Any other "side effects of Leaded fuel?

[nona.M]

So my dumbass got all excited last week cause I found racing fuel, 110 octane, and wanted to mix it with 91 octane to get the mix of 93 octane. I ended up mixing 2 gallons of 110 with 17 gallons of 91 which should yield me the 93 I was shooting for.

I went back yesterday to fill up again but realized the 110 octane is leaded fuel!! and decided not to do the mix again.

I've been looking around but have only found that using leaded gasoline can mess up the o2 sensors and the cats, are their any other things it can mess up? is my engine safe? should I not do the mix again? I live in AZ so 93 is not an option over here, was surprised when I found the racing fuel to be honest.

[DCaff300ZX]

That's news to me regarding O2's and cats with leaded fuel, any reasons given why? Maybe post your source?
To my knowledge the only real issue is higher compression needed for crappier fuel (lower octane) which means that detonation can be had easier in boosted apps using a higher compression ratio...why the TT uses a lower comp ratio than NA.
I have occasionally used the fuel additives and leaded fuel trying to get the higher octane, but never really found any difference in the TT and minimal change for my NA, and have also read that mixing does not actually increase/change octane accurately, or even at all. You basically want the fuel at the necessary octane already.

[nona.M]

I've read it in a few honda prelude forums, preludepower and preludeonline if im not mistaken.

so if I "felt" any difference or the Z running smoother it was all in my head??
looks like I'm stuck with 91 octane in the mean time

[NolimitZ32]

Leaded fuel will damage O2 sensors and Cats over time, running it a few times wont hurt anything. There is ABSOLUTLY NO NEED to run high octane fuel in your car, there is no benefit from it no matter what anyone has ever told you. Your car is tuned from the factory to run on 91 (R+M)/2 <standard octane number used in US. If you run lower octane you ruin the risk of pinging at WOT in hot weather. Your car will compensate up to a certain point so realistically if you don't WOT the car you could run your Z on 87 all day and not hurt anything (not recommended but possible if needed). Your car WILL NOT adjust up to make use of the 110 or whatever octane you are trying to run, it will read that there is no knock at the highest timing value in that specific map and run happily at factory setting while you are wasting money paying $12/gallon on 110 octane fuel.

[Rogue One]

↑ ↑ ↑ This!!!

[DCaff300ZX]

I had to run a tank of 87 once in my NA from out of town 200 miles, it was all they had and I was on "E", and disagree it won't do anything negative. The car was sluggish as hell and stayed that way for about three more regular tankfulls (almost a month) before finally becoming more "normal", and the exhaust smelled funny (like turpentine or kerosene) most of that time as well.
I'll never do it again unless no choice, and even then use just enough to get down the road to another station with Super.

[nona.M]

Thanks for the input guys

Yeah I also ran 87 once when I first picked up the Z in Tucson and noticed it was sluggish, 7 years later and I haven't used 87 again nor plan on using it

[NolimitZ32]

D, I would venture to bet that the 87 you ran was low quality or even had began to separate (depends on age and environmental conditions). Under "driving miss daisy" operation 87 shouldn't have a detrimental affect on driveablity, that's not to say that performance wont be hurt, but the car will run and it wont ping. Now if you're trying to WOT, that's a different story.

[DCaff300ZX]

It was just really sluggish and would take far longer to get up to freeway speed- the freeway entrance from that town was REALLY short and normally I'd get to 60-ish at the end, barely up to speed and merging but after the 87 it barely made 50 and was coming on really slowly. Throughout the drive home it also wasn't willing to run at 80+ like normal and as most everyone else does along the very long open freeway stretch, I had to run the slow lane or be run off the road. I hit a station later and re-filled the tank with premo, but it only took about 1/4 tank and by the time I refilled fully was another two days. It ran crappy for about a month as I said, slowly though it came back to normal, mostly after I also did some fuel system maintenance- my first-ever work on the NA. I actually thought I'd toasted it up the way it was running, and I also recall that it lost it's first injector about 6 months later and the repairs were really on from there until it died a few years back.