Best Fuel Option

[MOPARJ]

Let me start by redescribing my combination: 73 based 318, stock bottom end, rebuilt heads, hardened seats, stock compression replacement pistons, stock head gasket thickness, Comp XE268 cam, .477/.480 lift @ .050, matching springs, Hooker headers, Edelbrock performer intake, 600 CFM eddie manual choke carb, dual snorkel. mid seventies style air cleaner with stock replacement element.

904 trans with TF2, stock verter, 2.76 7.25 rear.

What is the grade of fuel that I should be running? Is 87 ok, due to the still lower compression, or should I run 89? I have 10* of initial timing at idle and there is no pinging. This is with 89.

Also, Im guessing 260-270 horse at the crank, does this seem like a fair estimate?

 

[ted_sweet]

use the lowest octance that has no ping.

 

[Johnny Dart]

Dam,you have a hot little 318.
Ditch the dual snorkel for a open element with a K&N
Put in 92 octane and bump up the timing to 35 total.
And light em up !!!!!!!
Now we arte talking !!!!!!!!!

Unless you are daily driving and looking for MPG's.
Then run 87 with your 10 advance.If it isnt pinging you are fine.

 

[moper]

Whatever's cheapest that wont ping is fine. You may find the extra detergents in the high grade will keep it happier longer, but if it doesnt ping, cheapo fuel wont hurt it.