i usually just get 87 octane... and then use SUPER 104+ octane booster, runs great... i tryed 91 plus the octane booster, i dunno what happened but i didn't like it as much...

 

i dont trust the 87..minium i would get is 91...

 

better the gas doesnt always mean better the performance, the higher the octane, the more resistant it is to combusting before the spark of the ignition, which is why in turbocharged cars its important to run higher octane. Basically dont run 87, car will prob retard the timing if it detects knock, 89 will prob be alright, i run 93 just cause it goes 87-89-93 where i live. u can advance the timing and run higher octane and get a lil bit of performance out of it, to a degree, but if u run very high octane (ex 100) then u basically not doin nething to benefit ur car...on a n/a 240 at least....

 

Yeah thats how it is down here....87-89-93. I could tell a little difference from when I bought the car and switched to 93 after about 3 weeks.

Crimsontide

 

we sell Union 76 100octane. There are a couple of 76 gas stations in the bay area that it. Also 76 has different types of 100 octane as well as 110 octane gas..

 

i would normally recommend buying 91... but for some reason my car just doesn't run as good when i run 87... but i guess thats just me... strange thing them corolla engines... oh and i guess i forgot to mention i ONLY buy chevron gas... so that'll make a difference as well...

 

i get 94 octane at sunoco in ontario

 

oh btw... SUPER 104+ doesn't contain lead does it?

 

u would have to check on ur own, u get that a the pump or u ganna buy barrels of it?

 

do what? I'm just concerned that I'm harming my engine if it does contain lead.... since someone previously mentioned that some station carried like 101 octane but it contained lead...

 

its usually when ya get to 110+ octane it contains lead, call up where u get ur fuel from and ask if its unleaded or leaded

 

91 S13, 100% stock KA24DE, 110K miles, 87 octane.

 

I'd strongly urge you to not purchase the cheap gas, the extra .10 cents is worth it per gallon, trust me. Read the other posts why.

Dr.

 

Thanks for the heads up, but no one in this thread has explained why (mechanically, chemically) exactly why higher octane is better. No one has provided first-hand evidence and knowledge, but rather "This is what I've been told" and other such second-hand knowledge. BTW, my car has never had knocking problems in my ownership, and I have never put in anything but 87 gas and octane booster (occasionally) in it.

Granted, 91 octane is probably better, but I'm not too sure if the difference in quality is warranted by the difference in price. And is there anything that says 87 can harm the 240SX engine?

My father, a PhD'd mechanical and aerospace engineer, approves of the 87 gas I use in my car. I think the only advice I would take above his is that of an independent Nissan specialist. Or another mechanical/chemical engineer. Any one out there fall under one of those categories? What is your take on this?

The FWD Altima, RWD XTerra, and RWD Frontier uses KA24DE engine, just as the 240SX does. But these cars are recommended regular gas by the government. However, the federal government (www.fueleconomy.gov) states that the 240SX should use premium. Why is that? How much do you trust Uncle Sam and his statistics?

And I know there's always some member who responds with "It's your car, your wallet, and you can put whatever gas you want because I'm an ******* and im indifferent". To those guys, don't bother. I'm sure many people are interested in the issues I have raised as well.

 

That's exactly why I started this thread. But....I think I'll still use premium.