if there is a thread for this could someone link me to it

does using medium rather than regular gas actually do a performance difference? mainly for a stock d16y8?

 

*Premium

 

For a stock y8, nothing at all. The higher grade octane is more resistant to predetonation, or knocking, but on lower compression engines 87 octane is recommended. Engines like the B18C1 and Toyota's 2zz-gte are high compression engines, which are more prone to predetonation, and require 93 octane.

 

I had stumbled across a nice table that showed compression ratio's and the octane typically needed for them but I can't find it now.

Everything I come across now is without engine management systems so is about 10 octane higher than is required in our vehicles on average.

 

My d15z1 got worse gas mileage using premium. Just stick to regular.

 

I believe it depends on each individual car, regardless of what the dealer manual says. I only run 91 in my ZC and when I tried 87 again, my car sputtered a bit when it started, ran much rougher, and idled rougher. Switched back to 91, runs smoother again. My dad has a 1984 accord, original engine, 315k miles, has only seen 91 since 1984 when he got it. See what your car runs better on

 

I think all the gas can work at the gas station dunno lol

 

I think this might be due to the ECU learning over time. Also if you don't periodically Italian Tune-Up your car or seafoam it, carbon can build up in the combustion chambers forcing you to higher octane to stop pinging.

I bet if you tried the 87 octane and reseet your ECU at the same time it wouldn't be so rough.

 

if the manual says to run 87 and the motor is stock run 87 octane. 93 octane takes longer to burn off... so u end up with a bunch of unburnt fuel because your compression and flame isn't hot enough to burn it all off... your just wasting ur money putting premium in a stock motor that's tuned from the factory for 87....

 

The manufacturer specifies a fuel grade based on the way the engine was built and the intention of the engine. Having that said, if you have a stock vehicle, use the fuel specified by the manufacturer. Increases in octane rating have little to do with power, more so the resistance to ignition. Naturally, a turbocharged or supercharged engine will often specify higher octane fuel to prevent engine damage. High rpm engines and lots of timing advance will often result in the need for a less volatile fuel (higher octane) to run as desired.

Some fuel refiners will advertise additional cleaners, like shell does, in an attempt to sell more premium fuel. Every fuel station I have come across runs a detergent based blend irregardless of the octane rating.

 

Y8 / OBD2 engine control includes a knock sensor that signals the ECU to pull timming back if detonation is detected. Until you make some serious changes to the engine, 81 / 87 octane is fine, more important / better value to keep good oil and filters in the motor than spending extra $ every tank for no benefit.

 

bASICALLY EVERYB

 

Wat

 

Basically everybody said what i said in different ways.

 

yes they did! that Y8 will run best on lower octane.

 

Damn , never expected to get this much replies . This forum is so nice and helpful . Thanks guys ! Guess I'll stick with regular

 

Good call, slugger. Make sure to run the can of seafoam through it every now and then

 

I'm sorry but i just don't get what you are trying to say haha. what is a can of sea foam? and why am i a slugger?

 

Sea Foam is petroleum. it can literally go in every orifice of your engine an cleans. I'm an advocate, I love it. Google some videos or info on it. you can also read through all the "it blew my motor" bull here on HT.

 

It's not bull. Seafoam, when used correctly, will completely clean your motor. That means that if you have a glob of crap holding a failed seal together, it'll can clean that glob off, and your already-blown seal will show itself. Motors that are "blown" after seafoam (or any engine cleaner) were already damaged and in need of repairs.

Motors have a recommended fuel rating from the factory. If the FSM calls for 87, you don't get a "special motor" that just runs better on 91 sometimes. If the motor calls for 87, but runs like **** on 87, you need to do a tune-up.