I have a 79 f250 with a STOCK 400m and im looking to upgrade to a hei distributor but what gear should i get the steel or bronze gear?

 

You don't want to use a steel gear with your factory cast iron cam - it is harder and any wear will be on the cam rather than the distributor gear. Go with a cast iron or bronze gear. Steel gears are intended for use with hardened steel camshafts, which are used in factory setups that have roller lifters. Flat tappet cams are generally cast iron. If a cast iron gear is an option, I would go with that since the bronze will wear faster, but take either over steel because you'd rather replace a distributor gear years down the road than destroy your cam.

 

I wouldn't say a GM HEI distributor is an upgrade....... Its hard to beat the stock Motorcraft.

 

I would agree there. The Duraspark II system is solid if you have an OEM ignition module.

 

Alright maybe i will just leave it the way it is and replace the wires because it runs great the way it is there any special wires you guys would recomend for a stock ignition like this?

 

What's your goal here? You say the truck runs great: what do you want to change? Straighten up the underhood wiring? Knowing more about what's motivating your questions will help us give better answers.

 

Im mainly trying to clean it up under the hood and i was looking at some blue wires to match the valve covers and heater core hoses so it all matches and the reason i was looking to get a hei distributor is for better spark and to eliminate the external coil and go away from points and not spend alot of money but if the stock one is a good set up i will leave it and just get plug wires because the ones i have are old and need upgrading

 

I wouldn't anticipate better spark from an HEI, just fewer external wires. And if your truck is running well and you're not adding a supercharger or something, there's no reason to think you've got a problem with the quality of your spark. If you did, it wouldn't be running well. And HEI systems don't create any stronger a spark than Duraspark systems do in any case... you'd have to go to an MSD capacitive discharge ignition or something along those lines to really improve on it.

If your distributor is old enough to have points rather than the Duraspark ignition module, it is possible to swap to a Duraspark or HEI style electronic ignition; there are also drop-in retrofits from Pertronix that will eliminate them while retaining your current distributor.

There are definitely guys here who have put in an HEI, often when their original wiring is damaged or missing. I'm not a fan of the look myself (I think that distributor is uglier than having the external coil and ignition module), but some like it. Arguably, there are some design advantages to the Duraspark setup, but not ones that are likely to make any practical difference. The one thing to watch out for with Duraspark is aftermarket ignition modules have somewhat variable quality... You'll definitely be able find resources around here for how to wire it up, etc. if you go the HEI route though. Just avoid steel gears whatever you do.

 

Alright i did hear that the steel gears destroys the cams...and if i went with a hei setup what would you recomend for a cheap but reliable setup? I was looking at some assault racing and procomp ones but not sure if it will be real reliable i am going to be using this truck as an everyday driver

 

Taylor makes a good set of wires. I had a set on the 400 in the 79 I had, but lately I bought a set from NAPA that look real good and seem to do the job for the 460 I have.

 

Alright do you know any more info on the cheaper distributors on eBay like the pro comp and assault racing brands because i wouldn't mind putting a hei distributor in to get rid of the external cOil and go away from points with out spending alot of money

 

You shouldn't have points in a 79, unless someone did some swapping. If it runs great, why mess with it??

The quality of the aftermarket HEI distributors is poor, most throw them away after trying to get them to simply fit the engine correctly, let alone spark like they should.

Buy any quality plug wire, you'll be fine. Avoid chinese garbage sold on ebay.

If you do decide to swap distributors, reuse the gear that is currently on your distributor. It is already mated to the gear on the cam, & is most likely a quality genuine Ford part. If that gear will fit the distributor you choose to install that is. Many aftermarket distributors have horrible quality control & OEM gears won't fit them. Then you run the mystery metal aftermarket gear that comes with the distributor & it chews up your cam gear, sending metal shavings thruout your engine, trashing $$$$ parts. All to get rid of the external coil on an engine that runs "great". No thanks!

 

You have an excellent point!!all my questions were answered and i appreciate your time thanks alot

 

Agree stick with the OE gear or if needed a quality OE replacement part. Also agree the Duraspark is a solid system if wiring is OK and with a good module... sounds like yours is. FWIW I run the Duraspark box installed in 1978 on mine... with a spare Motocraft box from Rock Auto behind the seat if needed.

In general, the distributor gear and cam make a "wear pair". For good life, hardness of the two parts needs to be different so they do not "fight". The OE cam is iron (kinda soft) and the OE gear is steel (kinda hard). They make a "wear pair". Bronze gears are intended for steel core roller cams. The bronze is softer than the steel gear on the cam to make a wear pair. Only problem is the bronze is quite soft and wears out quickly. Not needed and not issue in your situation I think.

 

I would look at wear the other way around, from an engineering perspective. You want a relatively good match between the properties so neither wears excessively, but you *definitely* want the cheaper, easier to replace item to be the one that is more prone to wear.

Ford used steel gears with the later-model steel roller cams. There's a good match between the material properties and neither wears quickly. If you use a steel gear with the ductile iron gear on an older flat-tapped cam, you'll wear down the *cam* gear quickly, which is a much more problematic replacement than if you wore down the distributor gear. If you use an iron distributor gear (stock in these) with a steel cam, it will wear more quickly, but at least it is easier to replace than the cam...

Many aftermarket cam companies recommend a bronze gear by default because it's not likely to cause damage to any cam, and they don't harden their cams in the same way that the factory did to achieve hundreds of thousands of miles of life when working with a hard steel gear.

In any case, a steel gear is the one thing you must avoid unless you have a steel roller cam.


Personally, I'd just stick with the stock Duraspark and not worry about it, but it's not my truck...