impaled

i just got my 1996 gt last week and i filled it up the night i drive it home with 87. the next day the seller randomly calls me and he says that he uses premium, im just like whatever. so i take it out and really jump on it for the first time (i didnt jump on it the first night b/c i drove it home w/no plate)and it was pinging. so i bought some octane booster, poured it in and it stopped pinging. im about to fill up again and i am just curious whatoctane you stock gts are running.i had a 1989 5.0 and it was fine with 87 and im just surprised that 87 isnt enough for my 1996 4.6. thanks for your feedback in advance.

HOLLYWOOD99

91, with a 10 to 15% ethanol content.

Unfortunately its the best $hit they sell here in AZ.

If anyone knows of any thing better (aside from going to a race shop and getting fuel) let me know!

yourmom6990

you run 91 on a stock engine?
i run 87. no problems at all.
stock engines arnt made to really handle higher octane unless they have a proper tune.
i read somewhere on here, that in some cases you acctually get worse gas milage, and your car doesnt perform at full potential.

rainydayracing

I run 87, but I'm an 02...unless your car is tuned for 91+, you should run 87.

xcodegt

nothing but 93 here in ga. High heat makes the intake charge warm enough, even without the heat soak from the engine, so 93 is almost mandatory. some of my associates run 89 octane, but nothing less

97mustang17

91 or better, only because i have the diablo tuner and its a 91 octane tune. otherwise the motors are made to run on 87

MoKo_04GT

93 octane here. tuned for 91+

Jakes

Unless your car is tuned (timing bumped) or your running a power adder, you should be able to run 87. Run the lowest octane you can without knocking or pinging. Anything higher and you're wasting your money.

96GT226410

In my '96 I used to run 87. When I get done with the PI swap, I'm going to run 93 most likely, unless I can get away with 89.

GThopeful

I have ran nothing but 89 since I bought the car 9 months ago.