383lt1impala

iTrader: (33)

what fuel should i run i dont really want to run leaded cuz i dont want to replace the o2 sensors often.

5.3LJimmy

iTrader: (10)

Can you tell me about the rest of your setup? What cc are the heads, what head gaskets, and what cc valve reliefs in the pistons? Using 62cc for the heads and a stock gasket thickness I get 11.96SCR and 8.77DCR. That can run on premium pump gas with a good tune. If I play with the numbers to get a 12.56SCR the DCR is a little over 9.2. Which is high for pump gas, but will be fine with 100 octane unleaded(if you can find it in your area).

Haans249

iTrader: (24)

E85 is good

slammer454

you should be fine on E85.

383lt1impala

iTrader: (33)

heads are 70cc gaskets are .53 ccs i dont know my builder check everything and he said is 12.56 to 1. most of the info is in my sig. is e85 safe even wit a 300shot?

JonCR96Z

iTrader: (33)

It's hard to know what you need if you don't know anything about the engine. Using the numbers you gave on a 383 I'm having a hard time seeing 11:1 SCR.

LS1MCSS

iTrader: (18)

With a 383, .053 gasket and MS4 cam, I get 10.91. I think your builder is making a mistake in his math.

http://www.rbracing-rsr.com/compstaticcalc.html

elias_799

iTrader: (8)

^^^ he might have different pistons, witch raise the cr even higher.

2001 Pewter WS6

iTrader: (43)

I ran 12.5:1 on my 408 before I got different heads... Sunoco 93

383lt1impala

iTrader: (33)

Can't used e85 the nearest station is about 40 miles away. Ill just stick with some hi-octane unleaded fuel.

slow trap

iTrader: (22)

it must have dome pistons with those big cc heads and thick gaskets. if that scr/dcr is correct then i would run a 50/50 mix of 93 and 100 or more octane unleaded or the very least have a conservative tune in it for the street. if no one close sells 100 + you can probably order a drum of it from somewhere.

The Alchemist

iTrader: (19)

Well, the question I have is, is this a street car or track only? If it's track only, a lot of tracks have 100 octane on hand.

383lt1impala

iTrader: (33)

track car only very limited street use.

Nitroused383

iTrader: (10)

Tune it in speed densisty and get rid of the o2 sensors. You do not need them, run what ever fuel you want. Or just run it in OLMAF if you want to use the maf but if not just run OLSD. Either way no need to use o2 sensors unless you need them for emissions.

383lt1impala

iTrader: (33)

hmmmm i never thought of that good info!