I am goin to the track this weekend and i was wonndering if it would hurt to mix 100 octane gas and 93 octane in my car with stock injectors. i was gunna put like 3 gallons of 100 and 4 gallons of 93. I was also wondering how much PSI will a stock N/A 3000gt SL motor hold safely?

why are you running higher octane? you have a N/A automatic, changing octane isn't going to do anything for you. Why do you want to know about PSI?

Twizted 3kgt is right, if you have a N/A stock 3000GT then you don't have turbo's, or are you wondering how much you could run through it if you did turbo it?

And yes if you are N/A then the 100 octane fuel is not needed, you would be wasting money on it.

im wanna run higher octane to clean out the engine, and i was wondering how much PSI the motor will hold if i wanted to turbo it.

8psi probably, I dont think that 100 octane would clean it. Do N/A's have a knock sensor and timing control? if they do, then more octane would equal more power for him...

Yep, that is probably about right, because N/A's have a higher 10:1 compression ratio you are going to be pretty limited to what you can push through it.

mel I believe the NA motors have a knock sensor not sure about a timing control

They have timing control, but it won't advance the timing past the stock timing maps. It only retards the timing if there is knock to a lower timing map. Anything above 93 octane and you will just be losing power.

When everything else is the same, More octane = Less power