Hi everyone...

Ok, I have '64 Dodge 330 with MP 440 Siamese block. 500 cubes, Indy SR heads, ports to max wedge specs, 11.42:1, '64 stage III intake & 3705 carbs, .solid .600" cam, TTI step headers, 3" TTI, MP race distrib ( no vac adv ), MSD 6 Plus box. 576 RW HP on chassis dyno.

The heads have Champion #298 (C63CX) race plugs in them... aren't these too hot a plug for this street/ VERY ocassional strip engine? The engine is fairly new, I have it @ 25 degrees initial adv - Going out to determine total advance shortly etc etc. I am slowly fine tuning it and still getting some detonation - could the plugs just be wrong for this set-up? Please post thoughts people - thanks !

NGK 5672A-7 is a great spark plug to use.

Check your numbers first. I'm guessing that you have C63CX plugs? Those are the racing plugs with the cut back electrode. Maybe post a picture of the plug so we're all on the same page.

The 63 heat range might be a little hot for what you're doing. Look at the Indy catalog to see what they recommend. I'm thinking that they'll tell you to go 61 plug for 11.4 compression ratio.

25 initial is a lot, how much advance to you have in the distributor? The Indy head usually runs best with something around 35 degrees of total advance so if you have more than 10 degrees in the distributor you could have a problem on your hands.

I run the A&A crossram version of the 64 model, indy little ez heads. I have had great luck with autolite ar3911.

34 total deg. timing

You could also run the colder champion plug, I run the C59x in my car, but its pretty much race only right now anyway, but its important you see what total timing is also, Id do that right away

An Autolite AR3911 is a Champion 61 heat range. An NGK 7 heat range appears to be a Champion 63 heat range.

If it was my engine I'd put the C61CX plugs in it and set it up with 35 total and go from there. If you need 25 initial to get it to idle then you will most likely need to modify the distributor. I'm not sure if the MP distributor can be limited to 10 degrees of advance. You'll need to look at it and see what version it is. The newer distributors are easier to modify, the old ones required welding or brazing to limit the advance. If that is the case then you might want to get a MSD distributor.

yes, C63CX plugs... typo sorry.

I drive mine on the street some, have a 620 lift roller cam, 8" converter, race it with too small air cleaners on it, and race it with mufflers. All the wrong stuff and for some reason it runs half way decent, I've run NGK, Champion, and Autolite plugs. The Autolites last the longest and run the cleanest. Motor ain't never been on a dyno so probably not tuned the best. I run either a Mopar Tach drive distributor with the advance plate welded almost closed, just enough to let it start easy when hot or a Firecore distributor setup the same, advance slot almost closed off and lightes spring in it.

... the engine had almost 80 initial!!! changed springs in the distributor and got it DOWN to about 25. Yeah, will check total, that's next anyway. I also want to see if maybe the timing cover might not be an older version. I'd like to know what TRUE tdc is on this - is there a really accurate piston stop tool that is good on wedge engines? I'm relying on the cover right now. Will also look further into this distributor also - thanks !

KEEP THE IDEAS FLOWING GUYS, I APPRECIATE ALL THE HELP !!!

Been using them same NGK plugs in my 63 which is an EZ headed 440/493 and with 37 total on 92 has no ping at all and I drive and race it on that same tune. Ron