Here you go.....XR4's. Through those back in and just back from a 10-12 mile ride. About half of those on the highway. Averaged about 70mph. A couple pedal mashes to 100+ with a steady cruise afterwards
At 15*. Original dizzy, untouched. I run VA also. Runs and drives great but these plugs looking this way to me, says it can be better
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I think you'll be pleasantly surprised with the response if you get the timing mark into the bend (or at least very close) of the ground strap. Of course everything else will need some re-tweaking afterwards, but hey..that's tunin'!
Here are the NGK's I just ran today. Is this more what I should see at the strap? Previous plugs were #1 plugs. This is the #2 plug(indoor/outdoor lighting). Starting to wonder if these Accel yellow 8mm wires are garbage....I can't see a stock 1406 jetting etc being too much for a big block. Even a stock one. I could be wrong.
Stock jetting sure can be too rich for a given combe; the engine will want it wants for the conditions, fuel quality, etc. As far as the timing read on the NGKs, there isn't much of a defined mark as there was with those first plugs, at least to my eyes and screen anyway? "If it was me" I'd put in a couple of new plugs and bump the initial to 18 and drive it (without stomping it hard) and see how it feels. Give it some miles and then take a look at the new plugs, if you like the burn mark and the throttle response, then go from there. Of course....this is kind of "going down the wormhole" of tuning but you should IMO always get the timing squared away before getting into the carb.
