For a supercharged car (running about 8 PSI) with no cat, is there any advantage to running leaded fuel? How about any problems?

I am drawn to the idea of running leaded fuel since you can get it in higher octane levels than unleaded. I am currently running VP 103, but was considering running the VP 110 leaded.

-YS

 

Unless you need an octane level that is not available with unleaded, there is no advantage. Are you having problems with detonation?

 

I am not having a problem with detonation at 103. I guess my hope was that with 110, I could tune a tad leaner than I have tuned with 103. Since the fuels are the same cost and I won't have a cat, I thought it made sense to run the one that would allow me to tune for maximum performance.

-YS

 

"Lead" addititive, tetraethyllead, is a great octane booster but produces lots of toxic byproducts and ruins catalytic converters.

As Chris pointed out, if you need to check pre-ignition/detonation, don't have a cat, and don't care about the lead oxide residue from leaded fuels, it might we worth trying.

Running higher octane fuel if you do not have preignition accomplishes nothing, however.

The lead addititives also had some lubrication properties, but modern engine designs and fuel compositions have eliminated the need for it.

 

[QUOTE]Originally posted by Yellow Streak
[B]

I am not having a problem with detonation at 103.

 

Leaded fuels are also easier on valve seats.

 

That is an old belief that has been proven dated. After lead was phased out many were worried about valve seats that were not hardened but it turns out tests with old seats and unleaded gas proved there was no problem.. so maybe it was just a story by those not wanting to give up leaded fuels. Todays seats are all designed for a full life with unleaded fuel so it should not be a consideration.

 

Won't the leaded fuel ruin the 02 sensors as well? I know you are running without cat, but you still have the 02 sensors in I would imagine.

 

[QUOTE]Originally posted by RWD_RCKT
[B]Won't the leaded fuel ruin the 02 sensors as well?

 

[QUOTE]Originally posted by RWD_RCKT
[B]Won't the leaded fuel ruin the 02 sensors as well?