Subaru Enthusiasts Car Club of the Sierras - View Single Post

sperry · 2007-05-15, 08:42 AM

Mike Warfield has instructed me (on many occasions) to run 4-5 gal of race 100 per tank of 91 in my car.

It's not just for the "safety" boost in octane over 91, it's also because pump 91 can actually be 90, 98, 87, who the hell knows... quality control ain't nearly as good for the 91 at the pump as it is for race 100 out of a can. How many people have heard the phrase "I must have just gotten a bad tank of gas"? Tossing 1/4 to 1/3 of a tank of 100 in there may bump the octane "uselessly", but it may also turn that tank of 90 you accidentally got into 93 and save the day.

A few gallons of 100 is good insurance, even if it costs you 3 or 4 hp.

2007-05-15, 08:42 AM	#17
sperry The Doink Real Name: Scott Join Date: Nov 2002 Location: Portland, OR Posts: 20,335 Car: '09 OBXT, '02 WRX, '96 Miata Class: PDX/TT-6 The way out is through	Mike Warfield has instructed me (on many occasions) to run 4-5 gal of race 100 per tank of 91 in my car. It's not just for the "safety" boost in octane over 91, it's also because pump 91 can actually be 90, 98, 87, who the hell knows... quality control ain't nearly as good for the 91 at the pump as it is for race 100 out of a can. How many people have heard the phrase "I must have just gotten a bad tank of gas"? Tossing 1/4 to 1/3 of a tank of 100 in there may bump the octane "uselessly", but it may also turn that tank of 90 you accidentally got into 93 and save the day. A few gallons of 100 is good insurance, even if it costs you 3 or 4 hp. __________________ Is you is, or is you ain't, my con-stit-u-ints?