This may sound dumb, but the last Z I owned was a pretty ragged '84 while I was in college ten years ago...
Now, for those of you who don't drink or who were fortunate enough to receive a sizable stipend while in school, you won't recognize my college budget, but it went something like this...
For every 20 dollars I had, 82 cents went for food, 1.03 for gas, 6 cents "miscellaneous", and the other 18.09 went for beer.
So that poor, run-down 84 (it had Nissan on one side of the back and Datsun on the other...sigh) never drank anything richer than 87...
So, now that I only spend 18 of every twenty FIVE dollars for beer, I was wondering if 89 octane is ok or should I use 93 every time I fill up the new Z?
I welcome your comments/feedback.
Cheers.

 

Well I believe the owners manual says 91 or higher. So I would try to keep it above that. The Z has a high compression engine that it requires higher octane to reduce detonation. Spend the extra $4 at fill-up and you will have a nice sense of security.

 

The engine was designed and tuned for 91 or higher. You can use 87 or 89 and let the detonation sensor detect knock and back down the ignition timing (read: half-assed idea) or you can lower your base ignition timing (read: more sensible idea).

However, you will lose hp if your ignition timing gets bumped down.

Michael.

 

...It's kind of sad that even though it's a car forum, your thread gets read 1,000 times if it has "*****" in the title, and 26 times if it just says "octane"...
Only one thing we like more than cars, obviously.
Thanks for your input guys, I figured the better gas would be; well; better.

Cheers.

Trout

 

The only fluid to touch my Z's lips has been Sunoco Ultra 94.

 

What about some of the stations that sell 94+ octane. I know they are few and far between, but is the higher octane reccomended? Does it provide better performance?

 

NO, NO, NO!!! Do not put Turbo Blue or similar in your car. You will fry your cats, maybe your engine, and be very sorry.

Octane controls the speed at which gas burns. This car requires the burn rate that 91 octane provides. Anything above 91 is pointless unless you advance your timing a little. You may actually lose power with higher octane! If the gas burns too slow, it will be exiting through the exhaust valves before it is completely combusted, hence the fried cats and lost power.

-TB

 

Not entirely true.

It is quite possible to gain hp from using a higher octane fuel if the ECU already has the fuel & timing maps for that higher octane level; I'll be willing to guess that many hi-po cars these days have those maps. And you may gain even more if you advance your base timing.

Furthermore, octane is merely a measurement of a fuel's resistance to spontaneous ignition. I shall defer you to part 3 (of 4) of the Gasoline FAQ: http://www.cs.uu.nl/wais/html/na-dir...faq/part3.html Go to 6.2 "Why do we need octane ratings," second paragraph.

Michael.

 

Good read, but you should have read further - to section 6.13. The way the ECM works is to back off timing if knock is detected. Timing is NOT advanced if knock is NOT detected. You need to do that manually, within reason, to get some more power.

That said, I'd like to see dyno runs on 91 and 94 anyway.

Thanks for the link. I can't get enough of that stuff. What a geek I am.

-TB

 

Dangit, how did I miss that one (yes, I've read part 3/4 completely)? It must have been that SCC article where they dynoed 244rwhp on 91 octane and 249rwhp on 100 octane.

Anyway, even if 94 octane doesn't give you more hp than 91 octane, 94 octane shouldn't damage the emissions system.

Michael.

 

maximas are known to lose performence running octane that is lower than 91. We got the VQ since 95, a lot of people says that running below 91 will make knocking and lose power.

 

Right! I was warning people to stay away from that 100+ octane stuff you find at some gas stations. I have one just around the corner that sells Turbo Blue @ 103 octane. $4.00/gallon keeps most curious people away! High compression race engines - yes, emission legal street cars - no!

-TB

 

OK Guys help me out here.

I live in Japan, and Purchased the Fairlady Z, yes same model
called 350Z in the states. Gas in Japan "regular" is 93 octane
at all stations, with premium at 102 and 103 oct. Gas is Japan is very expensive about $40.00 a tank. I can buy gas on a U.S. base here for the same price in the U.S. about $20.00 a tank, but the octane on base is about 89 no other choices. They do sell
products like Octane boost. Would you recomend but cheaper gas and inputing Octane boost?

Thanks

 

I used to run 103 octane turbo blue in my bike and it worked well cause my CBR ran better when the engine temp was up.

some Sunoco stations sell gt100 unleaded, sometimes sold as CAM2. Check the label carefully when filling up to make sure you get unleaded.

 

Some on this board have noticed increased power with octane over 91. Don't know if this has been tested on a dyno yet.

 

try this url to find 100 octane gas
http://www.racegas.com/Racegas/gt100locals/default.asp