i have an 02 z28. there is a serious gas shortage in phoenix, az, and literally no stations have 91 octane. the few that have gas at all is 87 octane and it's an hour wait at $2.50 a gallon. anyway, i have 1/3 a tank of 91 octane now. if it gets near empty, can i still put in 87 octane in my car? it is 110 degrees in phoenix so i'm not sure if this is safe at all for my car.

 

IMO, fill up now while you've still got some 91 in the tank to mix with the 87, but as long as you don't drive the car hard (knowing you've got 87 in there, hopefully you won't) then NO, there shouldn't be a problem. The beauty of fuel injection and having a knock sensor is that the computer will retard the timing automatically if it senses any pinging. If all you can get right now is 87, that's fine. I ran on it for the first few months I had my car (financial reasons more than anything at the time ) and it's fine IMO. Just don't hammer on it too much or expect to do any racing (FWIW, the Owner's Manual says that 87 is acceptable).

 

Can't you just mix in some octane boost?

They ran out of 91 octane at some stations here, and on the news they say our oil is being brought in from Arizona.

 

if you run 87 better run some good octane booster also i have seen cars get detination on 91 stock so if you plan on hitting that gas pedal get the octan up high. I personally never run less then 93.

 

#1.. he'll have to use lots of octane booster to get it anywhere near 91...

#2.. If you want to up the octane Use.. what the heck is that stuff called.. toulene? i forget, but the turbo guys use it to up their octane and its safe for your engine... Its sold at paint supply stores. Do a search i'm sure its been discussed on here before .


And cap pete is right, if you don't get on it at all. 87 will do you ok

 

I just thought about something maybe you could order somne vp fuel or sunoco race gas for cheaper then what you could get 91 right now see if you could order it by the drum

 

Now thats an idea

 

All the octane boost I see use one bottle to treat around 15 gallons and say they increase the octane rating by up to 7. Even half that would be 3.5. 3.5+87=90.5 But 87 would be ok to use, if you get tired of going easy on your car though, you could buy some octane boost.

 

Unless you are using some brand unavailable on the east coast its

0.7 points!

Eric

 

As long as you take it easy you should be ok. the computer is retarding the hell outa your timing with 87 octane.

 

At least it's capable of that though. An old style carb'd, non-EFI car would be pinging like crazy!

 

OK OK, so how does octane booster work like that? If its supposed to raise it 7 pts, why does it raise it 0.7?

 

learn chemistry

 

OR read this http://members.tripod.com/racerjoe/c...e_booster.html

that'll explain it better than i.. and again refer to my suggestion of buying toluene.

Eric

 

the problem with the computer retarding the timing is it requires the spark knock to first retard it and some spark knock to keep retarding the timing. overall bad. 87 octane with one bottle of outlaw or nos octane boost will take care of it fine.