black68gtx

I'm tuning my 6 pack setup and after doing the necessary tuning my car stalls when I put it into any gear.
I had metering jets 64 in the center carb it did it, but with the idle curb set higher it would run. I decided to change the metering jets to 63 (thinking that it was getting to much fuel).
After installing the 63's it got worse (trying to out it into gear).
I think that maybe I should had gone the other direction and put the metering jets 65 instead of the 63's.
My outboard jets are 80 at the diaphragm and 82 at the throttle.
I'm assuming the center carb is "lean".
I have good vacuum , I've tuned the outboards enough to get a good Idle and a vacuum, along with the timing set at 900 and the timing at 14 btdc
I do not have the manifold heat blocked.
What's your thoughts?

lba440

On my six pack I run 67's in the center and 84's in the secondaries. Disconnect and plug the vacuum to the end carbs and go for a drive. Check your spark plugs for color. If they are bright white it's definitely running lean. Mine had 62's in the primaries and wouldn't idle at all. Set the center carb idle screws at 1 1/2 turns out and adjust them until you hear the idle increase or using a vacuum gauge tune for the best vacuum. If the idle improves then recheck the plugs and jet accordingly. If this doesn't do the trick you may have to adjust the secondary idle screws. I got mine right without touching the secondary idle settings. Just lucky I guess. Hope this helps you out.

gtxguy

I have the same problem -- got the idle set to 1400 rpm while out of gear and it chirps the tires when I put it in gear. I bought the setup on line and assembled it myself so that could be part of the problem. It definitely runs better when I punch it so some of it is right! I guess I'll try what Iba440 said and see how it goes.

TVLynn

It's like running a mechanical fuel injection on the street. It works fine BUT you need to tune it properly like iba440 says You need to work on the center carb first.. Does it have a stock motor ?

Drag Pak

There is quite a simple solution which requires accessing the idle syphon tubes, but here is a link to some good information.


http://www.mopar1.us/6barreltips.html

My 340 x 6 (284/484 MP camshaft) would idle in gear at 350 rpm with 3 " vacuum.

moe7404

now i remember why i love carter OEM AFBs so much.

black68gtx

Since my post I've done a lot of adjusting to the center carb. Jets - 63's to 64's, power valve 6.5 to 5.5 to 3.5. My vacuum runs 17 at idle (in neutral). Rear End on jackstands, transmission in drive vacuum is @ 8.7. Still Leary about it stalling at stop lights/signs. Although, I'm wondering about the vacuum to the outboard carbs and to the distributor. I don't get a vacuum reading to either. Is there a vacuum reading if so what should it be?

black68gtx

iba440 what if anything do you have in the 440 and are you an automatic or manual?
I have a 440 with an automatic, the "purple cam" which is a P4452993 280/280 - 60 duration 474/474 lift centerline 110.
My center carb has 64's, the outboards have 80's on the diaphragm side and 82's on the throttle side. I'm about 1 1/2 turns out on the center and less then 1/2 turn on the outboards (I have the promax base plates on the outboards). thanks for your input.

black68gtx

May have found the source of the problem.

I pulled the rear carb off the other day and noticed that it rocked left to right, I didn't pay much attention to that (thinking that the gasket will take up the slack).
After all of the adjusting, I'd come up with the same results.

So I sprayed starter fluid around the base of that rear carb and found the leak.

Today, I'm taking off the carbs and putting some RTV sealant around the gaskets and putting them back on and see if this has been the problem all along.

RacerHog

Check the base of the carbs for flatness.... Flat file them back flat again and re install them with some good thick base gaskets.

RTV might get you threw the test. but I'm pretty sure that's going to come back to haunt you some-wear out on the road.

black68gtx

The base plate is flat (promax baseplate) I tried another plate just to rule out that the promax was the culprit.

I'm afraid that the base for the carbs on the manifold might be the problem.

I'm going to check that with a straight edge.