octane

[97yelstang]

i just did a pi headswap on my car about 6 months ago... and ive been running 92 or higher octane in it with no problems....but i was wondering if i could get away with running 89 octane??
btw i have a 160 degree thermostat
thnks for any info

 

[san~man]

If you haven't advanced the timing, you can try a lower octane (although the PI swap results in a slightly higher compression than a reg. PI motor). I would do a half tank and see if you get pinging.

If you do, you would be better off going back to the super.

 

[TweekedGT]

Mine never really ran great on 89 after the headswap. I had done cams at the same time as the swap though.

 

[four six]

Yeah I have just been running 93 all the time. I wanna be able to go WOT and not "really" worry too much.


But I also did cams and advanced the timing.

 

[Mustang5L5]

Ditch the 160 t-stat and put a stocker back in.

 

[97yelstang]

the t stat is what came with the hypertec chip

 

[Superhereaux]

160 is extremely low


unless your commute to work is at least an hour long mostly sitting in traffic with the a/c on or you're at wot between every light the engine isn't getting near hot enough, and even then

 

[san~man]

180* is generally the lowest acceptable t-stat recommended.

 

[the98stang]

The PCM operates at its maximum performance at normal operating temp with the 190^ Tstat. Therefore the car will run its best with the stock Tstat. I would keep it that way.