Octane

[whyask]

On a otherwise N/A car.. with the basic mod list. Does it matter if you use 87 89 91 octane. I live in California and in certain areas im paying 363 wich is cheap mind you for 91 octance. I was wondering does it matter if I use 87..??

 

[the98stang]

On a otherwise N/A car.. with the basic mod list. Does it matter if you use 87 89 91 octane. I live in California and in certain areas im paying 363 wich is cheap mind you for 91 octance. I was wondering does it matter if I use 87..??

The might actually run better on 87 if you don't have a blower. But if you want to advance the timing a little bit, you need to run 91.

 

[hotstang_46]

man that's high......we recently dropped over here to about $3.20 for 91..... we've recently been close to $4.00 though....


Only thing I know, my kawi zx10 makes more power on 87 than 91....

wouldn't think it would matter unless you have a tune specifically for a certain octane...... maybe you'd want to stay away from "lugging" the car at very low rpm's though with a lower octane

 

[whyask]

ya I have the basic bolt ons no tune yet so ......

 

['13_ImpactBlue_GT]

man that's high......we recently dropped over here to about $3.20 for 91..... we've recently been close to $4.00 though....


Only thing I know, my kawi zx10 makes more power on 87 than 91....

wouldn't think it would matter unless you have a tune specifically for a certain octane...... maybe you'd want to stay away from "lugging" the car at very low rpm's though with a lower octane

Damn!!!!!

91 is 2.70 to 2.80 here

I was running 87 till she started pinging really really bad (95 degrees + and humidity = 105 degrees). On my 2nd 91 oct. tank the pinging has been greatly reduced

 

[kylebgt]

Mine loves 89.
If you wanted to save alittle $$, 87 is fine for a near stock car. 91 may be alittle bit overkill. Remeber all octane ratings mean is how much the fuel can be compressed before igniting, 91 and > fuel is only needed for higher compression engines. Where I live 89 is cheaper than 87 since it contains an ethanol blend.

 

[mustanggt3685]

+1 on all accounts. I started to use 91+ in my GT after tuning it with a superchip (advanced the timing) and it did make a minor difference. Usually if you get a tuner or chip, it will tell you when to up the octane depending on the tune.

 

[the98stang]

Usually if you get a tuner or chip, it will tell you when to up the octane depending on the tune.

If you advance the timing AT ALL, you should use 91+ to prevent detonation.

I feel bad for you other cali guys...I pump 91 for 3.15 at Chevron. I guess the bigger the city, the higher the price