Well then 93 it is. That and fuel injector every once in a while

Just dropped off my new Z to get its clear bra and windows tinted.

Have you tried putting 87 in your car? I did try, not on my Z of course. It did give less mpg and stinky exhaust.

Shrug. The only big difference in 87 and 93 is just the octane rating. Some brands use a different additive pack in their premium. Could account for the smell I guess. Catalytic converters burn up anything fuel wise that's left over so it wouldn't be that.

Several years ago I test 87, 89, and 93 in a cross country road trip. This was in a car spec'd for 87 and I got the best gas mileage from 87. Ran two tanks of each fuel to be sure.

Bottom line, just use what the car is spec'd for. With 11:1 compression in the Z motor, premium is your best bet.

Gonna need some pics...

I can't stand clear bras (on cars). What's the cost of that service? the only rock chips my car has are on the front bumper and I can get a quality respray on that for around $300 through a friend connection.

Well, good for you and your friend. Opinions are like ********...but it's my new car, not yours. I fought hard to get my 370Z. It's my first new car and I want to keep it looking great for a long time. I don't live in Jerkwater USA. I have to daily-drive on SoCal super highways and it sucks. I don't want to re-spray my front bumper every year. To me, that's a hassle.

It was $800 for the clear bra + $200 for the tint.
It took all day. They wrapped the hood. I can't even tell it's there. They even gave me a bottle of XPEL wax for the clear bra. 3 weeks ago I didn't even know what a "clear bra" was....not until I did my research here on the forums. An overwhelming amount members recommended a clear bra for a daily-driven Z.

I took iPhone photos at sunset, so the 35% tint appears darker. Thanks to the forum, I was able to warn the shop about the infamous peeling that so many Zs encounter on the front windows.

Can't even see it bud! If you live in an area with a lot of debris on the road it's not a bad idea.

In the context of the thread, 87 vs 91+ is irrelevant, as GTI's also prefer premium fuel too. ;)

The past 5 cars I've owned have had premium-fuel requirements. This topic always comes up in enthusiast forums when gas prices start to rise. Frankly, I really don't understand those who try to "sneak by" with cheapening out on running regular grade gas in a 'premium-recommended' car. I mean, it's your car, so do whatever you want. And yeah, it'll usually be 'ok' to run regular unless Premium is required, like in the case of a WRX STi. But MPGs are far more dependent on the driver, temperature, & wind than on octane. I suspect that achieving better MPG on 87 would be from the driver intentionally being easy on the gas pedal ("it's ok to run 87, just don't accelerate hard") rather than from the gas itself.

But look at the economics...

The price of premium should be .20-.30 /gallon more than the cheap stuff. At least, that's been the case everywhere I've ever filled up one of my cars, whether at home or traveling. Some stations do gouge more for premium (one in my town charges + $.50/gallon more than regular :shakes head:), but they are (IMHO) the exception, not the rule.

So let's assume you're filling up with 17 gallons. Assume 87 is $3.50, 91+ is $3.70. You're spending $59.50 on 87, or $62.90 on 91+. A difference of $3.40 or 5.4%. I get it that $3.40 is $3.40. Times are hard, and every dollar counts. But if that extra $3.40 over the $~60 it cost to fill up is that much of a strain on your budget, then you've got bigger problems than whether or not to put premium in your car. Go buy a Prius. ;)

Furthermore, the higher gas prices go, the less expensive relative to regular that premium becomes, assuming that $.20 difference remains. At $4 for 87, $4.20 for 91+, you're still paying just $3.40 more than the guy filling up with 87, but that's 4.7% more ($68 vs $71.40) . If 87 hits $5 and 91+ hits $5.20, now you're just paying 3.8% more for premium ($85 vs $88.40). And so on. Hey, I know it's of little consolation when gas hits $5/gallon this summer, but it's mathematically correct.

Is saving those few dollars a fillup really worth worrying about damage and/or limiting the performance of your car?

Now, if premium gas suddenly becomes $.50, $.75, or $1 more /gallon than regular, or if you live in an area where premium is significantly more than regular, then the economics of the question become much more meaningful.

^^^^ Very good points. All of my cars require premium as of today and I've always calculated as you have above. Costs me about $4 per tank difference over 87 for 93 octane where I live, or $2 a week LOL

:yum:

And yeah... wish I had known about the tint issue. I've got the corner peel on both windows.

Maybe it's my area, but the gap between regular and premium gas seems to have widen a bit at most gas stations. The 20 cents difference doesn't seem to be norm now. I am seeing 30 to 40 cents at most major gas stations. It's one of the reason why I get gas at Citgo and Sam's

Can you point me in the direction of this info? Tint is on my short list.

http://www.the370z.com/exterior-inte...ing-issue.html

It's a sticky under the Exterior/Interior section of the forum.

^^ Thanks. I thought this was some issue with a piece inside the door. The windows going up and down when the door is opened is pretty standard now. My Challenger does the same thing. Never had a problem with that tint and the guy does all my cars. I'll let him know just the same just in case about those corners though.