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-   -   Scooter + Mopar = LOST (https://www.racingjunk.com/forums/showthread.php?t=33422)

roadkill2 05-11-2013 09:53 AM


Originally Posted by Harbone
Scoot your pinging might be carbon build up on the pistons, those old Mopars had a tendency to crud up. Does it have an EGR valve still on it? That will make them ping too when they are bad.
Get something turn burn that carbon off, ATF or SeaFoam nice and slow through the carb will take care of it, just make sure you are in an open area cause it will smoke like crazy!

Back in the day when anything that burned gas would get Carbon Build Up if it wasn't "Blown Out" periodically, we used . . WATER . . Bump the idle up to about 750 rpm, and verrrry slowly trickle water down the carb. It'll stumble a little bit but just keep on keepin on for about 5 minutes, from one barrel of the carb to the other . . Make sure the engine is at operating temp before you start . .

Pure Old School . . .

Scooterz 05-13-2013 10:32 AM

Harb/RK no EGR. It is a regular Eldlebrock int/carb w/ elect choke. Checked vacuum line & advance... seems to operate good. I don't mind trying both ideas for carbon. It can be shifted at 1500-2K no problem & lugs like a pig... probably did not get wound out much in its life. Even w/ bigger cam, power curve is low/mid. I bet there is carbon build up... good idea.

TheYellaBrick 05-13-2013 02:25 PM

We want a field report after application of these processes ! :D :D

Just reroute your windshield washer line into the aircleaner snorkle/top and go 'BLOW out the carbon' on your local hiway !

wmeabates 05-13-2013 03:44 PM

Ping.
 
Scoot,If the other suggestions don,t fix You up try it with the advance line off and pluged.If the ping goes away, an adjustable vacuum advance or a homemade limiter should take care of it.Bill.

Scooterz 05-14-2013 08:52 AM

DD: I will report my solutions for sure. Should have more time to work it this weekend. For now, I have been driving the 68 Chevelle to work (sunny). Can I just reiterate how damn fun it is shifting the Muncie??? man I had not driven it in almost a year... what a blast. 327/4speed is good for many shi_t's & giggles... I sounded like a little school-girl going to work today!!! LOL.

Bill: I thought that if you disable the advance; it would ping more b/c the timing would be too retarded when the power/RPM rises? Or do I have that backwards??? The timing is too advanced when under mid power... right?? I also know the timing gear is advanced 4 degrees b/c of bigger cam in it. So you are saying it is getting too much timing too fast under mid power... that makes sense too.

wmeabates 05-14-2013 10:07 AM

Scoot,Part throttle is when the vacuum will advance the timing the most when connected to the vacumm port above the throttle plate.Throttle closed little or no vacuum,part throttle high vacuum,full throttle little or no vacuum.If anyone can explain this a little more understandable give it a shot.Bill.

TheYellaBrick 05-14-2013 03:16 PM

PUT A MOPAR IN IT ! ......WAIT it IS a Mopar ! :shock: :roll: :oops: :oops: :oops: :oops:

Scooterz 05-15-2013 10:40 AM

HAA!!! Scooter is adapting to Mopar some now.

Okay Bill tell me if you think I get this right... I just get confused about vacuum sometimes & how it all flows. Basically- if the advance is advancing too fast/too soon, I get the pinging at mid range until the motor catches up w/ the timing advance.... Right? So if I temporarily plug advance & note the diff; that will tell me if the timing advance was exceeding the power curve... hence the pinging.

wmeabates 05-15-2013 03:41 PM

Scoot,Yes You said what I think might be the reason for the ping,much better than I could get it in writing also.Now about the cam being advanced.The dist.is driven by the cam but adjusted to the crank at the damper,so if set to the same degree as the befor the change, that will still be the same.Don't mean it's right just the same.Now advancing the cam does close the intake valve sooner causing a little more cyl pressure at low to mid rpm which could add to Your problem.Cyl.pressure at high rpm will be how well the cylinders are filling,V E.I think it's time for a beer now.Bill.


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