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Discussion Starter · #1 · (Edited)
I messed up and went to do a wifey emergency while shutting down Frankenmouse for a few weeks.

Frankenmouse being my 89, S15 which served as a test bed for many years which included various mix of carbs and EFI systems so the fuel pump and ignition controls are electrically divorced from the key switch and are independently switched so I could select specific system combinations but I should have used the key as a master for these switches but didn’t. So shut down includes killing the fuel pump or pumps if really pressure EFI is used and the ignition or EFI. Now that I’m staying with a carb I’m going to simple this.

So I’m in the process about a month ago of shutting it down with the expectation it will not be used for several weeks. So with a carb I shut off the fuel pump to let the engine burn out the fuel bowls then quit this is followed by offing the ignition. Well wifey dropped a jug of milk which splattered all over the garage floor so reacting to the milk emergency I jumped out of the truck to clean up the mess. By then the engine quit and I lost track of what I was doing (an age related problem). I come back to the truck to retrieve a notebook about an hour later and see the ignition is still on so I switched it off and forgot about it.

A few weeks later I have loaded the bed and want to make a dump run. It cranks with gusto but no fires in the holes. I raise the hood it’s got 5.5 psi of fuel pressure at the carb the accelerating pump provides a fuel shot on command. Crank it around on the starter but there is no spark.

Turns out the ProComp module leaked out its smoke in the hour back in the garage milk emergency. Now Frankenmouse with its external coolant returns on the to conventional cooling modification of the LT1 heads and the fact the engine is backed up as far as it can be to the firewall and still get a small cap distributor in there, this currently being a ProComp/Speedmaster 7000 with the external mount module, it is difficult though not impossible to change out the module without pulling the distributor which has its own set of process rules. Then I find I’m out of thermal paste to put between the new module and it’s so-called heat sink which is just part of the body casting outside the cap diameter so I used a glob of anti-seize, we’ll see how this works. It isn’t that thermal grease is such a fantastic heat conductor it just better than air so its purpose as much as anything is to fill any air pockets between the module and the heat sink. Anyway it runs again and we went to the dump and ran some errands so it got good and warm for a couple hours. I’ll order up a new spare module and a GM external mount module heat sink to see if this can by put in the cab away from engine heat. The Ford guys do this a lot they even have a kit.

I also did some measuring and dimensional testing as suffering from insomnia the night before and lounging in the media room watching YouTube on the big TV there was this guy railing about the poor fit of a ProComp distributor into a Chevy intake, his intake on the bench not the engine. Having several distributors of GM, MSD, and a few other types and brands I decided to test the fits on a couple Chevy and aftermarket intakes in the shop. It turns out that none of the distributors make a body tight fit into their intake mounting hole. Doesn’t matter if the intake is Edelbrock, GM, Professional Products, or Offenhauser they are all a very loose fit. So then I measured the mounting machined surfaces that make the oil passage at the bottom and the intake mounting boss at the top. Between the GM, MSD, Pertronix, and a ProComp and a couple others there isn’t more than a .0015 difference in these machined diameters between any of them. This is not say that every distributor and every intake or block is machined the same or similar tolerance but my experiment didn’t uncover any discrepancy big enough to make a difference in fit quality. So much for late night YouTubers screaming at the moon.

Bogie
 

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The fit with the intake is not a concern. But the pilot diameters with the block should be. Reason is you are meshing the gear with the camshaft gear and driving the oil pump. So a stationary fit of the distributor w/block ensures that gear mesh function. Close fitting diameters maintains distributor stability. Intake hole is only a means of getting the distributor in and threaded hole a means of locking it down to maintain timing. If the distributor diameters were small by .006” or more the “stability” of distributor and gear mesh not to speak of oil pump drive are in less than desirable functional “fit”.
 

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Thanks for the post Bogie. I know I don't use that type of a distributor but I like to learn stuff and I wish I could make a copy of al your knowledge and stick it in my head. That is very interesting in the stuff you found out. Below is what I use for my Hei control module. I have had it on my current Hei for the last year plus and the module still goes strong and its just a cheapy one and nothing special.

 

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Discussion Starter · #5 ·
Yeah, I was surprised when I went hunting through my roll arounds and boxes of stuff now yet sorted into my home shop and didn’t find any thermal grease. Since I needed the truck back on the road I grabbed the anti-seize for a substitute plus got on line and ordered a tube of the real stuff which was the Permatex because the price was right and they had next day delivery.

Bogie
 

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I am waiting on a new ignition system from Davis Unified Ignition. It is a stock chevy distributor converted to HEI with the module mounted to the outside of the distributor base. I am going to relocate the module to an easily accessible area under the dash. I have grown so gun-shy of electronic ignitions that I would like to mount 2 modules under the dash so in case of failure all I have to do is switch the wires to the 2nd module. I could probably even figure out how to do this with a switch, Nascar style.
I have been running the same ProComp distributor that you are using, but hate the mechanical and vacuum advance in the distributor. After about 20K miles, the engine started farting and backfiring, so I believe the module is dying. So I ordered the DUI system. They seem to be backed up though. I ordered it in mid January.:mad:
 

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Discussion Starter · #7 ·
The 7000 model distributor borrows heavily from a Ford of Australia design and is stuffed with renamed Bosch parts. The module is a Bosch part number 9222 067 021, it is a direct interchange for the Procomp module.

I noticed on mine that the vacuum advance appears to have lost the diaphragm but I got rained out before having a chance to check it out with my vacuum pump.

Bogie
 

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The 7000 model distributor borrows heavily from a Ford of Australia design and is stuffed with renamed Bosch parts. The module is a Bosch part number 9222 067 021, it is a direct interchange for the Procomp module.

I noticed on mine that the vacuum advance appears to have lost the diaphragm but I got rained out before having a chance to check it out with my vacuum pump.

Bogie
Question: is the Bosch part number 9222 067 021, basically an HEI module like in the GM distributor’s? Any performance difference?

I see the Bosh part has a hefty price tag of $39 plus some other places even more ($80).
 

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Discussion Starter · #11 ·
Well I stumbled into something I wasn’t looking for. It seems the ProComp/Speedmaster 7000 distributor is out of the Australian Holden and is made for them by Bosch. Here’s a link to repairing them:


Bogie
 

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Thanks Bogie, it appear the Bosh unit is doing the same function as the GM HEI module.
It would seem the two are interchangeable provided the Bosh coil (1+ ohm) is also installed with the Bosh unit same as GM “E” core coil (0.6 ohm) is used with GM HEI module. I only deduce that since the ohm’s readings differ. I could be wrong and coil ohm‘s is close enough.
 

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Discussion Starter · #13 ·
Space the final frontier, the GM module will work but it has a different shape with pins angling from angled ends where the Bosch is more rectangular with pins along the outermost edge. I haven’t tried mounting the GM 4 pin so I don’t know it it will clear the cover, humm, another project making a new umbrella for the module?

Bogie
 

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Space the final frontier, the GM module will work but it has a different shape with pins angling from angled ends where the Bosch is more rectangular with pins along the outermost edge. I haven’t tried mounting the GM 4 pin so I don’t know it it will clear the cover, humm, another project making a new umbrella for the module?

Bogie

Just a thought would you not be even better to mount module remotely on an aluminum heat sink so it is away from direct engine heat? Also if failure it would be much easier to change out. I read somewhere that two modules mounted with switches between them to facilitate ease and no down time in the event one fails. I just thought that was a clever solution to mount it under dash with switches between them. The NASCAR solution must have had an effect on this idea.
 

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Discussion Starter · #15 ·
That’s on my rather long to do list right under my “honey do” list. I picked up the GM remote module heat sink part number 10474610. I have the perfect place for it in the cab behind the glove box where the ECM once was mounted. That has it on the cab side of the firewall just a few inches from the distributor so the wire runs are short.

Bogie
 

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That’s on my rather long to do list right under my “honey do” list. I picked up the GM remote module heat sink part number 10474610. I have the perfect place for it in the cab behind the glove box where the ECM once was mounted. That has it on the cab side of the firewall just a few inches from the distributor so the wire runs are short.

Bogie

It sounds like a good idea to keep wires short. But when GM had transistor ignition back in the 60’s the wire runs were fairly long between the distributor and the TI box that was mounted on the radiator core support. But a good size gauge wire would help keep the resistance lower. I read somewhere that the current supplied to the module and coil should not drop below 12volts or else the module could run hot. Be this true or not it sounds like good advise.
 

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Discussion Starter · #17 ·
Probably not all that critical for wire lengths, the Ford guys using the Thick Film Ignition (TFI) move the module to wheel wells and beyond, they even have ready made kits. Yes the pros use duplicated ignition systems that can be switched on the run.

I just like to keep my wire runs as short as possible, in Frankenmouse I have a convenient place in the cab that is out of the weather and the engine compartment‘s heat, coolant, fumes, fuel, oil, stray ignition currents and pressure washer cleanings. In its case the unit is out of sight and unlikely to be kicked or disturbed while the glove box it is behind is less than a handful of screws from access.

Bogie
 

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Aside from the "serious" discussion , if you read this thread title , you might think , Cheez , you must have really been pissed at that guy !! LOL. ! Like my German friend says , " the English language is a tricky one "
 
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