Only runs 40 Degrees advanced

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Garrett Ellison said:
It wouldn’t be a rich mixture that would cause this issue, it would be a very lean mixture. Much like at cruise rpm when the cylinder charge gets diluted by exhaust and the carburetor is just off idle and it eats up to 52 degrees of mechanical and vacuum advance. But, if it were this lean, it would have a tendency to overheat. It sounds more like a vacuum leak or more likely that changing the sniper to not control the distributor has caused an unseen change in the fuel delivery curve. I would like to hear more specifics of the build, though. Displacement, camshaft type, static compression, etc.
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Engine specifics were in earlier post but it is a 360 I rebuilt years ago it’s always been just a cruise in car so it doesn’t have that many miles. It has a whiplash Cam flat tappet MSD pro billet distributor at the moment with six AL box and matching coil has been running really good until this distributor got jammed. I was on the first day of the power tour I had ran almost 800 miles that day to get to the starting point I had just put in an a500 before I left that was really making the highway travel great
Garrett Ellison said:
But along those lines, I take it you are using an MSD timing light for the multiple spark discharge?
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I am using a new timing light that says it can do both it seems accurate no dial back I set the motor to 15° by setting the balancer and then locking down the rotor right on the terminal then cranked it without fuel and watched it with the timing light and read 15° on the balancer but when I tried to start it. it would not hit At all until I turn distributor way up 35 -40° it starts and idles doesn’t overheat I can Revit up but you can tell it’s missing a little bit when you raise the idle up because it’s too advanced but for some reason that’s the only way it will run. if I try to lower the timing back down while it’s running it will stumble and die
 
mr65cuda said:
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Engine specifics were in earlier post but it is a 360 I rebuilt years ago it’s always been just a cruise in car so it doesn’t have that many miles. It has a whiplash Cam flat tappet MSD pro billet distributor at the moment with six AL box and matching coil has been running really good until this distributor got jammed. I was on the first day of the power tour I had ran almost 800 miles that day to get to the starting point I had just put in an a500 before I left that was really making the highway travel great

I am using a new timing light that says it can do both it seems accurate no dial back I set the motor to 15° by setting the balancer and then locking down the rotor right on the terminal then cranked it without fuel and watched it with the timing light and read 15° on the balancer but when I tried to start it. it would not hit At all until I turn distributor way up 35 -40° it starts and idles doesn’t overheat I can Revit up but you can tell it’s missing a little bit when you raise the idle up because it’s too advanced but for some reason that’s the only way it will run. if I try to lower the timing back down while it’s running it will stumble and die
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I dig that car---
A little outa line but I gotta ask here , Whats the diff in an MSD light ?
I have had MSD`s on 5 diff. engines/ 4 diff. cars, and have never used any special timing light . All have run good to perfect . ?????
Selling hype by MSD ???
 
Just throwing something out here, I know on my FiTech there is a different setting in the controls for timing. Depending on the whether your using timing control or not. Maybe it wasn’t switched back to the non timing control setting? Like I said just throwing it out there.
 
famous bob said:
I dig that car---
A little outa line but I gotta ask here , Whats the diff in an MSD light ?
I have had MSD`s on 5 diff. engines/ 4 diff. cars, and have never used any special timing light . All have run good to perfect . ?????
Selling hype by MSD ???
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Any timing light made by a reputable manufacturer these days will work with modern ignition systems.
 
Wow ok so you have basically eliminated most everything except cam timming so I'm going out on a limb here but is it possible your cam "twisted" when the dist locked up and now some of the cylinders are out of phase? do you have a old junk cam and lifters around you could throw in just to see if it made a difference?
 
Did you set up the centrif. advance per the MSD instructions? Got the right springs in there for the right curve, and the right amount of total advance for the motor?
 
mod5v said:
Wow ok so you have basically eliminated most everything except cam timming so I'm going out on a limb here but is it possible your cam "twisted" when the dist locked up and now some of the cylinders are out of phase? do you have a old junk cam and lifters around you could throw in just to see if it made a difference?
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Cams don't twist, they break. The gear would strip or the little drive shaft would shear well before the cam would ever get damaged!
 
famous bob said:
I dig that car---
A little outa line but I gotta ask here , Whats the diff in an MSD light ?
I have had MSD`s on 5 diff. engines/ 4 diff. cars, and have never used any special timing light . All have run good to perfect . ?????
Selling hype by MSD ???
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You know I can’t answer that because I had an old chrome craftsman timing light for 30 years that worked on everything I ever tried it on including this MSD set up. The reason I have a new one as I had to buy a timing light while I was on this trip stuck in Charlotte I didn’t expect to do timing while I was on the trip. So that’s why I have this new one The theory is the MSD box throws out three sparks each time under 3000 RPM and I have made videos that prove that so they say that confuses some timing lights I have not personally experienced that but I’ve heard that many times
 
69_340_GTS said:
Did you set up the centrif. advance per the MSD instructions? Got the right springs in there for the right curve, and the right amount of total advance for the motor?
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I put back in the weights and springs I was using before I put the sniper unit on. It was working with this combo before but even if it wasn’t right the car would still run. I did have this locked out to use with timing control on the sniper but I reverse that to test for this situation
 
69_340_GTS said:
Cams don't twist, they break. The gear would strip or the little drive shaft would shear well before the cam would ever get damaged!
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I agree I thought about that but cams don’t twist they are so hard they are brittle they Either wear lobes down or they break. And I thought maybe it shared a key in the keyway so that’s why I pulled the timing cover off to check those but they were still aligned.
 
mr65cuda said:
I agree I thought about that but cams don’t twist they are so hard they are brittle they Either wear lobes down or they break. And I thought maybe it shared a key in the keyway so that’s why I pulled the timing cover off to check those but they were still aligned.
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Still sounds like a timing issue to me > no help tho ---
 
mr65cuda said:
Doesn’t appear to be fuel because the sniper is still in complete control of the fuel and air it shows AFR that is in line with where it should be. It is trying to balance the idle at the normal setting of about 800 and the map sensor which is similar to vacuum is about the same as before. To put a carburetor in I would have to have a regulator plumbed in somehow. So I do not suspect fuel because I can read the AFR it is in the timing somehow I have compression I have fuel I just have spark at the wrong time somehow
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Put the A/F meter away and look at the plugs. The A/F meter can throw you off.

And never tune with the A/F meter to a number. They don't all read the same.
 
I think yellowrose is probably dead on here. There is only so many times you can check the cam and distributor timing out and confirm everything is correct. Going to have to look more closely at that EFI system. Being that it was on power tour, I would be inclined to check the fuel filters out first. It’s all too easy to get a load of gacked up gasoline when your out on the road, a newly built service station is always the worst to get water from. It may just be an incredibly unlucky draw on the scale of a drag week event instead of the more leisurely power tour. Just hoping for the best at this point, I cannot even imagine the frustration this one has caused.
 
Garrett Ellison said:
I think yellowrose is probably dead on here. There is only so many times you can check the cam and distributor timing out and confirm everything is correct. Going to have to look more closely at that EFI system. Being that it was on power tour, I would be inclined to check the fuel filters out first. It’s all too easy to get a load of gacked up gasoline when your out on the road, a newly built service station is always the worst to get water from. It may just be an incredibly unlucky draw on the scale of a drag week event instead of the more leisurely power tour. Just hoping for the best at this point, I cannot even imagine the frustration this one has caused.
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I had a buddy over today that as a retired factory mechanic and used to run a speed shop and has rebuilt hundreds of Mopar‘s. We changed all kinds of settings but nothing helped if you try to dial it down less than 20° advance it dies and will not restart you crank it back up to 35 or so it will start and run good so it’s not to fuel injection Something in the Kam and timing is off no matter what we do. So I’m probably gonna tear the motor apart and try to find it.
 
Dumb question maybe, but are you absolutely certain that you don't have the new distributors 180 degrees off now? Maybe that's why it will only fire once you turn it 40 degrees...
 
I really hate that your having that much trouble with it, that is a really nice looking car, and hoping for an easy solution. I am curious as to what it is, I can't imagine what would be damaged with compression readings that good. I imagine it's a healthy combination when it's doing what its supposed to.
 
MobileCustoms said:
Dumb question maybe, but are you absolutely certain that you don't have the new distributors 180 degrees off now? Maybe that's why it will only fire once you turn it 40 degrees...
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That does not matter, it would never even start if it's more than 45° off (1 whole cylinder).
I would not tear the engine apart. You can easily verify TDC on the damper with a simple piston stop. If the damper is wrong, my guess is the ring slipped. You already verified the cam timing gears are on correctly. Plus it ran good before, and that is nearly impossible to change unless it jumped a tooth or the chain is somehow damaged, or one of the woodruff keys broke. But you already verified all that is O.K., right? So what has changed? The distributor, or the EFI. You have tried a couple different distributors, and nothing gets any better. You did change some settings in the EFI, I guess? That would be the 1st place I'd look at very carefully.
 
mr65cuda said:
I had a buddy over today that as a retired factory mechanic and used to run a speed shop and has rebuilt hundreds of Mopar‘s. We changed all kinds of settings but nothing helped if you try to dial it down less than 20° advance it dies and will not restart you crank it back up to 35 or so it will start and run good so it’s not to fuel injection Something in the Kam and timing is off no matter what we do. So I’m probably gonna tear the motor apart and try to find it.
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I would not tear the engine apart until I tried a different harmonic balancer.
None of this makes any sense, something has slipped and is no longer within it's specification.
IMO all of this points to the timing marks being in the wrong place at the right time.
Good luck
 
69_340_GTS said:
That does not matter, it would never even start if it's more than 45° off (1 whole cylinder).
I would not tear the engine apart. You can easily verify TDC on the damper with a simple piston stop. If the damper is wrong, my guess is the ring slipped. You already verified the cam timing gears are on correctly. Plus it ran good before, and that is nearly impossible to change unless it jumped a tooth or the chain is somehow damaged, or one of the woodruff keys broke. But you already verified all that is O.K., right? So what has changed? The distributor, or the EFI. You have tried a couple different distributors, and nothing gets any better. You did change some settings in the EFI, I guess? That would be the 1st place I'd look at very carefully.
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Well the damper isn’t that old and I did verify it when I had the Timing cover off I also pulled the intake and one head and also verified the number one was TDC On the damper. The fuel injection isn’t doing anything now except acting like a carburetor when you turn the timing up it starts up immediately and runs but it’s weak like if you drop it into gear it will just die. But sounds good running I had a very experienced mechanic over today and we went through everything again and he said he doesn’t have any idea what it is his best guess is the timing gear is one tooth off but we couldn’t come up with anything else. I’m going to have to pull it apart it’s no good to me like this.
 
Garrett Ellison said:
I really hate that your having that much trouble with it, that is a really nice looking car, and hoping for an easy solution. I am curious as to what it is, I can't imagine what would be damaged with compression readings that good. I imagine it's a healthy combination when it's doing what its supposed to.
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Yes it ran really good before the distributor shaft got bent it still sounds good when it starts but it’s so out of whack. Everybody agree somethings wrong just can’t figure out what it is
 
There is a polarity of the distributor sensor wires. If you have them reversed, it will be AFU. The distributor trigger will be between the reluctor teeth, and the phasing at the cap between terminals.
A correct trigger at distributor happens as reluctor tooth is passing off pickup nub.

A quick check, rotate crank to 40 deg, look in distributor to see pickup nub in relation to reluctor teeth, if not near tooth...polarity is wrong. Fix that, re-time with static setting. Set crank to 13 btdc, rotor at #1, rotate distributor, so as crank just passes 13, the reluctor tooth 1/2 off pick up nub. Tighten hold down. Crank it up, use the light, it should be within 1 to 2 degrees of desired setting.
 
Wow, it always is the simple things that come up to bite you. That reminds me of my kitchen table re-curve when I put the reluctor in upside down (like for a big block) by accident. I had a spare distributor handy so I was able to correct it quickly, but it wouldn't run for crap either. I haven't been able to run an MSD yet, so I will keep this in mind!
 
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