I live in Bay Area and my friend just told me that there is a gas station that sells high octane gas (100) near where I live. Is it safe to use this gas in G35. I know that the higher octane rating increases the performance of the car but I still wanted to check with you guys and see if anyone has used this high octane gas and what were the results?

 

running higher octane gas will help with performance to an extent. 100 octane gas is probably overkill. i am guessing it is probably about 5 bucks a gallon. i used to run 110 in my yamaha R1 with 12:1 compression, and noticed no difference. in fact it actually dynoed with no change.

it is completely safe to run in the G as long as it is not leaded, but i would guess that no gas station would sell leaded gas. go ahead and satisfy your curiosity...but i would predict no noticeable change.

have fun!!

 

Yes you are right. It is about $5 /gallon and I just wanted to buy 5-10gallons and I just want to satisfy my curiosity. Since it is in California, I am sure it is an unleaded gas.

 

One thing to consider and this was said to me by one of the Techs at a local infiniti dealer whom is a gear head and tunes Nissans. He said on the G35 coupe they have only found that the Higher Octane stops the pinging that sometimes occurs and doesn't really help much HP wise.

This was in response to a question I asked about stopping mine from pinging at low RPM/High torque situations. He told me that pump gas in japan (as confirm by yuichi) has a higher octane rating I believe 100+. This just makes the car run better according to him but not necesarily faster. Another thing he pointed out is that when a higher octane gas is used the ECU will tune the car's AIR/FUEL ratio as well as some other aspects for the higher octane.

When you switch back to a lower octane the car may actually seem to run worse because of this. He actually recommended to me to reset the ECU both times if I decided to switch to a higher octane then back. Just some extra info if you decide to go for it. Let us know how it works out. Peace. [img]/w3timages/icons/cool.gif[/img]

-Jason
Laser Red '03 6MT

 

Hi,

My friend also told me about this gasoline. It is crazy to buy that much gas, but if you mix 100 octane with 91 octane, you can get about 94 octane, which is what I would put in my car if I was on the east coast....

There is a gas station in San Jose and one in Redwood City that sells 100 octane.... Secondly, the only warning that I got about this is that 100 octane burns hotter than 91 octane, which means that the exhaust going through your pipes is hotter... Therefore, you want to make sure that if you do use this gasoline, that the higher temperature does not burn out your O2 sensor.... This is the only warning that I got.

My friend has a WRX and he has used it and had no problem. He says that your HP increase is minimal if at all, but the reaction of the car is much better, meaning that if you step on the gas, the car goes without any delay... Again, this is on a WRX, not a G35, so I don't know what the deal is with our car.... If you try it, let me know.

Here's to alcohol : The cause of ... and solution to all of life's problems.

- Homer Simpson

 

from what i understand there is no benifits to higher octane beside the reduction of ping and such. from what i understand the ECU is tuned for 91 octane and slightly less there for when u run a higher octane the computer cant benifit from it so it will only run smoother. You can have the ECU programed to run on a higher octane and then u might see gains. this is what i got from reading some stuff from the techno square site.



<a href="mailto:Carlos3186@hotmail....otmail.com</a>

 

It is possible to still get leaded race gas so you should be sure to not get the wrong fuel as warned about by others. The gas will average together. 6 Gallons of 100 octane and then topping the tank off with 91 octane to make the 20 total gallons should net 93.7'ish (actual octane can vary from pumps). It may make a little difference but I don't think it'll be much, especially for the cost.

 

hey, i live right next to redwood city. Where is the gas station that sells 100 octane located? I'm interested to give it a try, I'll let you guys know the results afterwards.

 

Here are my 2 cents. I just took a semester of thermodynamics, and we conducted an engine lab with varying levels of gasoline octane. We used 87, 93, and 100 octane. The higher octane actually produces less HP, with the 87 producing the best hp numbers on the dyno. The benefit of higher octane gas is that it has a higher Lower heating value, so it will prevent engine knock (early ignition) in cars with a higher compression ratio. So if you modify your engine internals or go the FI route, high octane gas is good for you. If not, then you are wasting money. Just buy the recommended gas.

 

Ok, I'm gonna go out on a limb here and perpetrate like I'm one of the motorheads for a minute:

My understanding of the higher octane gas is that it burns slower than lower octanes. If you advanced your timing you could take better advantage of the higher octane gas because there wouldn't be early detonation like there would be with the lower octanes. There's an optimum point for your car to fire; too early and your car pings, too late and you lose performance.

In your case, since your computer will stay pretty close to stock settings and can't advance enough, you may actually achieve WORSE performance because your car won't be firing at the optimum firing point for the octane. In theory, it would be the same as retarding your cars timing.

Slight gains can be found in slightly higher octanes (94-96 octane(?)) but up above 100 you're wasting your money.

Like someone mentioned, when you go back to lower octanes your ECU has advanced the timing so it takes it a while to recalibrate to the lower octanes and you're likely to have pinging unless you reset.

And now back to the REAL motorheads...

 

My car tends to ping a little in 4-5-6th when it's really hot outside and I do a pull from 1st to 5-6th gear...the 94 octone we have here is good to prevent that but it still didn't give me better 1/4 mile numbers than a fresh batch of 91.

 

Paul, in your schools experiment, I'm assuming that the engine you used in your tests was tuned for 87 octane?

If you'd been using an engine tuned for 93 octane I'm pretty sure your peak hp wouldn't have been at 87octane. As you stated, use the gas your engine is tuned to use...

 

Some of the Union76 stations offer 100 octane gas. See http://www.union76.com/products/76racing.asp#COM100

RainMeister
'04 G35C 6MT, diamond graphite, premium, nav, aero

 

Auto mfrs increase engine compression in order to increase horsepower. The downside is that a higher compression engine requires higher octane gas, which is why race cars run 110 or higher. Putting higher octane gas than that recommended by the mfr alone shouldn't increase hp output.

Here's a good explanation of the correlation between gasoline octane, engine compression, and engine horsepower: http://auto.howstuffworks.com/question90.htm

RainMeister
'04 G35C 6MT, diamond graphite, premium, nav, aero

 

5 bucks / gallon. What a rip. =)

I think that performance wise, the effects have been pointed out or wht not. However I did not see anything about how it would help/hurt the engine in terms of how "clean it burns"? I don't know if this is just a myth but doesn't higher octane burn "cleaner" as to help not leave crap in your engine? Thats the reason I buy 91 octane..

Black / Black 2004 GcoupeMT. Premium. Splash Guardz.