I can't get the right AC plug today and found some "correct" plugs for my Vortec BB at Walmart.(Here in the backwoods you have to "make do")

They are projected nose platinum but I went to Autolite's website and could not get a heat range. Will these be OK on a NA 9:1 ? Is it in the same range as the Delco 43's ? Thanks

Anyone? Anyone?

Try www.sparkplugs.com for some info.

Thanks, I went there and got some info,,still wondering if they are too hot for a NA vortec BB with 9:1 and making about 450HP. Seems they are in the range of NGK 5's ? HELP!!

N/A vortech BBC must be a custom build.I had 461 BBC with vortech heads and I ran cooler 42 ac plugs with projected nose.These fast burn heads when run without a computer engine manigement system can't handle a lot of timing(I found 28*about max).I ran the cooler plugs for safety reasons.I over loaded a motor with these heads and tupliped a set of intake valves in a heart beat.Be carful with these heads in regards to heat and ditonation.

When you say you overloaded what do you mean? To much timing? It's a mild custom,raised the comp to 9:1 and put the zz502 cam in and oval Dart intakes with 800 holleys from a HP500. I'm making about 450HP and put v6 modules in for around 28 deg adv tot. Just wondering if these plugs are about the same as a 43 AC would it cause a problem?
After a WOT run (later when tuned and broken in) if the plugs are a little sooty does that mean I'm not pre-detonating or does it only mean I'm a little rich?

What pistons are you using.With those heads and flat tops you will be at about 9:1 with flat tops.They have small chambers.When I detonated it I had put a bigger prop on and when comming up to speed it started to slow down as soon as I got it up to about 4000 rpm.All the plugs burnt the ground straps off.I couldn't here the detonation.By overloading I meen that it was to much prop(limiting the rpm).I tend to let my motors run a little on the high side.That cam should be pretty good with that compresion ratio.I would degree it because they are around 104 ilcl.I would retard it a bit.Watch the reversion with that cam.I reground mine to a 112 lsa and even with long risers it sucks water in if I let it idle too low.