I would go back to the last thing that was changed prior to this problem which was posted in your first message. The engine.

If you feel that this could still could be an “ignition problem” here’s what I suggest. Don’t replace any of the electrical components a second time that have already been changed.

Consider re-wiring the car. I know this sounds extreme. But, if it’s ignition, it could very possibly be in the wiring.

Because you lack ignition data acquisition, you’re at a loss to help you decide on making this re-wire decision.

Been there, knowing in data acquisition I had an ignition problem, replaced every electrical components to include battery, disconnect, alternator, ign ON switch, grounds. The ignition problem would not go away. Threw away the old switch box and removed all the old wiring. Installed new switch box, relay board and all new wiring and everything was fixed.

Good Luck

maybe it's the engine. You did state all is the same as last season except for the engine being freshened. Do a leak down and compression test.

quote:

Originally posted by 1320racer:
maybe it's the engine. You did state all is the same as last season except for the engine being freshened. Do a leak down and compression test.

Or maybe as most thought.
28out32numidia racer DOESN'T KNOW

lol

Turkey hunting is fun too so maybe just some time away from car to think.
Maybe if you got a buddy with a car that you could swap some of your stuff onto his car and try on his car to see if they work ok.
I would say it is ignition or electrical, fluttering is from ignition not firing for whatever reason and the popping is the unburnt fuel igniting in the pipes but that is just my thought.

Friend of mine has a msd tester he’s going to try it today and see what it may show. If nothing I guess I will look into rewiring

"Maybe it"s the Engine"

Congratulations! You are getting closer!

For a motor to fire it requires AIR, FUEL and IGNITION source. Not seeing Converter on that list. Just saying.

That makes a lot more sense when the ENGINE is missing, banging and popping to look at the engine than say Converter or tires. Stating the obvious for those oblivious to Facts and clueless to how things work.

Fact is the motor is missing because it has and electrical issue (Bad Ground, box, switch or other component or wire), Fuel issue (Carb, float, bad fuel etc) or Mechanical engine issue such as broken valve spring.

This message has been edited. Last edited by: Curly1,

quote:

Originally posted by jimmyc:
Friend of mine has a msd tester he’s going to try it today and see what it may show. If nothing I guess I will look into rewiring

I have one of those testers and do not trust them! They do not replicate the vibration or G Forces of a run.
My ignition tested perfect to 14,000 RPM but would not run in car. The car had a bad intermittent problem missing, banging and popping. Tested good, MSD said nothing was wrong with box but when I replaced it with different box it resolved the issue. Was told there is a circuit board in there and if solder cracks it will have an intermittent problem that tester may not show.

With the tester you may try to move around wiring while it is testing and listen for changes but it still can not replicate what happens while racing.

6 racers with far more experience than you stated it could be the converter if it’s not the valve springs, ignition or fuel which the OP has stated he checked all of those systems components. He had no choice but to swap converters. Now he needs to look into the engine and based on the info that was recently shared with me by someone that had an engine built by his builder, I would t be shocked to read there’s and issue with the motor.

Well, we are getting somewhere. At least we agree it is not the converter. Now we can look for real problem. Here is a hint. MOTOR is missing.

If you haven’t already, this is something inexpensive you could try electrically. Take some new #10 wire directly from the battery + / - to the ignition module pos / neg wires. Nothing but the ignition feed should be on these wires.

If you want to spend some money on an a item that you can leave installed, you could add a MSD-8830 noise filter to this wiring electrical feed.

jimmy,check the valve springs.

Stop wasting your time at the track and put it on a chassis dyno. Much easier and economical to work on it there.

You stated that the distributor has not been changed. Twice I have seen a problem with the piece that is welded to the shaft that holds the rotor.

Once was an old GM tach drive distributor and where this piece is brazed to the shaft it had come loose. It was very hard to find. Next one was an MSD distributor and the heli-arc weld holding it to the shaft was cracked all the way around. Drove us crazy for awhile. Won't take but a minute to look. Good luck, hope you find it.

Just because he checked it doesn’t mean he didn’t overlook something. Converter is something I would have overlooked.
I just sent back and MSD box that was cutting out and was told by MSD the box was fine, we will see in a couple weeks.

MSD always says its fine but the problem is gone when you get it back.

Did you use the same brand and part# for head gaskets?

I don't know all the details but a fellow racer had an issue when he tried a different brand head gasket for a rebuild. Head manufacturer told him to go back to what he was using.

Pulled heads and replaced gaskets and all was good. Granted,it could have been a different problem(intake gaskets,rotor phasing,...) but it solved his problem.

Just thought I'd add another variable

Good luck!

quote:

Originally posted by markemark:
If you haven’t already, this is something inexpensive you could try electrically. Take some new #10 wire directly from the battery + / - to the ignition module pos / neg wires. Nothing but the ignition feed should be on these wires.

If you want to spend some money on an a item that you can leave installed, you could add a MSD-8830 noise filter to this wiring electrical feed.

Could not agree more on that one. Bizarre issue i had was while cranking it over. The tach would pulse along with the shifter solenoid on the shifter. Something was activating the solenoid along with the RPM switch. Was told get the RPM activated switch away from the 6AL and install the noise filter right off the MSD. >> Cured

What type of cam drive do you have?

Does this car have a tach, if so have you disconnected it? Have you replaced the coil? I didn't read anywhere that you had. I had a similar issue and it ended up being the crank trigger. Also there have been 2 racers suggest rewiring the car,one being makemark, who obviously is very knowledgeable when it comes to msd ignition. The other being Shane Carr, a very experienced racer. I would consider rewiring. Also I worked with a guy that had a misfire every run after the first of the day. This went on for 2 or 3 weeks throwing parts at it,and then a roller lifter broke. Turns out that was his problem . And for the record I have broken a few converters and never did they cause popping and cracking. Hope you figure it out.