octane booster...
Use Torco Mach Accelerant. You can get it in 104 no-lead or 110 leaded. I had to use the 104 no-lead in my Omni and it's the only stuff that ever worked. Anything else I tried just resulted in ball-peen hammer on block sounds from under the hood at WOT.
Yes, it is .5.
Most octane boosters are not worth it in small quantities, and are too expensive for large quantities. I prefer some 100 even if I carry 3 gallons and put it in right before a race.
Toulene is a great octane booster but here in NorCal it's going for like $13/gallon
Unical 100 is $4.59 a gallon nearby.
Jim






