Race fuel?

[MARKP]

So the only disadvantage of leaded fuel is fouling O2 sensors?

In cars designed for unleaded, that is definitely not the only disadvantage. You will foul the O2 sensor in a hurry, the catalytic converters will also clog up. Those are definite issues. Other things that I would suspect could happen would be killing other sensors that are in the exhaust, possibly those in contact with oil, and fouling the spark plugs.

[ke0ki2k]

So the only disadvantage of leaded fuel is fouling O2 sensors?

In cars designed for unleaded, that is definitely not the only disadvantage.

yeah, like the O2 sensors in your header...that help your engine tune for the fuel....so youd be up shits creek basically Lucas

[rheacerdave]

^ True
Also, if your car is tuned for 93 octane, unless you can adjust carb/ timing or remap computer, no advantage at all, but more costly.

Um, I used turbo blue leaded with EFI in my old SPO Mustang Fox body- no cats. Ran fine, although you could see grey build up on the sensor tips. It was a dedicated race car, so O2 sensors were not a factor at WOT. Idled OK, too, though. Wasn't road legal-didn't even have headlights.
Finally changed out for some Bosch sensors after a couple of seasons just to be safe.
Put 3 gallons of race fuel in my 03 Cobra daily driver by mistake- Had 2 containers the same color- a year or so ago. Kept getting ck codes for "Cats not at full efficiency", but still ran good. After I ran it a couple of months, stopped getting codes. It was a pain with it coming on (like 4 times in 2 months.) Advance guys would check and reset for me for free, but not something I would not do again.
for anyone thinking of using octane boosters:
http://www.europeancarweb.com/tech/0503 ... index.html
A/Sedan, we have to used leaded with die electric # of "0", so this chart helps, too
http://www.smithtex.com/racing/fuelcomp.html

[ke0ki2k]

^ True
Also, if your car is tuned for 93 octane, unless you can adjust carb/ timing or remap computer, no advantage at all, but more costly.

Um, I used turbo blue leaded with EFI in my old SPO Mustang Fox body- no cats. Ran fine, although you could see grey build up on the sensor tips. It was a dedicated race car, so O2 sensors were not a factor at WOT. Idled OK, too, though. Wasn't road legal-didn't even have headlights.
Finally changed out for some Bosch sensors after a couple of seasons just to be safe.
Put 3 gallons of race fuel in my 03 Cobra daily driver by mistake- Had 2 containers the same color- a year or so ago. Kept getting ck codes for "Cats not at full efficiency", but still ran good. After I ran it a couple of months, stopped getting codes. It was a pain with it coming on (like 4 times in 2 months.) Advance guys would check and reset for me for free, but not something I would not do again.
for anyone thinking of using octane boosters:
http://www.europeancarweb.com/tech/0503 ... index.html
A/Sedan, we have to used leaded with die electric # of "0", so this chart helps, too
http://www.smithtex.com/racing/fuelcomp.html

Thanks for the info, its not going into the car though its bound for a 2-stroke kart engine.

[lcoleman]

So the only disadvantage of leaded fuel is fouling O2 sensors?

In cars designed for unleaded, that is definitely not the only disadvantage.

yeah, like the O2 sensors in your header...that help your engine tune for the fuel....so youd be up shits creek basically Lucas

They'd be offset from the main exhaust flow by defoulers, and I wouldn't have cats at all. You do raise a point about the O2 sensors helping the engine tune for the fuel, but I'd say they're used to tune injection/mixture, while the knock sensor is constantly being used to adjust timing on the fly.

Either way, it's not something I was actually seriously considering trying...I'm just armchair modding.