Engine: Another dreaded spark plug question

[Guest]

I tried searching out this question on the web, but didn't get satisfactory answers so here I am in more familiar territory again...

I pulled out an Autolite AP26 plug from my recently bought Avanti project with the chebby 305 engine and want to replace them. Did a cross reference search and got maybe two dozen possibilities, which only further confused me!

Should I just get a box of the same AP26 plug, or is there another one you would suggest? I'd appreciate it. Thanks!

[Bud]

The Autolite AP26 is a platinum plug which will be a good plug for your engine. You can use the regular 26 if you don't want to spend the extra money for the platinum plug. The AC R45TS or Champion RV17YC will work too. Bud

[Guest]

Great! Thanks, Bud!

[Guest]

I got a box of these AP26's per Bud's recommendation. This being a chev 305 they're going into...what gap should I use? Thanks!

[StudeRich]

Tom, does it have the Electronic Ignition conversion or GM HEI? They usually get a wider gap than point ignition.

[Bud]

If you have an original GM hei distributor, the plug gap can be widened to .045, but I doubt if you will notice a difference in engine performance with the gap set anywhere between .035 and about .060. The wide plug gap was used with the smog controlled engines which ran a leaner idle fuel mixture. If you have a stock point type distributor or aftermarket electronic ignition, I would recommend a .035 plug gap. Bud

[Guest]

Thanks so much, Bud & Rich!