what plugs to use in 462 heads?? heat range??

[oldsman71]

I know it takes the big gasket seated plug but what heat range? all the shorty plugs are around the a/c 43 range I ushally use a hotter 45. it will be around 10:1 compression on 92. thanks cobey

[Bamfster]

I ran Autolote 86's when I ran 461's w/around 10:1.

[oldsman71]

have autolites worked good for you? I ran ngk's a long time ago. header plugs would help a little?
thanks Dan I guess I need to order some

[yellomalibu]

I don't know if shorty header plugs work as well, better, or worse than the standard length plug - I've never used them - but I would assume that the factory length are that length for a reason. If you have the clearance to use a standard length plug, that's what I would use.

...and I always heard "you don't put autolite plugs in a chevy - they're for fords... you put Delco plugs in a chevy! " but I can't complain about the autolites I had in my 350 for several years. They worked fine.

I've had good luck with the 45 heat range Delco plugs in the Chevelle... never tried hotter or colder plugs.

Honestly, I don't really understand what the difference is between a "hot" and "cold" plug.

Can someone explain what the difference is between a "hotter" and "colder" plug? ... and why an aluminum head would want one over the other.

The only thing I know is that the 305 in my current truck had plug fouling issues before I bought it. I installed one heat range hotter, and it's been about a year now without fouling out the plugs.

[Bamfster]

Hotter plugs hold heat in the plug/chamber longer, colder transfers it out quicker. I tried hotter and colder and never saw a difference in ET or MPH. Never had a problem with Autolites .... plus they're cheap (kinda like furds). Now I run Champions with my Darts ..... that's what Maskin recommends, so that's what I run.

[SuperBuickGuy]

the tip is longer on a hotter plug. In a boosted motor, having too long of tip makes a nice glowing tip to pre-detonate the mix. Conversely, the longer the tip (within reason) the better the burn because more of the kernel is exposed.

I used 43s and 44s on my b&m blown SBC, I used 45s with my 462s and non-blown applications. I used 44s with aluminum D port heads.
45s should be fine for what you're doing. If you have a lot of knocking (predetonation), get a plug with a shorter tip (aka "colder plugs")

[oldsman71]

thanks all

[Scott Liggett]

I ran AC R45TC's forever on my Impala with '186' heads. My particular engine didn't like the colder plugs.

The AC's are just as short as the lousy Accel's and last longer.

[oldsman71]

I ran AC R45TC's forever on my Impala with '186' heads. My particular engine didn't like the colder plugs.

The AC's are just as short as the lousy Accel's and last longer.

ya the guy that has the malibu race car was runnig the
accels and they didnt seem to want to stay lit, a couple just stopped working new ones were fine. no foul or anything

[Scott Liggett]

ya the guy that has the malibu race car was runnig the
accels and they didnt seem to want to stay lit, a couple just stopped working new ones were fine. no foul or anything

My experience is they suck. I wouldn't buy them if they were $.49 each.