Nitrous vs. compression?

[94' cobra 351]

The guy I bought my mustang from told me the compression ratio is 10.5:1. I know that supercharging it is not an option with that high of compression and hyper pistons. So I was going to go with 125 zex wet kit instead.

Somebody had told me that nitrous loves higher compression engines, and it would be safe to run a 150 shot. Is this true? What is the logic behind that? Essentially you are increasing pressure inside the cylinder just like a supercharger so I don't understand why it is safe for me to run nitrous with that high of compression?

Also, I use 93 octane fuel. Would I need to upgrade running 125 shot? I think I heave heard of kits that basically add an octane booster while you are spraying? I might be wrong on that one.

Some clarification on running nitrous with my high compression is greatly appreciated!

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[rocket5979]

The guy I bought my mustang from told me the compression ratio is 10.5:1. I know that supercharging it is not an option with that high of compression and hyper pistons. So I was going to go with 125 zex wet kit instead.

Somebody had told me that nitrous loves higher compression engines, and it would be safe to run a 150 shot. Is this true? What is the logic behind that? Essentially you are increasing pressure inside the cylinder just like a supercharger so I don't understand why it is safe for me to run nitrous with that high of compression?

Also, I use 93 octane fuel. Would I need to upgrade running 125 shot? I think I heave heard of kits that basically add an octane booster while you are spraying? I might be wrong on that one.

Some clarification on running nitrous with my high compression is greatly appreciated!

I am running a 100 wetshot on my engine which is 10.75:1 CR. The reason these high CR engines do not like boost is because boost heats the intake aircharge and tends to make it easier to detonate. The lower the CR the easier it is to control detonation. When running higher CR it is harder to curb it and still run a somewhat normal fuel like 93 octane pump gas.

Nitrous will not heat the IAT's like a supercharger will. In fact it will cool it one hell of allot which means the combo is safer because of it. The things to take into accouunt when sizing a shot of nitrous for a vehicle is: can my engine and drivetrain hold the power, and can my fuel system support it? There can be more questions than that but those are some of the more basic ones.

Running a 150 shot, especially if rated at the rear wheels, will likely tax your stocker fuel system beyond its current fuel flowing capacity. Either get a bigger fuel pump or run a standalone fuel system for the nitrous itself would be my suggestion. As long as the engine is built well, the nitrous system setup right, tuned right, and operated correctly you should not have any real big problems running a 150 shot on your engine. It is getting kind of close to the edge IMO but it will probably hold it for a while. It may be safer to start with a 125 shot like you mentioned just to check it out to see how you like that instead of thinking of going 150.

 

[94' cobra 351]

Thanks man, exactly the info I was looking for!