93 Octane
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Instructor
Joined: Jan 2013
Posts: 114
Likes: 5
From: Highland MD
93 Octane
I'm going to be installing PRC CNC ported 243heads with 61cc combustion chambers & gaskets to put me at around 11.1:1 Static compression ratio , can anyone tell me if they've run this amount of compression on 93octane unleaded with good/bad results ? Cam is Texas Speed 224R......224/224 duration , .600 lift intake & exhaust 112 lobe separation , thanks in advance to you good People of the Forum !
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From: Hickory NC
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I'm running reasonably similar heads, cam is a little larger, long tubes, A4 with 3.42 and do fine on 93 octane. When I'm home I'm able to get ethanol free fuel.
I've had to run 91 octane on some trips when it was the only fuel available and still did fine.
I've never run anything lower than 91 but know others who have in emergency situations when that was all they could find and the car ran ok. Not as much horsepower as with better fuel due to the PCM retarded timing but it'll still get you home.
I've had to run 91 octane on some trips when it was the only fuel available and still did fine.
I've never run anything lower than 91 but know others who have in emergency situations when that was all they could find and the car ran ok. Not as much horsepower as with better fuel due to the PCM retarded timing but it'll still get you home.
Thread Starter
Instructor
Joined: Jan 2013
Posts: 114
Likes: 5
From: Highland MD
93 Octane
I'm running reasonably similar heads, cam is a little larger, long tubes, A4 with 3.42 and do fine on 93 octane. When I'm home I'm able to get ethanol free fuel.
I've had to run 91 octane on some trips when it was the only fuel available and still did fine.
I've never run anything lower than 91 but know others who have in emergency situations when that was all they could find and the car ran ok. Not as much horsepower as with better fuel due to the PCM retarded timing but it'll still get you home.
I've had to run 91 octane on some trips when it was the only fuel available and still did fine.
I've never run anything lower than 91 but know others who have in emergency situations when that was all they could find and the car ran ok. Not as much horsepower as with better fuel due to the PCM retarded timing but it'll still get you home.
