highest comp. for FI and 105 octane
highest comp. for FI and 105 octane Whats the highest comp. ratio to run with 105 octane fuel on an FI engine.
Lets say the engine is a 348 cid ls1 and will have a max boost of 30psi
In theory an engine at 9.5:1 would have more power then an engine at 8:1 at x amount of boost. I know this is pretty general but just thinking out loud.
Lets say the engine is a 348 cid ls1 and will have a max boost of 30psi
In theory an engine at 9.5:1 would have more power then an engine at 8:1 at x amount of boost. I know this is pretty general but just thinking out loud.
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In theory an engine at 9.5:1 would have more power then an engine at 8:1 at x amount of boost.
In theory the engine at 8:1 would make more power at 30psi because you could actually run 30psi at 8:1.
Assuming its 105 octane E85 alcohol fuel blend 8:1 will be pretty good...
Wanna boost alot drop the compression...
All the old school first generation mitsubishi's making big power on the stock turbo and bottom end all had 7.8:1 compression from the factory.
Mainly Cylinder pressure determines the ignition/pre ignition point.. Take a 9.5:1 and a 8:1 engine run them at the max boost level each can still run a good timing curve on.. The 8.1 will handle alot more boost with the same fuel and approzimate timing curve.
The cylinder pressures will be close to the same but the 8:1 is sqeezing a larger volume of air down to the same pressure.. More air = more fuel = more power...
On forced induction its the effects of dynamic compression and how many lb/min of air you can flow.
Matter's if it is a Turbo or Supercharger. Turbo -you want a lower compression like 8-1 or 8.5-1 for that much boost. With a supercharger we have run 11-1 compression at 24lbs of boost but this is with c-16.
Originally Posted by Slowhawk
Matter's if it is a Turbo or Supercharger. Turbo -you want a lower compression like 8-1 or 8.5-1 for that much boost. With a supercharger we have run 11-1 compression at 24lbs of boost but this is with c-16.
What if its a 3.3 twinscrew charger?
On that 11-1 engine did it have a cam with some decent duration on it?
thanks for the replys
