Mixing fuels

[Sven59]

Thanks for everyones inputs!

[CanadianZL1#992]

When I switch to race gas I run my car down under 1/8 on my way to the track or drive around abit in the afternoon to run the car down till the fuel light comes on then pour in 2 cans of fuel. The plug in my handheld and download tune

[CanadianZL1#992]

Originally Posted by Sven59

Thanks for everyones inputs!

Hope you find something that works for you. My method is a bit of a pain but I picked up 65rwhp.

[Sven59]

Originally Posted by CanadianZL1#992

Hope you find something that works for you. My method is a bit of a pain but I picked up 65rwhp.

I will, just trying to figure out all the variables, it was so much easier in the old days!

[jon6.0]

It depends on your tuner if you have a low and high octane table. Some tuners copy and paste the high octane table to the low table.

[ZO6 Bryan]

Originally Posted by jon6.0

It depends on your tuner if you have a low and high octane table. Some tuners copy and paste the high octane table to the low table.

That's a good way to blow up a supercharged engine.

[ZO6 Bryan]

Originally Posted by CanadianZL1#992

I think with a custom tune the tables are set and will not adapt. I don't think a fuse pull does anything like it does to a stock tune.

Not true.

[CanadianZL1#992]

Originally Posted by ZO6 Bryan

Not true.

So with a custom tune how does a fuse pull change the fuel tables

[ZO6 Bryan]

Originally Posted by CanadianZL1#992

So with a custom tune how does a fuse pull change the fuel tables

Same as stock tune. The short answer is pulling the fuse resets everything. If your car has been having knock retard it will start using the low octane table. If it hasn't been experiencing a lot of knock retard pulling the fuse won't change squat. This goes for stock tune or custom tune. In all instances the PCM will return to the high octane table all by itself if you put better gas in the gas. It will take several miles though. And how fast it get's back to the high octane table depends on how far off it was before. If you use premium fuel all the time pulling the fuse is a complete waste of time.

[CanadianZL1#992]

Originally Posted by ZO6 Bryan

Same as stock tune. The short answer is pulling the fuse resets everything. If your car has been having knock retard it will start using the low octane table. If it hasn't been experiencing a lot of knock retard pulling the fuse won't change squat. This goes for stock tune or custom tune. In all instances the PCM will return to the high octane table all by itself if you put better gas in the gas. It will take several miles though. And how fast it get's back to the high octane table depends on how far off it was before. If you use premium fuel all the time pulling the fuse is a complete waste of time.

I do run premium fuel all the time but often wonder if what's coming out the nozzle is really premium. I've usually got quite a bit of race gas left in my tank when I switch my tune and fill up with pump gas so I feel pretty safe.

[Sven59]

So, stock I shouldn't have to do anything after adding torco but when I go back to 91 I will? Is that correct

[ZO6 Bryan]

Originally Posted by Sven59

So, stock I shouldn't have to do anything after adding torco but when I go back to 91 I will? Is that correct

Still shouldn't need to do anything. The car takes car of itself. All this fuse pull stuff is urban myth. Only time it would help is if someone filled your car with 87 or 89 octane. Pulling the fuse would speed up the recovery to the high octane table. What the car would do on it's own anyway.

[Sven59]

Thanks for the info!

[ZO6 Bryan]

Originally Posted by Sven59

Thanks for the info!

Actually I take that back. You said you wanted to put in higher octane(race fuel) and drive to the track. To make sure you get the most timing advance at the track pull the fuse. You don't want to drive around a lot wasting your expensive fuel waiting for it to return to the high octane table. So fill with race gas. Pull the fuses for a few minutes then go to the track.