Valve float at the drag strip! I think.

[2quick]

Have you checked or logged fuel pressure and AFR on the top end? Maybe pressure getting low?
Is the issue just on the high end, or 6300 RPM even in first?

Fuel pressure is dead on 46psi and never moves. Running a billet dominator pump..

 

[dvw]

Fuel pressure is dead on 46psi and never moves. Running a billet dominator pump..

 

[dvw]

It doesn't sound like it's on the limiter. It sounds like it's got a cylinder(s) firing at the wrong time. I'd recheck the adjustable rotor. Did it ever act up with the old rotor?
Doug

 

[2quick]

It doesn't sound like it's on the limiter. It sounds like it's got a cylinder(s) firing at the wrong time. I'd recheck the adjustable rotor. Did it ever act up with the old rotor?
Doug

I don’t know. Like I said I had the limiter set to 6300 so I never really got into the popping before. I swapped the rotor due to locked out timing and I was having issues with stater kick back. I adjusted the rotor with a hole in another cap and a timing light. Looks like rotor alignment was off so I backed it off and lock it down. Thing is I still get stater kick on occasion.

 

[LemonWedge]

Yes I'm reading this as well. Seems to be a thing with a ghost REv limit on certain boxes but i"m thinking RFI has something to do with it. My Box is under my dash also but theirs a lot of other stuff there too..

I agree with Ron that the rest of the timeslip seems to be in line with the 11.0’s. Especially soft down low for the combo. This would lead me to think the advance curve may be really out of whack. Is it popping every time it gets to 6300, or only in 3rd gear?
Take Dwayne’s advice and turn off the limiter. Also, I’m sure that box has a retard function. Are you sure it’s not pulling timing out somewhere in the curve?

On the positive side: The car looks almost unfairly cool.

 

[2quick]

I agree with Ron that the rest of the timeslip seems to be in line with the 11.0’s. Especially soft down low for the combo. This would lead me to think the advance curve may be really out of whack. Is it popping every time it gets to 6300, or only in 3rd gear?
Take Dwayne’s advice and turn off the limiter. Also, I’m sure that box has a retard function. Are you sure it’s not pulling timing out somewhere in the curve?

On the positive side: The car looks almost unfairly cool.

I’m not sure of anything at this point. It does pop anytime I get near the 6500 range but I short shift the 1-2 then pops real bad trying to get through the trap. I think the car wants to trap around 6600-6700 although I can’t get it there to be sure.

 

[2quick]

This my game plan.
1. Figure out how to remove the MSD Rev limiter all together. I don’t think there is an actual on/off selection for this but maybe setting the the Rev limit number to zero will work.
2. Check rotor phasing again.
3. Separate the distributor pickup wiring from the main coil wire it currently runs along side off.
4. Also separate the pickup wire from where it goes through the fire wall in the same hole as the coil primary wiring.
5. I may even run a dedicated ground wire to the one wire alternator.

This is my plan of attack.

 

[PRHeads]

On my digital 6 box, putting the rev limiter dial at “0” turned it off.

 

[2quick]

On my digital 6 box, putting the rev limiter dial at “0” turned it off.

This is a programmable 6. There are no dials. Laptop to make changes.

 

[2quick]

Here is the navigator and then a picture of it expanded to max RPM. think if I just put in zero RPM it will turn off?

 

[33 IMP]

I think your rotor phase is probably fine, you did it right, but i think the rest of your attack should solve your problem. Crosstalk in a couple places.
Digital sixes don't like "neat" wiring much.

 

[2quick]

So it looks like the lowest I can set the Rev Limiter to is 2700, and I still don’t see a place in the tree to turn it off completely. I may need to call MSD

 

[451Mopar]

3. Separate the distributor pickup wiring from the main coil wire it currently runs along side off.
4. Also separate the pickup wire from where it goes through the fire wall in the same hole as the coil primary wiring.

If you are running a magnetic pickup signal wire along all those other wires, that is most likely the problem.

 

[PRHeads]

Prior to buying the digital 6 box I was just running the plain old analog 6a...... the one with no limiter.
Never a problem, ran it for years.
Decided I needed something more modern........ bought the digital 6, matching e-coil(to replace an ancient ACCEL super coil).
I had a couple months of trouble free operation before having issues with the limiter.
After I started running it with the dials at “0”, I moved some wires around, got the shielded pick-up wire, etc......but never re-activated the limiters to see if the problem was gone or not.
I ended up selling the digital 6 and e-coil, and bought another old analog 6a before they disappeared.
Someone gave me another used one which wouldn’t fire off the green/purple trigger wire, but worked with points off the white wire.
I sent it to MSD and they fixed it for $35.
Around the same time I was “enjoying” my digital 6 box, my friend was also enjoying his.
He replaced it with an analog 7al-2....... which has been trouble free for years.

I’m not really sold on the digital stuff.
The features are nice....... but they def seem fussier than the old analog boxes.

 

[2quick]

I spoke With MSD tech-support today and they want me to return the box. They say that in order for a problem like that to happen from RFI interference it would happen sporadically at any given rpm range. The fact that it happens only at a specific RPM or within 100 RPM of it in either direction it’s probably a short in the chip inside the box. They also said that it’s not the first time they’ve heard it .

 

[PRHeads]

My only reply to that is...... at least in my car, the limiter erroneously coming in at 5k, with the dials set to anything 5k or higher........ could not be duplicated with the msd tester.
With the tester, the limiter worked perfectly at any rpm you set it at.
With the motor actually running....... it was 5k........ whether it was set at 6k, 7k, 8k, etc.

When the problem first showed itself was in the burnout box where the motor wouldn’t rev over 5k.
I thought someone was ******* with me and had turned my limiter down.
Got back to the pits...... nope...... still set at 7200.
You could floor it in neutral..... would only go to 5k.
Moved the knobs up and down....... 5k.
I thought I was done for the day....... then thought to just turn it to zero to see what happened.
No more problem.

Next day at home, hooked up the msd tester....... rev limiter works perfect....... tried numerous settings...... all worked within 10rpm of the setting.

I unplugged everything, plugged it all back in, wiggled wires, etc...... couldn’t make it act up.
I figured...... eh, it’s a fluke.
Turned the limiter back to 7200.

Next time at the track....... I make a pass or two, no problems.
Then it started hitting the limiter at 5k again.
Put it back to “0”........problem gone.

 

[2quick]

FYI MSD also said that in order to turn off the Rev limiter completely I need to Set the value to the highest available in the software.

 

[PRHeads]

Worth a try.

 

[2quick]

Set the limiter to the limit at 12500 and it pulls straight through 7200 and feels pretty good no popping or flames. I guess that confirms it’s a Rev limit issue. Going to send box back and see if it fixes the issue.

 

[Dan64]

Set the limiter to the limit at 12500 and it pulls straight through 7200 and feels pretty good no popping or flames. I guess that confirms it’s a Rev limit issue. Going to send box back and see if it fixes the issue.

What did it run?.