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Discussion Starter · #1 ·
First time I'd run into this problem, but I was on a roadtrip last week and couldn't find anything but 87 octane gas along one long stretch of highway. I was already sucking fumes, so I had to grab 5 gallons of regular and hope the next town had 90+. I did add 2 cans of gas treatment and took it easy until I could find premium.

My question is, just how critical is it to run high octane in a slightly boosted (TRD SC) engine? Because if it is that big a deal, I probably should carry a couple of bottles of octane booster just in case I run into this again.

Thanks,
 

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I'm certain the knock sensors go a very long way in preventing engine damage as well as taking it easy on the throttle. You were smart to get only 5 gallons of 87 to blend with the premium you had remaining in the tank. It would be prudent to have a can or 2 of octane booster available just for these types of situations.

DEWFPO
 

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Discussion Starter · #4 ·
Slightly boosted? do tell!

Nothing to tell, I just wrote that poorly. What I meant was that I'm running the lower boost of the 2 SC options out there for the FJ (i.e., TRD versus URD).
 

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In your case, I would keep a couple of bottles handy.. Ron

First time I'd run into this problem, but I was on a roadtrip last week and couldn't find anything but 87 octane gas along one long stretch of highway. I was already sucking fumes, so I had to grab 5 gallons of regular and hope the next town had 90+. I did add 2 cans of gas treatment and took it easy until I could find premium.

My question is, just how critical is it to run high octane in a slightly boosted (TRD SC) engine? Because if it is that big a deal, I probably should carry a couple of bottles of octane booster just in case I run into this again.

Thanks,
 

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Octane booster does nothing. When it says that it raises the octane 1, 2, or even 3 points, that means it goes from 87.0 to 87.1, 87.2, etc.

Carry extra fuel on long trips. Or Toluene(sp?).

You can run lower octane, temporarily, with a S/C. Just stay out of boost. I know, it's hard.
 

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Discussion Starter · #8 ·
A knock sensor can only do so much to retard the timing to prevent knock.

IMHO, just dont lay into the throttle much which adds boost. The boost starts to come in after 2000 RPM???

Low RPMs and also don't bog it down is what I concentrated on. I know most engines seem to ping worse when really bogged down and that's what I wanted to stay away from.

I just mainly wondered if the knock sensors would fully compensate for 87 fuel, and if it was something I even needed to worry about if it were to happen again.
 

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BobKid, Get a Boost gauge and you can easily see when the SC is kicking in. You can also save gas if you wish too. :bigthumb:

Here's a few shots of mine. This is a Taco TRD boost gauge for the Supercharger. It has a nice sweep. Terry
 

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Hey,

You could always just put in a second gas tank like the one from MAF and keep it filled with 91 octane fuel. I can go between 650 to 750 miles between fill-ups depending how heavy my foot is.
 
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