Electrical A 258 HEI discussion

[NotTJ]

My 78 has the factory ignition. I have a new brass cap and rotor coming. It has a big accel coil. For the short period of time I ran I before removing the head (broken exhaust bolt hole) to replace it ran fine. I mean it ran fine revving a little in the driveway but really nothing to cause alarm. Since this is my trail vehicle I’d love to simplify the ignition section of the engine. I see HEI for like $150 with wires. These are aftermarket of course. Is there any good reason for me to ditch all the factory ignition and just get an HEI? Would it allow me to ditch the ignition control module and wiring? I see folks mentioning swapping the amc distributor gear onto the aftermarket hei…I could do that assuming my gear fits but another thing I wouldn’t mind is finding an hei made by a real OEM. My old CJ had a Buick V6 and a Buick hei fit. Is there anything like that available for my engine? Boy I’d love to ditch that module, the coil hanging off the head, the ballast resistor, and just have a one piece unit to handle it all but I also don’t know if I want Chinese coils and such (I assume a stock gm coil can be had in the place of the China coil).

 

[Armyvet25]

CRT HEI has correct gear, no need to switch, most popular, quality

 

[CJ]

@NotTJ - Dist vs cam gears were a huge problem not so long ago when a ton of junk (mainly from china) hit the aftermarket dist scene. Dist gears were not the correct hardness of the cam whether stock or aftermarket. This ended up with a lot of cams and or dist being destroyed. Most vendors are on top of their game now so it's usually not an issue. But if you really want to not take a chance you can always swap out your gear with your original (though that is usually not necessary.)

As for your situation, I like the HEI dist. But, I would not remove the stock coil system or box / wiring. I like backups, so go with an HEI and keep your old equipment in place and with you. If your on a trail and you have a problem - a ten minute dist swap and your back on the dirt...

There are many dist out there and DUI (Davis Unified Ignition) is a very popular brand but can be pricey. As far as I know they are still made in Tennessee. -->> +dui +distributor +amc +258

 

[NotTJ]

A friend told me an HEI from an 82 C10 with the 250cid engine would fit a 258. Is this correct? I like this option because I can get a remanufactured GM instead of a china repop.

For now I might just keep all the factory ignition until it gives me problem.

 

[CJ]

A friend told me an HEI from an 82 C10 with the 250cid engine would fit a 258. Is this correct? I like this option because I can get a remanufactured GM instead of a china repop.

For now I might just keep all the factory ignition until it gives me problem.

I've never heard that but I do know the dist gears are cut opposite.

 

[caveman]

I bought a used GM HEI local and ordered a gear from ebay. Wrapped the old one up in plastic and stored it in back of jeep just in case. Jeep ran smoother and seemed to have a little more power. Ran it that way for a year and decided to get rid of old distributor and magic box. ten years later I'm still running that used HEI. Would recommend.

 

[TSB8C]

A friend told me an HEI from an 82 C10 with the 250cid engine would fit a 258. Is this correct? I like this option because I can get a remanufactured GM instead of a china repop.

This is true. Get an HEI dizzy from '78-'82 from a salvage yard, looking at Chevy vehicles with the 250 or 292 I6 engines. Also grab the 3-wire connector for the dist cap. Then you'll need a new dist drive gear since the Jeep version is cut in the reverse direction as the GM. The drive gear found on stock '79 & later Jeeps with the Duraspark ignition will not fit properly on the HEI dist. The new drive gear you will need is part number is 3208615 from any Chrysler dealer (pricey), or this is the gear found on '83 and later AMC V8 engines and will fit perfectly on the HEI's dist shaft.

You will see brand new HEI setups, with wires and all, on eBay and other places for about $125. But these are usually the cheapo China and not worth the money.

Also be careful of some higher quality HEI dizzies that advertise the hardened drive gear, as those have sometimes been known to eat your cam shaft. CRT Performance is one such offering.

So like Caveman said - get a GM HEI from a GM I6 engine, order an AMC V8 drive gear, install new cap/rotor/wires - good to go.

 

[NotTJ]

This is true. Get an HEI dizzy from '78-'82 from a salvage yard, looking at Chevy vehicles with the 250 or 292 I6 engines. Also grab the 3-wire connector for the dist cap. Then you'll need a new dist drive gear since the Jeep version is cut in the reverse direction as the GM. The drive gear found on stock '79 & later Jeeps with the Duraspark ignition will not fit properly on the HEI dist. The new drive gear you will need is part number is 3208615 from any Chrysler dealer (pricey), or this is the gear found on '83 and later AMC V8 engines and will fit perfectly on the HEI's dist shaft.

You will see brand new HEI setups, with wires and all, on eBay and other places for about $125. But these are usually the cheapo China and not worth the money.

Also be careful of some higher quality HEI dizzies that advertise the hardened drive gear, as those have sometimes been known to eat your cam shaft. CRT Performance is one such offering.

So like Caveman said - get a GM HEI from a GM I6 engine, order an AMC V8 drive gear, install new cap/rotor/wires - good to go.

My 1978 distributor drive gear is also no good on the GM HEI?

 

[TSB8C]

I actually believe that all 304, 360, and 401 AMC V8 engines have the same drive gear, even though they did change the distributors around 77/78. When the distributors were changed, part numbers for the components also changed. So a pre-78/79 gear I believe is the same but with a different part number. If you have a gear from a 78 AMC V8 engine's distributor, I believe that will work just fine. If looking to purchase a new gear, just search for part # 3208615 at your local parts guy or 4WD Hardware or Crown (~$25), or local Chrysler dealer (~$40). Here are some other part numbers that cross reference to the same gear:

MOPAR = 3208615
NAPA = BK 6551283
4WD Hardware = 3208615

 

[NotTJ]

I actually believe that all 304, 360, and 401 AMC V8 engines have the same drive gear, even though they did change the distributors around 77/78. When the distributors were changed, part numbers for the components also changed. So a pre-78/79 gear I believe is the same but with a different part number. If you have a gear from a 78 AMC V8 engine's distributor, I believe that will work just fine. If looking to purchase a new gear, just search for part # 3208615 at your local parts guy or 4WD Hardware or Crown (~$25), or local Chrysler dealer (~$40). Here are some other part numbers that cross reference to the same gear:

MOPAR = 3208615
NAPA = BK 6551283
4WD Hardware = 3208615

Thanks - was asking if my stock 258 gear would work on the GM HEI? Sounds like I need an AMC V8 gear on a GM HEI

 

[TSB8C]

Yes, you need a stock AMC V8 gear to fit the HEI dizzy. The gear from a stock AMC 258 dizzy will not fit onto the GM HEI. A bit confusing for those not familiar with this mod, in that you need a gear for an AMC V8 engine to make the GM distributor work in your AMC 6-cyl engine.

 

[NotTJ]

Just bought a Wagoneer distributor on eBay for $25 shipped. Will get a reman distributor when I find a deal. We in business to make it look cleaner under there.