I rebuilt my 6 pack carbs with some of pro max parts today

[Moparal]

I already had 3 new rebuild kits on the shelf, plenty of cleaner, and a lot of idle time. So I dove into the carbs today. The carbs already work good, I just wanted to install the promax outboard plates to give them a try.

I went with the blue non stick gaskets and also the nylon seals to help with jetting up and down, till I find what works best in jetting them.

I took out the Mopar Pweformance race kit I had just installed 2 months ago. It really woke the car up as it was. I ended up installing #81 jets in the front carb  #64 in the center carb with a 4.5 power valve and a #31 squirter, then installed #82 jets in the back carb.


Once installed, it fired right up, I let the engine get up to temp before making adjustments,  Carries a good lopety sound out the back now at around 900 rpms and doesnt burn my eyes as bad as it did before. The throttle response was right on with no hesitation or bog when I twisted it up. The squirter pump cam adjustment seemed to working best at  .015 thou.  The job took me about 6hrs to complete. Most of it involved cleaning. I can hear the difference and feel the difference in the change i just did.  So now om moving on into another area of the car to tinker with it since im home for 5 weeks. 

[nqkjw]

What's the reasoning behind one jet size bigger in the rear carb?

[6packCuda]

I also used the ProMax rebuild kit and outboard jet plates in mine and have been very happy with it.

[Supercuda]

 I would have thought that the bigger jet would wind up in the front carb. Sometimes, you just have to try it first, I guess. What is the reference to the pump cam adjustment? The clearance is just to avoid bottoming out the arm in the check ball at WOT. Are you dialing in some hesitation in the pump circuit?

[Moparal]

When I went to the Indy swap meet to buy the kits, I talked with Promax people for a while. Thwy wanted me to install 78's in front 63 in the middle and 86 in the rear. When I went online and read an article from Muscle car, they went 84 front and rear and 66 center. I wanted to start some where close with the jets I had on hand is all. So I left the front jets a little smaller so I could get to them easier was all.  The 15 tho on the squirter was to allow for idle settings at initial start up.I have never owned a carb where the idle screw wasnt being used at all with no pressure on the throttle. Once i started the engine and adjusted the idle, the setting now is close to zero, just toutching the pump arm. So right when you touch the throttle, the pump starts working.

I took #67 jets out of the center carb that was installed with my Direct connection kit. That kit wanted a 69 jet in the center carb which I feared would be to rich for my engine combo on the street.  So actually, I just put jets in from what I had on hand as a starting point

[6packCuda]

I'm running #84s in both outboard carbs and a #66 in the center and a 3.5 power valve. I ran it up to 5500 rpm on a Mustang dyno and maintained a 13.00 A/F ratio with this setup.

[Moparal]

After running through the valves again today, I took the car out for a spin, and yeah it spun   Without track time or a dyno, I will most likely stay where im at on the jets for now. I don't feel like milking everything out of it since I dont drive it much. I was also trying out my new tune up so I could run on 92 octane. It was 88 here todat and I had no pings in the engine and it never went over 185 on water temp, so I know I'm close.

[Supercuda]

Too cool. Maybe you should go with a smaller jet in back, to match the front? These kinds of tuning decisions are always difficult, when everything seems to run so well. I've found that patience and driving are the most fun way to determine which is better, the bigger in rear, or smaller jet in front. Sounds like it won't make a huge difference, either way. Interesting way to set up the carb, undoing the pump adjustment until you have he idle set. I never worried about the pump arm adjustment until I had the basics set. As long as it touches the arm on idle, and doesn't bottom out at WOT, it's all good.