xL8 APEKSx
NAXJA Forum User
- Location
- Garden Grove, CA
BG44K...search online. It's hard to find in stores, though shops or dealerships usually have it on hand.
As for the fuel...I usually own at least one boosted car (turbo or supercharged). Right now, I have one of each (Corrado with a S/C and Volvo with a turbo). I run high boost in both of them, and I have always used toluene to raise the octane. It's easy to calculate the effective octane; you add up the total amount of 91 in the tank and the total amount of toluene (114 octane r+m/2), and divide the total by the number of gallons in the tank.
I would mix up to 30% toluene with 70% pump premium (91 here). However, this was just to fight detonation when running 20+psi. Since I drive the piss out of these cars and only mix the special brew for racing, I have never noticed any increase in fuel economy.
My 4.0L has 75k on it, and runs well. I don't think there's much gunk on the inside. It's had it's share of cleaners passed through it.
If you really want to increase MPG that badly, make a front airdam or a bellypan to help the aerodynamics. If your car sees any freeway miles, this would make at least as much of a difference as the acetone, if not more.
I picked up over 1mpg (over 20 miles per tank) on my Volvo by putting a sheet of aluminum under the rear of the car, no other changes made. Looking at how uneven the underside of the XJ is, I'm pretty sure you could see a substantial gain here.
As for the fuel...I usually own at least one boosted car (turbo or supercharged). Right now, I have one of each (Corrado with a S/C and Volvo with a turbo). I run high boost in both of them, and I have always used toluene to raise the octane. It's easy to calculate the effective octane; you add up the total amount of 91 in the tank and the total amount of toluene (114 octane r+m/2), and divide the total by the number of gallons in the tank.
I would mix up to 30% toluene with 70% pump premium (91 here). However, this was just to fight detonation when running 20+psi. Since I drive the piss out of these cars and only mix the special brew for racing, I have never noticed any increase in fuel economy.
My 4.0L has 75k on it, and runs well. I don't think there's much gunk on the inside. It's had it's share of cleaners passed through it.
If you really want to increase MPG that badly, make a front airdam or a bellypan to help the aerodynamics. If your car sees any freeway miles, this would make at least as much of a difference as the acetone, if not more.
I picked up over 1mpg (over 20 miles per tank) on my Volvo by putting a sheet of aluminum under the rear of the car, no other changes made. Looking at how uneven the underside of the XJ is, I'm pretty sure you could see a substantial gain here.