Hot Rods spark plug heat range ??

I have a SBC 283 bored to 302 , 305 heads , slight Engle cam , hei dist. Edlebrock 600 cfm , need advice on what plugs and heat range ...

 

***uming 305 Non Vortec heads ,?
Flat top or dome?
Flat top ac 45 ts 9-10 :1
Gap 40-45
10:5 -11ish I would say ac 44
I more likely also start with 15-18 deg
Of Initial total on mechanical advance
Set around 34-38 total to start off with.
Notes to fine tune ,
Use Ngk Chart & cross for
Heat ranges

 

AC 44 or 45 plugs (I'm on vacation and can't remember exactly right now) in my FED. Mild cam in an otherwise stock 305 running a TorkerII Edelbrock with a 600 Holley and HEI with vacuum advance eliminated, lightweight mechanical advance springs with 36° total timing. It's been working fine racing it for 3 years now.

Lynn

 

305 heads take a "peanut" plug, so R45TS would be a good place to start.

 

peanut?

Ben

 

5/8" hex tapered seat, vs the older 13/16" hex gasket type

The letter T in the AC part number tells us it's tapered seat. Chevy started using them in most engines starting in 1970 model year.