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Hey guys, I usually run 4-5 gallons of VP 104 unleaded at the track, mixed with about 1 gallon of 93 pump gas (leftover from the drive there).

I was thinking about a few gallons of 116 leaded next time, since it's so friggin' hot this time of year. I was just wondering if it would instantly kill my oxygen sensor, or would it take several tank fulls to kill it. I only go to the track a few times per year...it's not like I'd be running leaded gas all the time. Would a few gallons here or there be really bad for the car?
 

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2-3 tanks of leaded gas and the o2 sencor is gone. I've ran about three tanks this summer and I think my O2 is gone.
The last time a ran leaded race gas my Greddy A/F gauge didn't work fot about a week.
 
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interesting....I have used 3 or 4 tank fulls this year and no problems. I know plenty of guys that have run 100+ gallons of it(over time of course) and no harm to the Z's O2's......weird.

Originally posted by Lue:
<STRONG>2-3 tanks of leaded gas and the o2 sencor is gone. I've ran about three tanks this summer and I think my O2 is gone.
The last time a ran leaded race gas my Greddy A/F gauge didn't work fot about a week.</STRONG>
 
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What do you do about your catalytic converter?

All that Pb will eventually bind up your cat and render it useless. You could still probably pass emissions in the 49, but I'm dubious about Cali....
 

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I would be surprised if you needed that much octane.

It may slow you down since it burns so slowly, the ECU probably doesn't allow enough ignition advance to make use of the octane number.

Plus it's not great for the O2's, as others have said.
 

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Originally posted by Lue:
<STRONG>2-3 tanks of leaded gas and the o2 sencor is gone. I've ran about three tanks this summer and I think my O2 is gone.
The last time a ran leaded race gas my Greddy A/F gauge didn't work fot about a week.</STRONG>
I have been running leaded race gas at the track for over 3 years with no problem at all. O2 sensors are fine and I probably have run at least 100 tanks of race gas over the years.

Let me add a word of caution on mixing race gas with pump gas... This does not result in an octane level as high as you might think. The theory that mixing equal parts race gas and pump gas will give you an octane level in the middle of the two is incorrect. Even a couple gallons of pump gas mixed with many gallons of race gas will result in an octane level only slightly better than the pump gas. If you are running boost levels over 26 psi, run straight race gas, do not mix! I have blown up two motors this way and learned some very expensive lessons.
 

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Originally posted by Lagtime:
<STRONG>I would be surprised if you needed that much octane.

It may slow you down since it burns so slowly, the ECU probably doesn't allow enough ignition advance to make use of the octane number.

Plus it's not great for the O2's, as others have said.</STRONG>
Chip hit it pretty much on the head. 110 octane is about the highest our ignition systems can burn properly. I have talked to a guy locally (Marko) about this and he experimented with 104, 110, etc, and he ran the best traps/times with 110. He is on stock ignition.

If you are running stock twins, 104 is more than enough I have found to run some great trap speeds.

-m

[ July 17, 2001: Message edited by: Marcus Frost ]
 
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