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Msd old school box question

Pat70rr

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So my buddy sold his Mopar and came by with some extra stuff he had in his garage one thing that grabbed my attention was this don't know much about it but he said it worked ... Curious to see if anyone here is or has run one ? I'm currently running a chrome box , mp distributor ,and a Accel super stock coil 8140 was thinking of plugging it in for kicks , any information would be greatly appreciated
Thanks in advance , Pat
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Why fix what aint broken.
I believe that is an early MSD unit no rpm limiter or such so no point messing around.
 
Pat,
Did you receive any installation/hook-up information. Do you have the Mopar reluctor distributor (aka "dizzy") or MSD fistributor to trigger the box? In case it does not work, I've been told that MSD csn repair them...for a fee.
I once had a REALLY OLD MSD 6C box (with the 5 prong Mopar connector plug), that I could not wait to remove it and install an origional numbers matching Prestolite dual point distributor for my RS23V0A***** GTX. But there are many guys that prefer the MSD system.....you pay your money and take your choice.... Just my opinion of course.
BOB RENTON
 
Pat,
Did you receive any installation/hook-up information. Do you have the Mopar reluctor distributor (aka "dizzy") or MSD fistributor to trigger the box? In case it does not work, I've been told that MSD csn repair them...for a fee.
I once had a REALLY OLD MSD 6C box (with the 5 prong Mopar connector plug), that I could not wait to remove it and install an origional numbers matching Prestolite dual point distributor for my RS23V0A***** GTX. But there are many guys that prefer the MSD system.....you pay your money and take your choice.... Just my opinion of course.
BOB RENTON
I do have the Mopar distributor in my vehicle , but I did not get any instructions it was sitting on his shelf but he did say it worked it looks like it just gets grounded there's at ach terminal and a Mopar plug just curious to see if anybody knew of these I like the fact that it has the mopar plug no hacking the wiring for hookup
 
That is a 5C... Just unplug your regular 5 pin or 4 pin ECU and plug it in... Make sure you hook up the ground wire...

Back in 79 I bought one, had a 340 4 sod E body with 3:55 gears and a little to much cam... You had to slip the clutch quite a bit to take off or the engine would stall...

Put on the 5C, no other changes and suddenly you could damn near dump the clutch at idle & the car would chug away... Low RPM torque was night & day... The spark was hot enough that the mixture was gonna burn no if’s and’s or but’s...
 
That is a 5C... Just unplug your regular 5 pin or 4 pin ECU and plug it in... Make sure you hook up the ground wire...

Back in 79 I bought one, had a 340 4 sod E body with 3:55 gears and a little to much cam... You had to slip the clutch quite a bit to take off or the engine would stall...

Put on the 5C, no other changes and suddenly you could damn near dump the clutch at idle & the car would chug away... Low RPM torque was night & day... The spark was hot enough that the mixture was gonna burn no if’s and’s or but’s...
Thanks so much 1 Wild RT just one question I always see those ballast resistor questions with MSD 's do I bypass resistor or just leave everything as is ? Thanks again I can understand why they don't make these with the Mopar plug anymore looks so cool
 
Like I said, no other changes, the ballast can stay..
 
I do have the Mopar distributor in my vehicle , but I did not get any instructions it was sitting on his shelf but he did say it worked it looks like it just gets grounded there's at ach terminal and a Mopar plug just curious to see if anybody knew of these I like the fact that it has the mopar plug no hacking the wiring for hookup

Pat,
As I recall, the MSD box needs a switched 12 volt source, a good solid ground, the distributors pick up coil connection, and the two wires going to the coil and an MSD or compable coil. The MSD box furnishes a 400+ volts to the coil to make the high voltage spark. THE OLDER MSD BOXES REQUIRE THE USE OF THE MSD TACH ADAPTOR ACCESSORY FOR YOUR TACH TO WORK. The new models have this built in.
Perhaps the best thing you should do is call/e-mail MSD with the model # and serial # on your box and inquire about wiring diagram or harness connections...that would your best source of information. Just my opinion of course.
BOB RENTON
 
Pat,
As I recall, the MSD box needs a switched 12 volt source, a good solid ground, the distributors pick up coil connection, and the two wires going to the coil and an MSD or compable coil. The MSD box furnishes a 400+ volts to the coil to make the high voltage spark. THE OLDER MSD BOXES REQUIRE THE USE OF THE MSD TACH ADAPTOR ACCESSORY FOR YOUR TACH TO WORK. The new models have this built in.
Perhaps the best thing you should do is call/e-mail MSD with the model # and serial # on your box and inquire about wiring diagram or harness connections...that would your best source of information. Just my opinion of course.
BOB RENTON

Like I posted above, it’s a 5C, it doesn’t require any more wires other then the ECU plug and ground...

Or he can call MSD... If anyone there is old enough to remember the 5C...
 
My friend has run a 5C box in his Dart small block for decades. Car runs 10.60's with no issues.
Doug
 
My friend has run a 5C box in his Dart small block for decades. Car runs 10.60's with no issues.
Doug
As i mentioned, l had the MSD box on the GTX....removed it and installed the Prestolite dual point distributor. The old MSD box and distributor (aka "dizzy") were deposited in the "round file" without one iota of regret / remorse what so ever.
BOB RENTON
 
As i mentioned, l had the MSD box on the GTX....removed it and installed the Prestolite dual point distributor. The old MSD box and distributor (aka "dizzy") were deposited in the "round file" without one iota of regret / remorse what so ever.
BOB RENTON

Well you’re entitled to your opinion, for a stock vehicle I could see your point.. But he has the MSD, he’s not looking to compete in an OE judged event... Maybe he could just try it....

Personally I have a vehicle which originally was OE judged, but honestly that whole program bores the hell outta me & I modify anything and everything in the interests of a better running/driving vehicle...

Currently the car has bigger brakes, better suspension parts, EFI & I’m working on having Overdrive...
 
Oh yea I'm so far from original and so happy had a ton of people compliment my ride this weekend so much fun having a car your way ....... I'm actually working on it now
 
Well you’re entitled to your opinion, for a stock vehicle I could see your point.. But he has the MSD, he’s not looking to compete in an OE judged event... Maybe he could just try it....

Personally I have a vehicle which originally was OE judged, but honestly that whole program bores the hell outta me & I modify anything and everything in the interests of a better running/driving vehicle...

Currently the car has bigger brakes, better suspension parts, EFI & I’m working on having Overdrive...

Personally, it all depends on: the owner's expectations, likes & dislikes, and probably, the most governing factor, is the cost and the affordablity of what is desired. My preference is to retain as much origional appearance and function but there are several internal engine components/modifications that allow for more power and reliability. I wish you well with your vehicle and your expectations and endeavours.
BOB RENTON
 
I have a msd box so old, they weren't even using numbers yet (5c, 6a, 7al2 etc). Still works like a champ.
I believe the old stuff has a MUCH better reputation than the new stuff.
 
I have a msd box so old, they weren't even using numbers yet (5c, 6a, 7al2 etc). Still works like a champ.
I believe the old stuff has a MUCH better reputation than the new stuff.

I agree, the old stuff was mostly bulletproof.. And back then if something failed your send it in and they would fix it for free...
 
That’s the thing about an MSD they don’t do much above 2500-3000 rpms but down low they force a raggedy mixture to burn more completely
 
That’s the thing about an MSD they don’t do much above 2500-3000 rpms but down low they force a raggedy mixture to burn more completely

Perhaps they should change the name to something more appropriate. Maybe MSDS...Multiple Spark Discharge Sometimes? I realise that MSD meant Multiple Spark Discharge which l believe is a capacitor discharge system that sends a high voltage discharge to the coil's primary which in turns boosts it further. Because it takes a finite amount of time for each capacitor charge/discharge cycle, as engine RPM's (more than 2500/3000) increase there just is not enough time to do this more than once per cylinder firing. At low RPMs the multiple firings per cylinder may be to an advantage but at high RPM's this cannot occur but maybe the current MSD boxes have increased capabilities to do so.

If the intent is to have a higher voltage spark to insure the cylinder actually fires at ALL RPMs, consider using the GMs HEI MODULE (only not the total distributor) and a coil with a low resistance primary and the elimination of the failure prone Mopar ballast resistor. The GM HEI MODULE (only) mounted to an aluminium adapter plate under the Mopar electronic distributor (which triggers the GM module and is almost invisible) in conjunction with the coil will produce a 40,000+ volt spark energy pulse sent to the plugs, from low RPM thru high RPM all the time every time. Much simpler than the MSD system and at a significantly lower cost, since you already have the Mopar electronic distributor. Just another alternative to consider and just my opinion of course.
BOB RENTON
 
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