What vortec spark plugs?

[neverendingproject]

What spark plugs do I use for my vortec heads (96-99 SBC)? I know they are picky and they have to be longer than normal SBC plugs, but what gap, brand, and heat range should I look for? After two weeks of cussing, I figured out my ignition problems were the plugs, so im off for new ones.

I used autolite (all the parts store sells) and I dont want platinum plugs because I've heard the have a general heat range and not the best thing for the vortec heads.

Thanks guys.

 

[1979jimmy350]

your gap is going to depend on your ignition system, not the head it depends on how much voltage your coil is producing.

 

[jms]

Champion # is RS12YC, gap @ 0.045. Stock or Summit coil.

 

[neverendingproject]

I have a MSD distributor and coil, but no box, do I need to swap back to a stock coil?

 

[1979jimmy350]

no a aftermarket coil will produce a larger voltage allowing a little bit larger gap to be run, your best bet is to find a plug that works then play around with the gap and see what makes it run the best

 

[jms]

I have a MSD distributor and coil, but no box, do I need to swap back to a stock coil?

I was just pointing out that I've used this plug/gap combo with both the stock '85 HEI setup as well as with an aftermarket (Summit) HEI; engine is a carbureted 350 w/ Vortec heads. I've also used hotter RS14YC plugs to address lousy #7 and #8 plugs; all plugs look to be a little on the white side.

 

[dyeager535]

Just go buythe AC Delco plugs for a Vortec motor and run them.

"Normal" HEI applications will jump anything .035-.060" gap, and GM did just that with the exact same ignition setups, depending on year and engine make.

Anyways, the Delco plugs are great plugs (apparently NGK's) and not that expensive if you can find someplace that sells them.