Too much timing?

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Ok 2 years later and im still working on this. So here's what I've done and where I'm at. The car is tagged now so I'm driving it more and actually getting seat of the pants testing done instead of gauges and numbers. The distributor is a pro form style so the fbo plate didn't help at all instead you adjust the total or lock out using a set screw. So I got the initial set at 14 total 34. All in by 3000. Without the vacuum advance. With the vacuum advance hooked up total is 51. Seems like alot to me but its running good. So one thing I've noticed when I floor it at a dead stop or even rolling it bogs and occasionally it will backfire thru the carb sounds like a lean pop to me. (May be wrong) so I messed the timing again I dropped the total to 44 with the vacuum hooked it dropped the initial to 7. Ran it and it's a dog! Wouldn't even spin the tires. So I bumped it back up to the original set up at the beginning of this thread 24 initial 44 total and unhooked the vacuum and it runs awesome. Can't keep it in the road does nothing but spin! Lol but at WOT I'm still getting the lean pop and bog. So I kept digging pulled the plugs and bt reading the plugs im seeing thats its too rich. Black sooty plugs. So im thinking it's in my air flap on the Thermoquad not opening fast enough. So now for the questions. Do yall think it's a fair assessment that the bog at WOT is the air flap causing a lean condition at WOT? With the plugs showing rich Should I try to lean the carb and adjust the air flap to open sooner? Or leave the mixture as is and adjust the air flap and test it? I dont wanna start chasing my tail here. I know i probably should change one thing at a time. Is 51 total with the vacuum advance way too much? it seems alot to me. I have the distributor curved for total at 34 and to be all in at 3000 rpm but with the vacuum advance hooked up apparently I have 17-18 in the can. Should I limit the total based off the can or let it be? If my total should be a max of 36 I could lock the distributor at 18 and have 36 total just using the can. Im I thinking to much into it? As far as I can tell even with the 51 total im not getting any detonation (unless the what I think is a bog/lean pop is indeed detonation).
 
dartfreak75 said:
Ok 2 years later and im still working on this. So here's what I've done and where I'm at. The car is tagged now so I'm driving it more and actually getting seat of the pants testing done instead of gauges and numbers. The distributor is a pro form style so the fbo plate didn't help at all instead you adjust the total or lock out using a set screw. So I got the initial set at 14 total 34. All in by 3000. Without the vacuum advance. With the vacuum advance hooked up total is 51. Seems like alot to me but its running good. So one thing I've noticed when I floor it at a dead stop or even rolling it bogs and occasionally it will backfire thru the carb sounds like a lean pop to me. (May be wrong) so I messed the timing again I dropped the total to 44 with the vacuum hooked it dropped the initial to 7. Ran it and it's a dog! Wouldn't even spin the tires. So I bumped it back up to the original set up at the beginning of this thread 24 initial 44 total and unhooked the vacuum and it runs awesome. Can't keep it in the road does nothing but spin! Lol but at WOT I'm still getting the lean pop and bog. So I kept digging pulled the plugs and bt reading the plugs im seeing thats its too rich. Black sooty plugs. So im thinking it's in my air flap on the Thermoquad not opening fast enough. So now for the questions. Do yall think it's a fair assessment that the bog at WOT is the air flap causing a lean condition at WOT? With the plugs showing rich Should I try to lean the carb and adjust the air flap to open sooner? Or leave the mixture as is and adjust the air flap and test it? I dont wanna start chasing my tail here. I know i probably should change one thing at a time. Is 51 total with the vacuum advance way too much? it seems alot to me. I have the distributor curved for total at 34 and to be all in at 3000 rpm but with the vacuum advance hooked up apparently I have 17-18 in the can. Should I limit the total based off the can or let it be? If my total should be a max of 36 I could lock the distributor at 18 and have 36 total just using the can. Im I thinking to much into it? As far as I can tell even with the 51 total im not getting any detonation (unless the what I think is a bog/lean pop is indeed detonation).
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@Bewy is our TQ expert! Maybe he'll chime in
 
You need to adjust the air door so that it does not open so much. That will richen it up some. And possibly tighten up the air door spring. I would adjust the door a tad less open first.
 
RustyRatRod said:
You need to adjust the air door so that it does not open so much. That will richen it up some. And possibly tighten up the air door spring. I would adjust the door a tad less open first.
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Ok so I was thinking about it backwards. It needs to open less to make it richer! That makes sense. Do you think that's the problem?
 
dartfreak75 said:
Ok so I was thinking about it backwards. It needs to open less to make it richer! That makes sense. Do you think that's the problem?
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If it bogs or hesitates going into the secondaries like you describe, it surely could be. Do you know how to limit the door's opening? There is a "tang" cut into the secondary door on the driver's side. There is a stationery tang on that side as well. You may also need to adjust the spring tension, too. It's usually a juggle between the two. Here is how to adjust the air door opening. See the bent tang on the door the red arrow is pointing to? That's how to adjust how far the door opens and make changes in the secondary overall mixture. You "may" need to bend yours so that it doesn't open as far as the door in this picture. You just need to kinda play around with it. Maybe adjust the door "a little" less open. Drive it. Come back and tighten the spring a little. Drive it. Rinse and repeat. Do you have the secondary spring adjusting tool?
THERMOQUAD.jpg
 
RustyRatRod said:
If it bogs or hesitates going into the secondaries like you describe, it surely could be. Do you know how to limit the door's opening? There is a "tang" cut into the secondary door on the driver's side. There is a stationery tang on that side as well. You may also need to adjust the spring tension, too. It's usually a juggle between the two. Here is how to adjust the air door opening. See the bent tang on the door the red arrow is pointing to? That's how to adjust how far the door opens and make changes in the secondary overall mixture. You "may" need to bend yours so that it doesn't open as far as the door in this picture. You just need to kinda play around with it. Maybe adjust the door "a little" less open. Drive it. Come back and tighten the spring a little. Drive it. Rinse and repeat. Do you have the secondary spring adjusting tool?
View attachment 1716138040
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I don't have a tool. I wish I did. I will use two screws drivers I did know how to bent that tab to adjust the flap!
 
Congrats on using the best 4bbl, the TQ!!

[1] Lean backfire could be sec jets too small OR pri jets too small. It just depends where exactly in the pedal movement/rpm you get the backfire. Try going to about 3/4 throttle [ not full WOT ]. If no backfire, probably needs bigger sec jets.
[2] To richen the secs overall, tighten the AV. Go to about 2.5-3 turns. You do not need a special tool [ sure helps! ], just the right size screwdriver.
[3] Ign timing. So much confusion about this. At cruise, with the centri adv inside the dist fully deployed, total timing can be 45-55* & sometimes as much as 60*. This is comprised of initial + centri + vac adv. Is the VA manifold or ported sourced? When you go to WOT, VA goes to zero.
 
Bewy said:
Congrats on using the best 4bbl, the TQ!!

[1] Lean backfire could be sec jets too small OR pri jets too small. It just depends where exactly in the pedal movement/rpm you get the backfire. Try going to about 3/4 throttle [ not full WOT ]. If no backfire, probably needs bigger sec jets.
[2] To richen the secs overall, tighten the AV. Go to about 2.5-3 turns. You do not need a special tool [ sure helps! ], just the right size screwdriver.
[3] Ign timing. So much confusion about this. At cruise, with the centri adv inside the dist fully deployed, total timing can be 45-55* & sometimes as much as 60*. This is comprised of initial + centri + vac adv. Is the VA manifold or ported sourced? When you go to WOT, VA goes to zero.
Click to expand...
Thanks bud! I'm glad you chimed in! I have not noticed any backfiring at 3/4 throttle. I will test some more on my next outing and pay more attention to it. I have noticed some backfire when you rev it up in park. I'll test it some more as is and then tighten the air flap and test some more and report back. As for the timing it is ported vacuum plugged in the carb. I think I'm just gonna reduce the total back down to 34 with the initial at 20 something it seems to really like that range. I have good vacuum starts idles and runs great.
 
It should not backfire at any rpm. I image revving it in P you are only opening the primaries. There is no real load on the engine in P, so the b/firing is probably sooty plugs. The plugs should be a 5 heat range in NGK, [ not colder if that is what you have been told ].
What ign system?
 
Bewy said:
It should not backfire at any rpm. I image revving it in P you are only opening the primaries. There is no real load on the engine in P, so the b/firing is probably sooty plugs. The plugs should be a 5 heat range in NGK, [ not colder if that is what you have been told ].
What ign system?
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I do have sooty plugs I pulled them out and cleaned them the other day when I was checking the timing again I'll have to check the heat range they are champions
 
Bewy said:
It should not backfire at any rpm. I image revving it in P you are only opening the primaries. There is no real load on the engine in P, so the b/firing is probably sooty plugs. The plugs should be a 5 heat range in NGK, [ not colder if that is what you have been told ].
What ign system?
Click to expand...
Oh the ignition system is a stock factory mopar ecu with the mp orange box
 
My plugs are champion Rc12yc, so a 12 heat range. Not sure how they compare to ngk heat range scale?
 
Sometimes a cleaned plug doesn’t come back to full performance. I run cheap autolites just so I can throw new plugs in Willy Nilly and not cry.
 
If the plugs are sooty, that might be a sign that it needs more initial timing.
 
furrystump said:
Sometimes a cleaned plug doesn’t come back to full performance. I run cheap autolites just so I can throw new plugs in Willy Nilly and not cry.
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Yea I plan on replacing them very soon. I think I may go with ngks this time alot of guys seem to use them gotta be a for a reason.
 
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