Quick Answer: Why Is High Compression Bad For Turbo?

Can you supercharge a high compression engine?

If you have a high compression ratio, such 9.5:1 or 10:1, you will only be able to run a small amount of boost.

To some degree, this can be controlled with boost retard devices, but we do not recommend that you set up your engine and supercharger to provide more than a 12:1 effective compression ratio..

Does higher compression increase torque?

Increase in compression ratio induces greater turning effect on the cylinder crank. That means that the engine is giving more push on the piston, and more torque is generated.

Is high compression good for boost?

Compression Ratio and Boost Pressure Relationship The compression ratio of your engine has a direct relationship to how much boost you can run. If you have a high compression ratio, such 9.5:1 or 10:1, you will only be able to run a small amount of boost.

What is a safe compression ratio?

The optimum intake-to-exhaust ratio could range from as little as 0.75:1 (for a low CR supercharged engine) to as much as 1:0.6 (for a very high-compression naturally-aspirated engine).

Is 150 psi compression good?

As a general rule a compression of 135 PSI or better is excellent, and a compression of 85 PSI or lower is extremely bad. The most desirable situation is that all cylinders give the same or close to the same reading, and that reading is above 135 PSI.

What can cause high compression?

High compression in a cylinder usually means there is liquid oil and/or high carbon deposit in the combustion chamber displacing room for air. The air gets more compressed (because the combustion chamber is essentially smaller) and the pressure reads high.

Do turbos increase compression ratio?

In dealing with forced-induction applications, it’s well known that increasing boost pressure on a properly sized turbocharger will increase power production (at least, to a point when the capacity of the turbo or fuel system is exceeded). … The higher the boost pressure, the lower the compression ratio of the engine.

Is high compression better for Turbo?

High compression is good for diesels, catastrophic for gasoline engines because of its volatility. So in order to eliminate that possibility, turbo engines are built with lower compression to avoid overheating the air fuel mixture before the spark plug fires.

What happens if engine compression is too high?

Basically the engine is quietly destroying itself! Holed pistons will happen very quickly! … If the compression is too high for the fuel used pre ignition will occur, the mixture will ignite from the heat of being compressed before the piston reaches (at least close to) top dead center.

What is considered high boost?

“high boost” is more in the limitations of the motor and the turbocharger than it is in “the tune”. and it varies depending on how built your engine it, what its compressions is… also on the size of your turbocharger… 21psi on a stock twin is considered really high boost….

Do high compression engines wear out faster?

Higher compression engines tend to blow head gaskets a little quicker. As long as the engine is built to handle the high compression there is no issue. Diesels last so long because they are overbuilt like crazy.

What is the highest compression ratio for 93 octane?

9.5:1We are being told by most piston manufacturers that 9.5:1 is the most you should run in an engine with cast iron heads on 93 octane pump gas. Because aluminum conducts (dissipates to the cooling system) heat much faster than cast iron does, you can run 10.5:1 with aluminum heads on 93 octane.

What octane is needed for 11 1 compression?

95 Octane. Gasoline with this octane number is known in Indonesia under the brands Pertamax Plus (produced by Pertamina), Super Extra (produced by Shell), and Primax (produced by Petronas). This type of gasoline is advisable for car engines with compression ratios of 11:1 to 12:1.

What is the highest compression ratio for 91 octane?

9.3 : 1To release all the potential power of 91 octane gasoline, it is necessary for an engine to have a compression ratio higher than 9.3 : 1. _______3. Any gasoline engine will efficiently burn any octane fuel.

Does higher compression mean more power?

A higher compression ratio — say, from 12:1 to 14:1 — means higher combustion efficiency. Higher compression ratios and combustion efficiency mean more power with less fuel, and fewer exhaust gases.