Here is the deal I am going to get a 383 stroker kit and I want my compressions around 9.5 -10:1 but can it run on 92 octane gas. and if not what would be a good daily driver compression. THis will be my daily driver.

 

anyone?

 

i personally dont like to go higher then 9.5:1 for a street motor... athough there are thoes who are braver then i..


in my OPINION, the small increase in power from 9.5 to 10 just isnt worth the hassle/chance that you may get a pump gas prob, or that you might have to pull timing... and end up with less power...

 

10:1 is my personal choice of limtitation on a pump gas engine but I only use 94 octane anyway.

 

oh, id like to add that my old 400 was somthing like 10.2:1...

it ran fine on the street with premium.... most of the time..

every once in awhile, i would get some "bad" gas, and had to pull some timing....


if you are running FI it would do that automaticly, and while you lose power, the engine will be ok... if you're running carb, you would either have to add a additive or pull sometiming..

i personally think i was running the car on the ragged edge though, so if your setup has a bit more octane tolerance, it will be fine.

 

ok thanks guys

 

It depends on your cam as well along with your deck height and total quench. If you have good machine work on the block and run the proper gasket with something a little bigger then the L98 cam 10:1 should be no prob all day long. Having your combustion chambers on your heads polished is also cheap insurance againt detonation.

I have a 383 as well. The block is sqaure decked and I am running zero deck height over my pistons with a .041 gasket and fully polished chambers. The cam is 224/230@.050 and compression is ~10.3:1. No problems with 91 octane, it is the best we have in AZ. Once the motor is broken in and I am comfortable with the tune I plan to experiment with some 89 octane just for grins, maybe even tune a chip for 87 octane highway driving for road trips, but we shall see.

EDIT:

Alluminum heads

 

Boy that 383 is close to the 406 I built for my brothers 1987 Monte Carlo Aero Coupe. Head gasket is .038" and pistons are at (0) deck. Comp is 10.5 to 1 with steel 74cc heads. The cam is 221*/ 230 at .050" with 112* L/S and .467" lift with 1.52 rockers.

For MrDude_1: Most carbed cars have knock sensors so they will take care of any deto, but the 406 is as quite as a mouse on stock timing and 92 oct.

Auggie

 

a lot of variables here...aluminium heads 10.5:1 is no problem on my LT-1 with 91 -92 octain...

 

unless you convert to carb... then you stab a normal, noncomputer controlled HEI in there.

 

It will be a 383 stroker with a carb and it will also have World cast iron sportman 2 heads with a comp cam xe268 cam with 1.6 rockers and a zero deck with hyper.... what ever that word is pistons.But do you guys think that 9.5 to 1 is a good in between compression.

 

9.5 sounds about perfect for your setup. Do you have the slugs yet? If not -18cc KB hypers will give 9.5:1 with 64cc combustion chambers. I would not go over 10:1 while running iron heads. You may find that if the motor isnt setup to be detonation resistant you may run into problems.

 

hey thanks this has been really helpful