Leaded fuel and catalytic converters

[Rockrawl]

So I have the Bronco loaded up on the trailer to go wheeling in the am and remember that I haven't put any gas in it in a while. So I go to the garage, grab a 5 gallon gas can that's about 2/3 full and dump it in the tank. About the time I finish I remember that that particular can had 110 octane, leaded fuel in it from a sandrail that I recently sold. So, my question is how bad is lead for cats? Do you think that the 3-4 gal that I'm gonna burn is a big deal, or I just shouldn't do it again. I would really hate to drain the tank and start over. I will top it off in the morning with regular gas to fill up the stock tank.

 

[Broncobowsher]

Hard to say. Race gas is usually high in lead, much higher then say 100 octane LL slow burn AV gas. I have heard of old days where one load of mexican leaded gas would kill a cat, but also have seen modern cars take race gas and live just fine. So will 3 gallons of leaded race gas hurt the cat. I can't way it won't, but I will say probably won't based on what I have seen at the track. By the time you dilute it with whatever you fill the tank with.

I would say just leave it. The worst it could do is hurt the effiency of the cat, it won't clog it.

What is a '72 doing with a cat anyway?

 

[broncnaz]

I agree as long as you dilute the 110 with some unleaded you should be fine. I dont remember seeing Cats on your rig although its been awhile. Did you put some on? Are they aftermarket types? If they were there when we tweaked your carb and its been running fine since I dont think a couple gallons of leaded fuel will hurt much.

 

[Rockrawl]

Thanks! That's what I was hoping to hear...seems right to me too

I've had several other vehicles with just a cat and no muffler and they have all sounded pretty good. And when I bought this truck the PO had a cat for it but no exhaust system. So when I had the exhaust system made up I just had them put the cat in for noise reduction and to save me some $ on a muffler. It actually sounds pretty good so I haven't got around to switching it for anything else. It is just clamped in though so it will be easy to change one of these days....or tomorrow if it starts running like a$$

I don't think it had an exhaust system when you helped me with the carb...maybe just headers...or maybe the POS system that was bailing wired on there when I got it Now it has a 2.5" into 3" with a single 3" high-flowcatco cat

Thanks again guys,
Tyler

 

[broncnaz]

Yeah I cant remember it was a while back and we were looking at the other end of the system. I know you hadnt had it long when I helped you out.