Mopar Ignition Boxes and General Ignition Questions

[My imp]

Geez, lighten up! I was just trying to make a point that people who say they'd NEVER run GM parts on a Mope, or Mope parts on a GM, wont go very far w/o the New Proccess transfer case, or Saginaw steering components. Yeah, 8.75" came in auto HEMI cars. I was talking both. I also said IF, not I was. With all things considered, weight, cost, availability, along with parts availability, & cost, there's a reason you see 9" Fords in so many vehicles. They're a stronger set up. 8.75" & 9" are what I refer to as a poor mans quick change. You can have your various center sections ready to swap in a short time period. I'm not now, nor do I plan on making enough hp to need a Dana or 9" Ford. I have my trusty 8.75" out of my '66 Coronet that I'll put in my Imp. I've been looking for a reasonably priced core trans. Everyone must've checked off the 24k gold case option, or their just real proud of being able to pull a trans, because the $400-$700 I've been seeing on Craigslist are too rich for my blood. They're ALL rebuilt, just ask the person selling it. Oh, then how long's the warranty? There is no warranty. Oh, then you have a core. I've heard all the horror stories of swap meet parts. I buy, you fly doesn't work for me. Nor does, "It ran fine when I had it in my car!" If I tear something apart to inspect it, more than likely you'll be re-sealing, re-ringing, rebuilding some, or all anyways. So why pay for a rebuild, if you're going to rebuild it.

 

[NoCar340]

A Ford 9" is no match strength-wise to a Dana 60. Guys step up to Danas when they're consistently breaking the 9" design using all the gee-whiz aftermarket stuff. But hey, that's not why I'm posting.

Ramenth is dead-on about the GM HEI swap, though he didn't go all the way as to why it's a waste of time (in my opinion) as a swap goes.

First of all the HEI module, in my experience, is less reliable than the Mopar ECU. Both designs are solid state, but the Mopar design incorporates typical Chrysler overengineering. If you can figure out how to remove the potting compound from the back of one (I used straight muriatic acid) you can see the components are far more robust for an engine-bay environment, not that anything's going to get in there anyhow. The potting compound also acts as a vibration dampener. The HEI module is not designed to be out on its own in the engine bay. Clean, neat wiring on the Chevy Craft installation, but one good puddle and sayonara. Darkness falls across the banks of cylinders.

Next we have the spark issue at low RPM. Is HEI that much better? I don't think it is. For one thing, spark intensity is much more crucial at higher RPM where cylinder pressure increases and dwell time decreases. At cruise and part-throttle acceleration, it doesn't take a hell of a lot to light the mixture, which is very lean anyhow. Lean mixtures light more easily. Timing is far more crucial. A great spark is always wonderful, no doubt, but when you're having the most fun with your car it's further up the RPM scale. Before we condemn the Mopar ECU's low-RPM performance, though, here's the most neglected aspect of the system: the ground circuit. Nearly all aftermarket ECUs are of the 4-pin variety, though you can still get the 5-pin if you look. The ground through the case on the 4-pin unit is absolutely critical. How much attention do you pay to that contact area before you have a problem? "I hate the Mopar ECU... the back melted out of mine more than once" is something I've heard over and again, and it never occurs to the person saying it that it's most likely a ground issue. Yes, check the wiring. Those bolts that hold it to the firewall/inner fender/bracket (and in the case of the bracket, the bolts that hold it in place as well) are part of the wiring. They are the ground wire. It's as simple as that. Anything but a perfect ground compromises performance, particularly at lower engine speeds when the alternator may not be cranking out the optimal 14.4V.

Speaking of voltage, the Mopar electronic ignition was designed around an input voltage of 12.6V. This is the nominal charge of any 6-cell lead acid battery; each cell produces 2.1V nominal though it can vary by a few tenths in either direction. The HEI system, on the other hand, used 14.4V as the design parameter for input voltage. Is your alternator brand new every single day, or does it wear and lose voltage over time. Is your wiring fatigue- and corrosion-proof, or do you have the same wiring as the rest of the world? So, at 13.5 volts, the Chrysler system is getting a .9V boost, whereas the HEI is operating at the same number under it's design specification. Food for thought.

As ramenth pointed out, HEI output tapers off dramatically starting around 4,000RPM. The funny thing about that is, of course, that's when it's most likely to see that 14.4V it loves so well. I have run stone-stock, nearly 20-year-old factory Chrysler systems with the original, date-coded ECUs well over 7,000RPM. Can the HEI be cured? Sure. Just buy a $120 MSD module... it works like a charm. I've watch racers and street guys chase their tails for years because they misdiagnose the mighty HEI's Achille's heel as a fueling issue. I learned quickly enough when I was running a Pontiac, but being a Mopar guy I obviously didn't know what I'm talking about when they'd tell me their car "lays over" at 4,700RPM. Of course, they could never catch the Trans Am that no-nothing Mopar jackass screwed together on a whim, either. :icon_biggrin:

As I said further up the page, the module should be your last point of concern unless it's fried. If it's fried, find out what fried it (I bet it was the ground). Sharpen up the rest of your ignition system first, preferably by the guidelines I laid out above which come from 27 years in the industry and 30 of working on hot rods. When the time comes, if want a Chrome unit you should probably already have a good aftermarket coil like the MSD Blaster 2, Mallory, Pertronix, etc. The stocker will live for quite awhile, but it will get pretty hot at that dwell time which will ultimately shorten its life. No such concerns with an Orange ECU, but again: the Gold is absolutely out for anything but a pure race application. I learned that one the hard way, and it's an expensive lesson. You could maybe make it live in a driver by putting it directly inline with good, cool airflow but then it'll just pop the coil. Any coil. Guaranteed.

I'm not going to bash others for doing it, and if it works for them I'm happy that they're happy. I wonder whether there was some underlying problem, though, and I probably won't get to find the answer since no one likes to admit they might have gone to a bunch of trouble for no gain or to put a band-aid on a broken leg.

Your car, your call. Whatever you prefer is where you're going to go with it. The ignition system for the Imperial, and probably the Challenger too, will be completely Ford-based. Hate me all you want, but it's more firepower than an MSD 6 and I can control my timing with a laptop. Timing curve? Actually, it's a 3D timing map. Total control over four ignition coils. :eusa_dance:

 

[ramenth]

Geez, lighten up!

If you thought I was being uptight then you haven't seen me actually go off. :icon_cool:

One of the things I take into account when I answer posts is that we're not the only ones reading 'em. Besides those who have responded in the thread there's hundreds, maybe thousands of people over the coming years who may look for information on the web and google or bing or yahoo might bring them to this thread. I have a tendency to address a wider audience.

Yeah, 8.75" came in auto HEMI cars. I was talking both. I also said IF, not I was. With all things considered, weight, cost, availability, along with parts availability, & cost, there's a reason you see 9" Fords in so many vehicles. They're a stronger set up.

There's a reason you see so many 9" in vehicles, too. I'll get to that in a minute. If you break an 8.75, you'll break a 9". Time to step into a Dana.

I was just trying to make a point that people who say they'd NEVER run GM parts on a Mope, or Mope parts on a GM, wont go very far w/o the New Proccess transfer case, or Saginaw steering components.

Actually, I advocate the best parts for the build, within someone's budget and within the build. For example: Chevy inline six rocker arms in my Ford inline six. Using a Dodge sourced NV4500 for the same build and I'm exploring the idea of using a modern Dodge sourced Dana for the truck for a few reasons. It's bigger and has the accessibility to big rear disks. And... the modern Dodges use the same bolt pattern as my older Ford. So, I'm not against mixing and matching. To quote a member of fordsix.com when someone wrinkled his nose at using Chevy rocker arms in his Ford, "if it fits my Ford and works, it's now a Ford part."

But, here's where things get sticky... Is the ever ubiquitous quote of "put a 9" in it if you're building major horsepower" the truth of the matter or a matter of myth? Once upon a time when Ford 9"-er's were everywhere (I can't find a decent used one around here for less than a grand) thanks to Ford selling millions of Mustangs all the way up to Lincoln Versailles, plus the F-series, but now, not so much. Over the years, a lot of racers, especially circle track guys working on a budget, could go to the local junkyard and pull 'em by the dozen and cheaply put a set of gears in it. For the price, as you pointed out, they could set center sections up and it was now a "quick change." And they were a helluva lot better than anything GM produced.

People saw them on the circle tracks, saw the availability of them, heard of the circle track guys talking about how bulletproof they are and then the reputation took off from there. Are they strong? Yes, they actually earned the reputation, unlike a lot things of which the myths have propagated over the years.

Now, let's take the underrated 8.75". Ford used the nine inch under a lot of things, as I've said. The 8.75" was used only where needed. You weren't going to buy a slant six powered car with an 8.75" unless someone optioned for it. It was held in reserve for higher horse and heavier duty applications all the way up to Hemi automatics. Take into account Ford outsold Chrysler -what? - three to one? Meant a lot more 9"-er's were available and the popularity of the rear meant the aftermarket was able to catch up in a hurry, offering a larger range of parts and pricing.

Now, if roles were reversed and Chrysler was at the top of the sales chart and used the 8.75" as much as Ford used the 9" then I can almost guarantee the roles would be reversed: the 8.75" would be the go-to rear and the 9" would be underrated.

One of the things to take into account when talking the Hemi and 440 6bbl cars, too, is warranty. Chrysler, just like all the factories at the time, unofficially sanctioned street racing. You weren't gonna buy a stripped out Hemi 4 speed Road Runner or one of the A12 cars to just drive it back and forth to work. You were going to flog it, looking for that stop light action and back road racing. It was gonna take a lot abuse. That meant going with a rear that was overkill to stand up to street legal drag slicks and sanctioned races at the strip.

Kind of like when they released the Maxie's with the the three speed as the only manual transmissions. The three speed wouldn't have to warrantied left and right. Warranty claims lose money.

There are several reasons why I have a tendency to address threads like this. And that's to disspell some of the things I read on the 'net.

Lets take for instance the "use a 9" or Dana for really high horse applications!" Like I said, if your break an 8.75" your gonna break a 9"... go straight to the Dana.

Right now, because the supply of affordable 8.75's and 9" are drying up the A-body guys all I ever read is using the Ford 8.8. It's become such a mantra from the 'net that no one listens to a former Ford tech shouting at the top of his lungs that I've seen stock mid-2000's Mustangs rip an 8.8 to shreds. I've seen V8 Explorers and Mountaineers rip 'em to shreds. But when you have a hundred guys shouting back at the top of their lungs "Use the 8.8!" It's hard for one loan voice to be heard.

One of the ever present myths perpetuated on the 'net is that you can't - absolutely, positively -can't use single planes on the street. I've got an engine here that says otherwise. Yet, for the experience that literally thousands of us have with single plane intakes on the street there are thousands more taking to the 'net saying that it's impossible.

This cam needs this gearing and this gearing only! Umm... okay. Yup, that's right, the cam is affected by the gearing. :roll: Funny how you can't "cruise" with this car because you went to 4:10's because this cam had to have 'em, now you're looking for an OD to bring the gears down to something "streetable." Then what the f*** is the point of putting short legs in it? Oh, because for all the "knowledge" on the 'net, that's what the parrots say.

Everyone is on the Edelbrock kick lately. You have to have a set of Edelbrock heads to make any serious horsepower. Nevermind you just invested a grand for a set of heads that flow like a set of 915's out of the box and now you're gonna spend just as much to get 'em to flow better as if you just stuck with the iron 915's and flowed them. Nevermind the idea that it's a street car, not a drag car, and the weight saving on aluminum doesn't matter one bit. Nope, constantly push the idea that you have to use aluminum to make any serious horsepower. Tell that to the FAST guys.

Speaking of Edelbrock, did you know they're the only ones who build an intake that works on Mopars? Yup, that's what the "experts" keep parroting. Yet, when you mention Weiand, Offenhauser, and Holley, those same experts come up with excuses as to why to use an Edelbrock, not reasoning. "The Edelbrock is cheaper." Oh, okay, just a thread ago, the "expert" is recommending a build where money is no object and use the best parts available. Now he's saying go with Edelbrock because it's cheaper. Which is it?

Now, you have guys spreading the idea the HEI is the only ignition set up to use. NoCar went into a lot more detail as to why it isn't. Yet, the "experts" are screaming by the thousands that it is, the parrots are picking up on it, and it's taken a life of it's own with no one listening to well thought out reasons like NoCar posted. One loan voice in the seas gets drowned out.

Years ago, on another forum, I sat back and watched the parrots claim you can't run 360 heads on a 318. Contrary to what Chrysler did with the 318-4bbl. A supposed "expert" said it couldn't be done. This supposed "expert" said you can't put 2.02 intake valves in a Chrysler head and have it be "streetable." Nevermind the fact that 340's did just that. The parrots on the site took it as gospel and spread the word. They harangued and browbeat everyone who disapproved of the "master." They wouldn't listen to more reputable engine builders saying otherwise. They wouldn't listen to others with a completely different experiences. Once the "expert" was exposed as a complete fraud they changed their tune. Suddenly, the "master" was trash. No one should listen to him. Some of us tried to tell them that, but with no real world experience of their own, no real ability to sift through the disinformation, they didn't get it. Now, like a lot of drones, they're looking for another "leader."

When it comes to information on the 'net, a lot of it is voiced by parrots. The question is can the reader, looking for answers, sift through the parrots and get to what's real or prove it out on their own.

 

[kkritsilas]

Thanks for all the information. I will keep an eye out in the junkyards for orange and maybe blue Mopar ignition boxes. I have seen a bunch of third party boxes, which may or may not be any good, but I will be aiming for factory original orange/blue boxes.

Kostas

 

[NoCar340]

Methinks ramenth and I would get along famously in person. It sounds like he's learned from experience, the same way I did.

I've been told many things I "could not do" over the years on street cars: run a single-plane, make Six Pack Super-Stock carbs (mechanical secondaries) work with a 3.23-geared automatic transmission car, daily-drive W2 heads, put a daily-driver Crossfire-injection '82 Camaro into the low-13s, etc. ad nauseum. I didn't do these things because I was told I can't, I did them without input and then dealt with the shock & awe from "experts" asking me how the hell I not only made it happen, but how could it work so well? "Doesn't the fuel puddle?" (single plane), "How did you keep it from bogging?" (Six Pack w/4791/4792 carbs), etc. If I didn't know, I asked. I didn't ask JimBob on dualplanes.com/forums, I f__king well asked Ray Barton or John Lingenfelter (R.I.P.)!

I was told about the HEI swap years ago. I initially laughed at it, due to my experiences with it when I ran Tin Indians, but hey--maybe there's some merit there. My extensive research told me otherwise, and whether others care to accept it or not is fine by me. You won't find it in my car, and if a friend has done the swap and is having ignition issues the first recommendation I'm going to make is to rip it back out.

Aluminum heads? Don't get me started, but my current favorite "upgrade"? Without a doubt, it's hydraulic roller cams. What a joke... they're the single fastest way to spend enormous money on a downgrade. Wait, what? Sorry, kids, it's nothing more than a marketing scam, and anyone who knows the first thing about camshafts that isn't trying to sell you one can tell you why. I call 'em like I see 'em, and knew long before they were even readily available why I should avoid them. If you think for one second that roller cams were developed for low friction, you are seriously misinformed.

 

[Monkeyed]

One of the things I take into account when I answer posts is that we're not the only ones reading 'em. Besides those who have responded in the thread there's hundreds, maybe thousands of people over the coming years who may look for information on the web and google or bing or yahoo might bring them to this thread. I have a tendency to address a wider audience.

nice to see someone who understands how cars AND then internetz work for a change! :headbang:

 

[My imp]

Where did I say the 9" was stronger than the Dana? I re-read 3 times & failed to find that part. I said it was lighter. & cheaper than a Dana? Well, isn't it? A 9" is stronger than an 8.75", while not by leaps & bounds, it is stronger. I said the same things you said, best parts I can afford, best overall setup, etc. my slightly warmed over 360 needs neither an 8.75" or a 9". Let alone a Dana. Maybe, if I find the parts I'm looking for , I'll need them. But not now. The original question was how a Mopar guy would react to using GM parts on their car, the "purists". All I meant was that I already do, & don't care. Just as the guys that thought less of you for driving a Mope instead of a Poncho. Many of them have no idea New Process is owned by Mopar. My shop foreskin in Arcadia swore by Cummins diesels, would t have anything else. Until I told him Chrysler's owned Cummins since '64. Now, their junk. Got a 5gallon pail of near new Thermoquad's off of every Chrysler engine in the yard. Pulled them all & replaced them with Q-Jet's (loved GM, hated Carter & Chrysler). Most were still under warranty, but he didn't care, Carter's are junk, just ask him!

 

[NoCar340]

Apparently he's not aware that GM used mostly Carter carbs on their musclecars in the '60s. :eusa_doh:

I think that the point was, if you need an 8.75" there's no reason for the expense and hassle of going to a 9" for the marginal upgrade in strength. If you find yourself breaking 8.75", you may as well go straight for the Dana.

A lot of headache with the 8.75" can be avoided by not using the small-pinion 741/657/X casting center section. While its 1.375" pinion stem is still larger than that of a Ford 9", the 9" pinion-snout bearing really makes up for the lack of shaft diameter when it comes to pinion deflection & breakage. Shaft not big enough? Get more balls! :icon_biggrin: I have a 985 case (which is the early version of the 742) for my Imperial. Strength should not be an issue, even with manual-trans shock loads and potentially well over 500HP. Though I'm not building the car to be a clutch-dump, power-shift oriented machine, well, we all have our moments. I have a 489 case for my Challenger, which will likely be more abused than the Imperial. Again, strength won't be an issue... but then again, if for some reason I need more strength, I'm just as apt to go with a 9.25" as a Dana. It's probably 95% as strong, cheap and plentiful, and there are tons of gearsets and other service parts available for it. Converting a truck Dana is a nightmare best avoided, and a car-specific housing is neither inexpensive nor easy to find.

For me, an 8.25" is absolutely out of the question. I've seen too many failures at every point in that rearend, and having one under the back of my car would leave me a Nervous Nelly. I'm more of the set-it-and-forget-it type, and I don't need blown spider gears, chewed-up axle shafts, folded crush sleeves or dropped C-clips ruining my day.

Back to the point of running non-Mopar stuff, and the ignition in particular: It's your car, it's your money, so do what you like and to hell with the critics. I chose Ford EDIS for total control of my ignition, greater firepower, and the longevity of a bunch less moving/wearing parts that comprise a distributor. It's not an easy conversion, by any means, nor is it cheap, but to me it's worth every penny. You can't make those kind of sparks with an MSD6. I'm using Ford's design & engineering, but not one single Blue Oval part. At one point I even thought about using '80s Impala composite headlamps behind the hideaways, but the aesthetic only comes into play at night, with the doors open, so it didn't seem worth the expense (the fitment is pretty easy, actually). My injectors are Delphi, a former GM division. Boo hoo. It's what works for my setup, and no one has to like it but me. I think everyone should adopt that last sentence as their own personal mantra. And as my good friend Ed likes to say about his carved-up, real-deal '69 Charger R/T, "If you don't like it, buy it at my asking price and you can make it the way you think it should be."

 

[ramenth]

Where did I say the 9" was stronger than the Dana? I re-read 3 times & failed to find that part. I said it was lighter. & cheaper than a Dana? Well, isn't it? A 9" is stronger than an 8.75", while not by leaps & bounds, it is stronger.

Calm down, Larry. I never said you said that a 9" is stronger than a Dana. What I was pointing out is that if you're gonna break and 8.75" you're gonna break a 9", too. If you're afraid of breakage, might as go with the Dana to boot. (As a matter of fact, I said it a few times.) I also pointed out more than a few reasons as to why the 9" has earned it's reputation as being tough and cheap and why, if the roles were reversed in sales and popularity, the 8.75" would be the go to rear and the 9" would be the underrated rear of choice.

But as far as being cheap, like I said, because of popularity and scarcity in my area there ain't no such thing as a cheap 9" anymore. The last one I priced here was a grand. About the same price as a good used 8.75 Sure-Grip. I'm looking for one to put in my F150 'cause I know the 427 stroker I'm building for it will rip the 8.8 that's in it to pieces. I might as well say screw it and go with a Dana at that point, but finding one for a 1/2 ton platform is still like pulling teeth.

The original question was how a Mopar guy would react to using GM parts on their car, the "purists".

The only car I own that's "pure" will be my '69 Sport Satellite and that's because I'm going concourse. I've already pointed out where I'll mix and match. Chevy and Dodge sourced parts for my Ford. And if I thought the HEI was all others said it is I'd go to that, too, but it's not and so I won't.

All I meant was that I already do, & don't care.

To quote myself from a post I made on FABO over guys throwing a fit for someone putting an LS engine in his A-body: "there's a lot of guys getting their panties in a wad over a car that ain't their's being built with money they ain't earned." But I'm the guy who's scratch building a cowl induction hood for his M-body, remember? The "purists" say I'm building a "Chevy" hood. But then again, the "purists" know only what's in front of them. If they'd actually bother to educate themselves, they'd see the production "cowl" hood didn't have a giant opening in the back of the hood. It was a bulge on the hood with an intake door which opened. Kinda like the "air grabber" set up's on the B-bodies.

Many of them have no idea New Process is owned by Mopar.

Was. When GM bought stake it was renamed New Venture. That being said, though, there's differences in many of the set up's NV has made. For instance, the Dodge NV4500 is a better trans for my purposes than the GM used NV4500.

 

[NoCar340]

New Process ceased to be around 1990, and New Venture was a split between Muncie & New Process, with GM having something like 39% ownership. Daimler bought out GM around 1998, then sold the whole shebang to Magna Driveline around 2005. Nobody's used an NV transmission since GM discontinued manual-transmission DuraMax diesel pickups in 2007; the last year Dodge had them was 2005. The former GM Muncie/New Venture plant in Muncie, IN is now a park. The old New Process plant in Jersey has been shuttered for nearly two years. Shaffi Keesler bought all the Muncie transmission parts and tooling from GM several years ago; what became of the remaining NP tooling and stock I'm not 100% sure. I know of one person that has owned at least some of it for over 30 years.

 

[My imp]

He only hated the Thermoquads, Yankees, Chryslers, & non-Caucasions. Come to think of it, he was quite misogynistic as well. He had a truly unique way of looking at life, not fit for print here.

 

[NoCar340]

He sounds like a real peach.