I am wondering if anyone has any experience using racing fuels in their G35s. I have two stations near my new home that sell 100 + octane fuel. The attendant at one of the stations told me that various Lamborghini, Ferrari, and Aston Martin drivers routinely do half tanks with the $7 a gallon gas.

I understand the function of octane in relation to compression and spark advance, so I am really looking for any real world experience out there. Will the ECU (preferably talking about the 06 model) adjust to the octane? If it will adjust, how long will it take? Will it make any difference at all? Anyone driven a couple of tanks on this stuff.

 

i am not an expert but I would pay that much for gas. stick with 90's octain

 

You won't see any diff. in performance unless you're FI.

 

1) DO NOT RUN Leaded fuel in a car with cats they cats will clog and then disengrate... also lead fuels do a number on O2 sensors.

2) higher octane only helps if you have pre-ignition due to compression (static or otherwise).

So to answer your question, on stock compression and no FI you will see nothing other than a hole in your wallet.

and that's pretty expensive for 100 octane.

I can get 110 here for $5 / gal.. and C16 for $10.

 

Is it possible to actually purchase leaded fuel in the US?

I just moved to Paradise Valley, AZ, and I'm pretty sure this is just about the only service station in the city. It is full-service only, so even 91 octane gas pushes past $3. A day does not go by that I don't see some kind of exotic car as I leave my home on the way to work (Carrera GT, Vanquish S, GT40, etc). I actually passed 3 different Mercedes G55s once in a matter of two miles, and the Bentley Continental GT seems like it is every other garage. So, I guess the price of gas is relative.

Thanks for the info. I will not waste my money.

 

yep. i get 110 leaded at the pump.

anything higher and you have to get it from 55gal drums or so.

 

I dont fully agree with the answers given. Race fuel IMO has worked on previous cars of mine, One was FI but had NO major mods. I made an extra 6 hp on 100 oct.

 

As a motorcycle racer (pro/expert/master license; sponsored), I have used race fuel, and discussed its merits with an engine builder who works for Honda Canada.
With the pre-amble out of the way, race fuel is not actually all about octane. Race fuels do come in a variety of forms, each better for different applications, and applicable series regulations. For example, some have oxygen, for racing where it's permitted. Some have lead for where it's beneficial, but agreed on the not beneficial for 4 stroke EFI engines. Yes it is a high octane fuel most often, but super high numbers are not essential. If, regardless of whatever engine you have, the engine does not detonate/ pre-ignite the fuel, even when really hot and working hard, then a bigger number than whatever you're using to get that result, will not provide much improvement in performance. Note here: octane value falls as fuel ages, so while a pump may say 94, if the station has a low turnover, it may only be 92 for example by the time you get it, and if you leave it for a week say in a plastic can, then it will be lower still- unless it is kept in a dark, sealed, metal container (like race fuel is sold in, surprise, surprise).
So what does race fuel do so much better? Stability. There are other indices of fuel quality, but what they add up to in practice is consistent burn. The charge goes bang at the same temp and pressure each time in all the cylinders, resulting in cooler running and more horsepower (that is, reduced horsepower loss from peak due to fuel causing excessive combustion chamber temps). So it is possible to see some minor gains. Imagine if your engine is going bang at a variety of temps and pressures, and different from one cyl to another, and from one bang to the next. The mapping is trying to keep up, but the seemingly arbitrary bangs, some early, some late, cause imbalance, and crankshaft stress, and resultant heat build-up, which further causes bangs at the wrong time, so the map tries to adjust...Now imagine everything happens when it is supposed to, and the engine is allowed to turn freely. Cooler running. That's what race fuel does.
Up your compression ratio, or flash a chip to get more rpm in the remap, and race fuel will help your engine last, as well as getting the most out of it. Put on an intake, exhaust, or plenum, and you're fine to go to Sunoco and get some more 94.
Finding a station these days that has a high turnover of premium- that's the real challenge- so that you know you're actually running something close to what the pump says. Our cars will run lesser, but they won't be happy about it, and they'll let us know about it in fuel consumption and output.

Hope this helps.

Cheers,
Derek

 

I was so poor today, i put a 1/4 tank of 87 octane

I feel like such a bad father

But I had to eat....

 

there was a good thread on the 350z forums.. in the end they came to a conclusion that 1/4 100octane with 3/4 91 was the best and anymore was just a waste of $ for N/A..

just putting in my 2cents..

 

Don't ya have a nice house with a fancy garage???

 

6hp falls within the range of negligible difference.

 

U dont need race fuel unless your adding some serious timing to the motor.

 

ouch man! come onnnnnn! hahahahhahaa

i believe for turbo cars it helps a good amount~ i m not sure about N/A though!

 

negligible eh? Doubt it, when Im taking you out of a corner coming into a straight and pulling because you forgot race gas will make a huge difference....or maybe you didnt forget it, you just thought it was a waste....