those 3 were exactily. They were all for a brand new chevy stroker 383. The motor was drop shipped through summit (383 crate) with a bad distributer.

(Would not keep time)

Two more were sent out (no charge) and both units were dead on arival.

After that I installed a probillet and digital 6al and the car went out the door.

The vendor was VERY good about the entire thing and I still buy crate engine through them today.
 
Are you buying whole distributors or piecing stuff together?

The 3 prior failures were all new units. Not reman (as far as I know) and ordered as complete units. (Installed in a turn key "carb to pan" crate engine.)

Well the first one was installed. The next two I put in.

:)

It seems no company ever covers my labor for replacing their shitty parts..
 
The 3 prior failures were all new units. Not reman (as far as I know) and ordered as complete units. (Installed in a turn key "carb to pan" crate engine.)

Well the first one was installed. The next two I put in.

:)

It seems no company ever covers my labor for replacing their shitty parts..
Naw, labor coverage is gettin to be a thing of the past. Even when I was with O'reilly they denied everything and I hated it because I was friends with most of the shops since I was a mechanic too. It's not right.
 
I had two Mallory 4 pin HEI modules purchased from Summit fail within the one year warranty period. Actually the first one failed within the one year warranty, Summit replaced it and the replacement unit also failed within a few months. The engine would shut down, no spark,,,. Had a good heat sink, good ground,,, installed a new genuine GM 4 pin module three years ago, no more problems.
Some aftermarket Hei modules are poorly made. Get a genuine GM module and you will be fine.
 
Yeah it sucks.

Not totaly the same but along the same lines and with summit.

We buy a lot of parts from them. Like all our parts. Id say 99 percent of our parts come from summit.

My dad dont live is a super great area and one day a stick of cage tube got stolen off his porch. Summit has both asresses on file. Our shipping adress is the shop and the billing is his house. Some time summit dont get it right.

I call summit and say we never got it (the cage tube) and she starts giving me the what for... kinda asking "are you sure you didnt get it?" Wink wink...

I said, you better look back at our purchase history before you ask that again.

I just took delivery of two 1250CFM dominators (that got dilevered ON THE PORCH AND NOT TO THE SHOP ADDRESS) and you think Im gonna lie about some missing cage tube?

as if after spending stupid amouts of money Im gonna lie about taking delivery of the cheapest thing i have ordered in the last year?


:BangHead:

:lol:


And now back to our regularly scheduled program.
 
I think it's about to the point really that if you want something that's 100% quality, buy an original unit and rebuild it with NOS factory components. That's what I did with the electronic ignition distributor in Vixen and it turned out great. I think by and large, failures with chinkesium parts fall far below those that succeed, it's just that you never hear about the good ones, because they're doin what they're supposed to. Everybody always makes a fuss about failures. Just think of how many millions of those ready to run HEI distributors have been bought since they came out for literally every make. I fully agree they could be built with better stuff....and Lord knows you got some bad luck. But we've all seen stuff like getting three bad alternators or starters or whatnot in a ROW from auto parts stores. We used to see it more than we wanted to at Oreilly. Unfortunately, that's just how it is. dammit all.
 
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It really is sad, the poor state of replacement parts. Personally I think the DOT and NHTSA ought to be all over that ****. Much of it is a safety issue, things like brakes dimmer switches, hell even wheel bearings and certainly front end parts.
 
It really is sad, the poor state of replacement parts. Personally I think the DOT and NHTSA ought to be all over that ****. Much of it is a safety issue, things like brakes dimmer switches, hell even wheel bearings and certainly front end parts.
Hay buddy, you KNOW dang well if we all had airplanes we wouldn't be having this problem.
 
Hay buddy, you KNOW dang well if we all had airplanes we wouldn't be having this problem.

Yeah because we could not afford to keep up with the "hours" on our cars and most drivers would not pass the physical, let alone the book.

Edit- I will say this tho. I still toy with putting a Hobbs hours gauge in the Dart race car. Why dont more cars run hours gauges?

Race car engine wear aint measured in miles.

All the hot race boats run hours. Heck APUs, tractors everything besides cars run hours.
 
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Yeah because we could not afford to keep up with the "hours" on our cars and most drivers would not pass the physical, let alone the book.

Edit- I will say this tho. I still toy with putting a Hobbs hours gauge in the Dart race car. Why dont more cars run hours gauges?

Race car engine wear aint measured in miles.

All the hot race boats run hours. Heck APUs, tractors everything besides cars run hours.
Das a good kwesshun.
 
I met the owner of this fine aircraft as He was exiting my buddys shop. (My buddy fixes engines..)

We some how ended up chatting and he mentioned this beauty.

20210111_122717.jpg



Well you know. It was fine last time and its all sorted out now.

:lol::steering:

It was a hell of a ride. We all know engines fail but when you are in a single engine racer (that just failed) it truly makes you wonder about parts quality.
 
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Cope,
What are those numbers in post #1? Is that dwell or centri advance? If dwell, it is GOOD. Are you aware that the HEI body needs to be grounded to produce spark [ Chrys dist do NOT need to be grounded ]. I mention this in case you are bench testing them, out of the engine.
I have only ever had one HEI dist fail & it was an expensive DUI dist. I have used heaps [ lost count ] of Chinese HEIs here & have never had a failure. They are well made.

And what do mean when you say you have never had one work 'right'?
 
The numbers are advance.

Im guessing the inside are shot and wobbling all to hell. This car has 8-25 degrees of advance at idle and i stopped pushing the throttle at 3,500 RPM at 49 degrees with iron heads.

I figured i should back down.

And i hate GM HEI ignitions. They never work right and have unstable timing.

Like crazy unstable timing. Say 8 to 25 at idle.
 
And what do mean when you say you have never had one work 'right'?


At this point I am done trying to fix or even replace them. I think they are ugly and they just dont work for me.

I have never had a single MSD probillet ever do anything but work.
 
It really is sad, the poor state of replacement parts. Personally I think the DOT and NHTSA ought to be all over that ****. Much of it is a safety issue, things like brakes dimmer switches, hell even wheel bearings and certainly front end parts.
.
Whoops, Sorry Y'all, whole point was China made aftermarket Junk....
I was 2nd owner of a 01 Ram, 4 door, tow package, king and queen ac, heated leather seats, really nice truck. 900 bucks ( I got a deal because I worked for the original owners, for years, cheap, but, when you have a commie in office, and you live in a South Florida semi- 3rd world construction area...) this was right after the deceased ex Jacked my 66, and wrecked er, any how, truck was kinda smacked up, had over 250,000 miles on her. Went to go meet a chick in Bradenton. Had a loose front hub. Got one from Advance, installed, made the trip, continued to daily her and work out of her, until a 135 $ assembly let go as I was contemplating getting on the Veterans Expressway. Took the Tire, rotor, half the hub, part of the ball joint arm and steering arm, was all attached to the wheel. THANK GOD, I was doing 5 mph, a mile from home.... something said, said, don't go. Should have sued the living **** outta them...lost the Ram over that. But, God, working through a Brother, had a Mint 2000 Jeep Grand Cherokee Laredo, dropped off in my driveway, a/c blasting.. for 800 bucks...Praise The Lord! ( should have never worked outta her)
 
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