Chevy Nova Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter #1
Who's still running the high comp pistons on pump gas? Bought a `67 with
`66 numbered L-79 BUT the previous owner opted for flat tops. Everything is
correct as in Camel Hump heads, Winters intake, Holley, NOS camshaft, etc.
Strange that he even opted for 1.6 ratio roller rockers but gave up compression.
It's not a daily driver. I bought it for the nostalga of the good ole days and
the horsepower to boil the tires if I want to. Is 93 octane possible to kill the
detonation? If worse comes to worse, there's an airport a mile from the house.
I could buy 100 octane Low lead. Interested in what ya'll are doing for gas in
the old/original hot rods.
 

·
Registered
Joined
·
94 Posts
i have 10.9:1 compression and i run a 50/50 mix of 112 sunoco blue and 93 sunoco
 

·
Banned
Joined
·
26,231 Posts
try adjusting the timing... i'm at 10.75-1 and i run straight premium with no issues...

but i am running aluminum heads (a little more forgiving)
 

·
Registered
Joined
·
332 Posts
I have 10.9 measure CR, but with aluminum heads and a healthy cam (36 degrees max). 93 octane at nearly sea level too.
 

·
Registered
Joined
·
767 Posts
i have 10.9:1 compression and i run a 50/50 mix of 112 sunoco blue and 93 sunoco
I run bout the same deal 50/50. 110 VP/94 pump
It runs on just pump gas with no detonation , but it runs better with race gas mixed in.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #9
Mission accomplished

Thanks guys. I can see where this is headed. Straight to the machine shop for a set of pistons. Those answers were what I was looking for.
 

·
Registered
Joined
·
3,895 Posts
A loose converter is a life saver for a high compression engine trying to run on pump gas!!:yes:

Get ready for the "seasonal" fuel changes.:devil:
 

·
Registered
Joined
·
1,286 Posts
Who's still running the high comp pistons on pump gas? Bought a `67 with
`66 numbered L-79 BUT the previous owner opted for flat tops. Everything is
correct as in Camel Hump heads, Winters intake, Holley, NOS camshaft, etc.
Strange that he even opted for 1.6 ratio roller rockers but gave up compression.
It's not a daily driver. I bought it for the nostalga of the good ole days and
the horsepower to boil the tires if I want to. Is 93 octane possible to kill the
detonation? If worse comes to worse, there's an airport a mile from the house.
I could buy 100 octane Low lead. Interested in what ya'll are doing for gas in
the old/original hot rods.
Check to see if the crank was rebalanced when the pistons were changed, you might need to have the assembly rebalanced if you're going to change them again. There will be some vibration at around 2500rpm if it ain't right.
 
1 - 11 of 11 Posts
Top