Hey so my engine has been pinging if you followed my last thread and we tried timing and fuel and all that didnt work so were gonna try the plugs now. my current plugs are NGK UR4's. the other guys said to try a colder heat range plug. what do you think i should use? Its a 350 with a few upgraded parts but nothing major. just a light torque rebuild like flat top pistons, moley rings, a better camshaft etc but nothing top of the line but better than stock.

 

Did you try this, change the gap on the plug? We were just talking about spark plug gap yesterday and my coworker said his nephew just did a tune up on his car and it pinged, he told him to change the gap and it stopped.

Do you know what gap you are using?

 

They were gapped at like .038. I bought some ACDelco R45TS's and gapping at .045.

 

I'm fairly new on this site so I don't know what you have tried or what your system is like, so question, are you running a MSD box or anything?

Also before you install the new plugs, try closing the gap up to like .025-.030 and see what happens.

 

Nope im not running anything special. And i put the new plugs in and they run great! such a big difference. Like 90% of the pinging stopped. The rest is just ignition timing

 

Changed my TR55's out with NGK TR55GP platinums, although the TR55's were due for a change anyways I noticed a pretty big difference. I can feel a bit more power and it idles a little smooth at 900 rpm where with the Tr55's it was around 1,100 ar idle. I changed all of them from the top and only removed the 2 bolts to move the egr pipe over. It was a ***** for the last #8 one, but managed to do it all under 2 hours. lol

 

Doesn't tell me much, since "nothing special" could be a stock points distributor, or a stock HEI. The difference will be huge on one vs. the other as far as plug gap and timing are concerend.
If it's HEI you need at least .045, but sometimes a little either way can help. My MSD says .045-.055, but tighter works better for mine. I run .044".