Pinging/Knocking/Popping

Hey all,

I had everything going great on the new 352 stroker up until Friday.
It was good and running fine, then all of a sudden on the off ramp it goes ding, ding, ping. I immediatly turn it off.

I pulled all spark plugs and there was no sign of detonation, compression checked all cylinders except one (can't get to it cause the headers). All came out to 175ish.

9:1 comp, 91 Octane, Edelbrock carb, Crane Xri ignition, timing at 8deg BTDC.

I cranked it over with no spark plugs and it cranked fast and smooth. Put in the spark plugs and it is VERY rough. Tried to fire it and it kinda backfired out of the carb.

Thanks for all the help! If I can't figure it out soon it's going in to a shop.

Maybe the chain jumped a tooth or two...


Check under the dist cap for Moisture.


FE

Any specific locations? What should I do about it?
Double roller by the way. Hyd roller cam, steel dist gear.

Maybe on a downshift you moved the distributor?

Either bad gas, pluged fuel line, or like Galaxie says, the distributor moved, something in the distributor broke, coil went bad, or the timing cam pick-up went bad, ( un-adjusted)

I think it might be the dist gear? Timing is slipping?

Timing is advanced too far could be chain jumped tooth.Backfire through carb means fire reaching cylinder to early or intake valve closing to late.Also u say no plugs in it is smooth, Plugs in becomes rough this is also caused by timing advanced to far, That is that when cranking is rough.

It was a broken intake stud. Remeasuring and reordering pushrods tomorrow. A little too long I guess.

I had the same thing happen a short while back. And "ding, ding, ping" was pretty close to the sound it made. AFR had a bad batch of studs go out a while back. I called them after I located the problem and they sent me a complete set of new ARP's. The original studs were made by some other manufacturer. My engine suffered no damage but it could have been it could have been a mess if the failed stud and rocker arm had gotten it self lodged in the operating valve assembly before it was shut down.
You did not say which heads you were running but if they are AFR's you might want to give them a call.
Ras Daniel

Thank you for the tip! I bought ARP studs and the shop put them in and it runs ridiculously smooth now! AFR is sending me a kit too.

Thanks for the help!