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tech carb and ignition

Cornpatch MO

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440 engine , Holley 750 , double pump, mechanical secondary. Edelbrock RPM performer.
.475 lift- long duration cam .. Stock points distributor. 4 speed trans. 3:55 rear gears
I think I have my Holley set up about right. Throttle response at idle is quick and crisp. Wing it and instant RPM, no hesitation.
For now, I am keeping the rebuilt points dist. It is set up for a stock 413 engine . I haven't actually checked my timeing yet. Just set it by what starts and works good. In order of importance, I would like info on what to do with my dist., to get more performance. Thanks for your input..........................MO
 
IMO a really good $$ per $$ investment is an electronic distributor and control box. Lots of good options out there. I used the old "Blue Box" before going to an early MSD 404BC. The blue box had no rev control & would easily run past 7000 RPM (which you want to avoid). The reliability of the electronic system pays off pretty quick in points replacement & time. Get a timing tape on the damper and check the total timing. My guess is 32* or so would be fine. Lots of other guys on here have much more experience with your type combo. See what they say. Time spent on tat old distrib is basically wasted.
 
i don't think you can do much with points other than change the curve and set the dwell. a good point set-up is ok but is on the decline as soon as it fires up. i'm not an MSD guy but if you ever go that way buy the whole system. i like the inductive factory type systems for my cars. they're simple, easy to maintain, and if by chance you have a problem on the road parts swap is very simple. i have one of the FBBO boxes with the rev limiter on one of my cars and really like it. it gives me a full 12 volts to the coil without all the stand offs at the coil and if by chance it fails i can just plug in a cheap box and drive home.
 
Steve,
Try to find a shop with a distributor machine, but you can do this on the car with a timing light (takes longer). Then, increase the speed of advance (mechanical) to bring in full advance by 2500-2800 RPM (remove the heavy spring or obtain lighter tension units). Mopar "bibles" call for 38* total and you can mark that on the damper to make reading easier (divide damper circumference by 360 and multiply that number by 38 to obtain the distance from the factory damper groove-assuming it is marked correctly). I would use 10-15* initial advance and limit mechanical advance to the 38* total. You will have to weld or braze one advance slot to shorten weight travel to accomplish this. If you would like to run the vacuum advance to maintain fuel mileage, some of the OEM vacuum canisters can be adjusted with a "allen" wrench. This will change timing on when the vacuum advance comes into play. The canisters' linkage has a number stamped in corresponding to degrees of advance it will provide. Use a "ported" vacuum source.
This is what we did in the old days! And it's cheap!
Mike
 
You will get A LOT of opinions. Swap to electronic ignition FOR SURE (whatever you can afford). Especially since you have a 4spd, try to get one with a rev-limiter (like a MSD-6AL or similar). A stock '72+ Mopar ignition system (no rev limiter) would definitely be an improvement & there are tons of better/more expensive options, but go electronic for sure.
 
440 engine , Holley 750 , double pump, mechanical secondary. Edelbrock RPM performer.
.475 lift- long duration cam .. Stock points distributor. 4 speed trans. 3:55 rear gears
I think I have my Holley set up about right. Throttle response at idle is quick and crisp. Wing it and instant RPM, no hesitation.
For now, I am keeping the rebuilt points dist. It is set up for a stock 413 engine . I haven't actually checked my timeing yet. Just set it by what starts and works good. In order of importance, I would like info on what to do with my dist., to get more performance. Thanks for your input..........................MO

Here's the best bang for the buck unless you need to follow the MSD crowd:

https://www.summitracing.com/int/parts/sum-850420/overview/make/chrysler

https://www.summitracing.com/int/parts/sum-850500

Simple to install, high output, reliable and they're built by Firecore ( the people who bring you the best ignition wire sets bar none).
 
I'm going to recommend the Pertronix Ignitor III and Flamethrower III coil. I have one in my GTX and I have had zero issue. You put the plate in the old distributor and the only non factory look is an extra wire coming from the distributor. It has an easy to set rev limiter built in. Also, with this setup you can bypass the ballast resistor so one less thing to go wrong.

I have been running a Pertronix II in my 62 for going on two years without issue as well.
 
IMO a really good $$ per $$ investment is an electronic distributor and control box. Lots of good options out there. I used the old "Blue Box" before going to an early MSD 404BC. The blue box had no rev control & would easily run past 7000 RPM (which you want to avoid). The reliability of the electronic system pays off pretty quick in points replacement & time. Get a timing tape on the damper and check the total timing. My guess is 32* or so would be fine. Lots of other guys on here have much more experience with your type combo. See what they say. Time spent on tat old distrib is basically wasted.
Thanks for your input, but I am a little resistant to electronic ignition on this car. It is built to look old school , so I don't want a box. On down the road I am thinking Pertronix III points conversion. But for now, I want to play with the stock distributor , even if it is not dual point. .......................................MO
 
i don't think you can do much with points other than change the curve and set the dwell. a good point set-up is ok but is on the decline as soon as it fires up. i'm not an MSD guy but if you ever go that way buy the whole system. i like the inductive factory type systems for my cars. they're simple, easy to maintain, and if by chance you have a problem on the road parts swap is very simple. i have one of the FBBO boxes with the rev limiter on one of my cars and really like it. it gives me a full 12 volts to the coil without all the stand offs at the coil and if by chance it fails i can just plug in a cheap box and drive home.
FBBO box?? Thanks for your input.....................MO
 
Steve,
Try to find a shop with a distributor machine, but you can do this on the car with a timing light (takes longer). Then, increase the speed of advance (mechanical) to bring in full advance by 2500-2800 RPM (remove the heavy spring or obtain lighter tension units). Mopar "bibles" call for 38* total and you can mark that on the damper to make reading easier (divide damper circumference by 360 and multiply that number by 38 to obtain the distance from the factory damper groove-assuming it is marked correctly). I would use 10-15* initial advance and limit mechanical advance to the 38* total. You will have to weld or braze one advance slot to shorten weight travel to accomplish this. If you would like to run the vacuum advance to maintain fuel mileage, some of the OEM vacuum canisters can be adjusted with a "allen" wrench. This will change timing on when the vacuum advance comes into play. The canisters' linkage has a number stamped in corresponding to degrees of advance it will provide. Use a "ported" vacuum source.
This is what we did in the old days! And it's cheap!
Mike
Ahhh, perfect--the info I was looking for. We call the " old days" --"old school" now , and that is why ole Brutus has " FLASHBACK" on the sides. LOL. I do have access to a dist machine.
Can you tell me why( theory) a lot of advance, and a quick advance helps performance? On this car, fuel millage is not a consideration , and so no vacume advance used. ....Thanks Mike.......................MO
 
You will get A LOT of opinions. Swap to electronic ignition FOR SURE (whatever you can afford). Especially since you have a 4spd, try to get one with a rev-limiter (like a MSD-6AL or similar). A stock '72+ Mopar ignition system (no rev limiter) would definitely be an improvement & there are tons of better/more expensive options, but go electronic for sure.
I welcome all opinions. Thank you................................MO
 
I'm going to recommend the Pertronix Ignitor III and Flamethrower III coil. I have one in my GTX and I have had zero issue. You put the plate in the old distributor and the only non factory look is an extra wire coming from the distributor. It has an easy to set rev limiter built in. Also, with this setup you can bypass the ballast resistor so one less thing to go wrong.

I have been running a Pertronix II in my 62 for going on two years without issue as well.
That is exactly my plan a little ways down the road. I had the Pertronix I and the coil in my old 56 Chrysler 354 Hemi and am absolutly sold on it. Does the III do everything as advertised , such as rev limiter and other features? Thanks for your reply.................................MO
 
Ahhh, perfect--the info I was looking for. We call the " old days" --"old school" now , and that is why ole Brutus has " FLASHBACK" on the sides. LOL. I do have access to a dist machine.
Can you tell me why( theory) a lot of advance, and a quick advance helps performance? On this car, fuel millage is not a consideration , and so no vacume advance used. ....Thanks Mike.......................MO
Well, this is pretty involved but to simplify: the air/fuel mixture when ignited burns away from the spark like a grass fire moves with wind. As RPM rises the fire still has to burn across the combustion chamber but, less time is available for the process so the fire is started earlier to compensate. There is a point when combustion will fight against engine rotation so advance can't be a limitless function. As we improve engine efficiency the need for other than OEM advance curves become necessary for optimum power and torque.
Chrysler determined their big blocks worked best with iron heads at 38* total advance but that number varies a little. With Edelbrock RPM small chamber heads my 493 likes 35* total. The lower numbers indicate a more efficient combustion process. Many sources are out there for a more complete explanation.
Mike
 
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