Premium Fuel

kloh · Mar 19, 2003

So, in order for the car to operate at peak performance it needs premium fuel. With gas prices skyrocketing (it's getting close to 3 bucks for premium here in SoCal), has anyone else considered using regular for this bad boy? What are your experiences? How much worse is the HP/mileage? I've read that the G35's engine doesn't live up to it's published MPG of 19/25 until after a few thousand miles anyways so I wonder what the harm would be in feeding it some regular occassionally if I'm not that interested in racing performance. Anyone have firsthand experience with this and can you confirm which type of fuel you've been using?

I know I'm gonna get blasted for this one so if you are so inclined, go right ahead and tell me how stupid it is to put regular fuel into this highly sophisticated piece of equipment, and that the incremental cost should not even be a factor, or why bother getting this car if you're not going to redline it -- but what I'd rather hear is, some real facts from someone who's tried it.

Let the onslaught begin...

-Ken [dunce]

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impatiently waiting for my Diamond Graphite...

Semi On · Mar 19, 2003

RTFM.

It says to never put anything other than premium unleaded in the engine.

The sedan can apparently alternate between premium and the middle grade gas but mileage will suffer.

If you deviate from this, you do so at your own peril!

Gardiner · Mar 20, 2003

Running regular in our sedan. The G35 sedan gets worse gas mileage than my C5 vette, in town or on the highway.

2003.5 Blue Sedan

kloh · Mar 20, 2003

I'd RTFM if I had one... still waiting for my G to arrive, and the waiting SUCKS! [banghead]

Any idea what's different about the sedan engine that allows it to alternate that the coupe doesn't have? The only difference I'm aware of between the engines is that the coupe has more HP than the sedan.

-Ken

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impatiently waiting for my Diamond Graphite...

Gardiner · Mar 20, 2003

could be compression ratio or tuning.

2003.5 Blue Sedan

xzellerate · Mar 20, 2003

I use Amoco Clear Ultimate Premium. In Miami all we get is 93 octane. Is this good enough?

XL

2003.5 5AT Sedan Ivory Pearl/Graphite Leather Sport/Premium/Aerokit

kloh · Mar 20, 2003

Gardiner,

What MPG are you getting on your sedan?

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impatiently waiting for my Diamond Graphite...

Gardiner · Mar 21, 2003

About 23 mpg on the highway.

2003.5 Blue Sedan

kloh · Mar 21, 2003

That's not bad considering it's only supposed to get up to 25mpg on the highway.

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impatiently waiting for my Diamond Graphite...

Chaz · Mar 21, 2003

Yeah I'm averaging around 22 highway and 17 city...

'03 G35 Sedan.

kloh · Mar 21, 2003

Chaz, you using regular or premium?

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impatiently waiting for my Diamond Graphite...

twinpeaks · Mar 21, 2003

93 octane is the way to go...would never put anything else in any of my cars (unless it's a rental!). [boink]

Jedi · Mar 31, 2003

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by twinpeaks

93 octane is the way to go...would never put anything else in any of my cars (unless it's a rental!). [boink]
<hr height="1" noshade id="quote"></blockquote id="quote">
Why I'd never buy a rental car! [

]

"Use the Forced Air Induction Luke"
-Jedi

Jedi · Mar 31, 2003

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by kloh

So, in order for the car to operate at peak performance it needs premium fuel. With gas prices skyrocketing (it's getting close to 3 bucks for premium here in SoCal), has anyone else considered using regular for this bad boy? What are your experiences? How much worse is the HP/mileage? I've read that the G35's engine doesn't live up to it's published MPG of 19/25 until after a few thousand miles anyways so I wonder what the harm would be in feeding it some regular occassionally if I'm not that interested in racing performance. Anyone have firsthand experience with this and can you confirm which type of fuel you've been using?

I know I'm gonna get blasted for this one so if you are so inclined, go right ahead and tell me how stupid it is to put regular fuel into this highly sophisticated piece of equipment, and that the incremental cost should not even be a factor, or why bother getting this car if you're not going to redline it -- but what I'd rather hear is, some real facts from someone who's tried it.

Let the onslaught begin...

-Ken [dunce]

-------
impatiently waiting for my Diamond Graphite...
<hr height="1" noshade id="quote"></blockquote id="quote">

According to the salesperson at the dealership..(which I think he practiced this speech at home in the mirror because of the increased questions due to the rising fuel costs) he states the u can use reg.unleaded but it will reduce the performance by 15-20% overall. He states that it will NOT void your warranty. Hence the words RECOMMENDED . But my thinking is, if your so damn cheap you can afford to put premium in your baby you should have bought an econo car and called it a day. [

]

"Use the Forced Air Induction Luke"
-Jedi

kloh · Mar 31, 2003

<blockquote id="quote">quote:<hr height="1" noshade id="quote">But my thinking is, if your so damn cheap you can afford to put premium in your baby you should have bought an econo car and called it a day. [

]<hr height="1" noshade id="quote"></blockquote id="quote">

I know, I know... for the record, I'm using premium because a Prius [xx(] wasn't on my short list when I bought this car. I just wanted to know if anyone actually put the regular stuff in and how much performance/mileage loss they experienced.

-Ken

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2003 G35C
5AT | DG + Willow Leather | Nav | Premium | Performance

tmartin316 · Apr 1, 2003

is it just me, or does the octane rating have NOTHING to do with the performance level of the car? the only difference between regular and premium is the octane level. the compression ratio of the engine determines what octane you need to use, higher compression=higher octane....the reason for this is that if you have high compression, you need the higher octance to supress or eliminate pinging, or knock, which is seriously damaging to the engine. a ping is when the low octane gas is compressed too far and it detonates before the piston reaches TDC(top dead center), which forces the piston against the direction its rotating. this is very damaging to the engine, namely the crankshaft, which can snap if it is subjected to enough abuse...and at 6000 rpm, thats more than enough damage.

so please, dont use anything less than premium if the manual says premium, no matter what the cost of the gas, because the cost of the gas is FAR less than what you will pay for an internally damaged engine.

Patiently -- or not so patiently waiting to trade in my 1996 I30 for a wonderful G35 SC!

bslote · Apr 1, 2003

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by tmartin316

is it just me, or does the octane rating have NOTHING to do with the performance level of the car?<hr height="1" noshade id="quote"></blockquote id="quote">

If you put lower octane gas in a car, it'll knock. This won't damage anything, because the car detects that and retards the timing to prevent knocking. You'd think that it'd be hard on it before it caught it, but it isn't. The retarded timing is what causes the reduced performance, making it especially sluggish from a stop, but also hurting top end. So all putting lower octane gas in the car does is cause the engine to run very inefficiently with less power and fuel economy since you're running a high compression engine with retarded timing, which is worse than a lower compression engine with proper timing.

Gbye40Gs · Apr 1, 2003

I use only 94 octane from sunoco the ultra shit. Its only four cents cheaper and on a 20 gallon tank that is a bank breaking 80 cents. I love it but i still get shit for city miles but ohhh well thats part of owning suck a beautiful machine that begs to be driven hard!

6MT-Brilliant silver
aero, premium minus nav
ohh dont forget the trunk
mat LOL!

tmartin316 · Apr 2, 2003

what I said earlier I did not actually say, it was my friend with the SI, I dont know near as much as him about cars, but its obvious that neither of us know as much as most of you guys (or at least remember), and he says (as a reply to yours bslote)

"Yea, you are right, I had forgotten about the new technology, like the ping sensor, etc....."

so yea, there you have it. Good call bslote.

Patiently -- or not so patiently waiting to trade in my 1996 I30 for a wonderful G35 SC!

kloh · Apr 2, 2003

It just cost me over $42 to fill up with 91 octane!!! And I still had about 30 miles to empty.

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2003 G35C
5AT | DG + Willow Leather | Nav | Premium | Performance

Premium Fuel

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