Octane booster

[SoCal250]

We don't even have a 93 button here. Our crappy swill tops out at 91 (R+M/2). And it still costs $5/gal right now

[m in sc]

yeah, cali, fla and texas are 'locale non grata' for me to live. ya'll can keep all that. 

[Brad-Man]

I can understand Cali, but FL & TX?

[m in sc]

ive been to fla enough to not want to be there, and texas is just weird

[The Red Scourge]

ive been to fla enough to not want to be there, and texas is just weird

I lived in Florida for 5-1/2 years.  It was about 5-1/2 years too long.

[Jspooner]

I also just run straight pump gas in my TZ. I just buy the highest octane that is available wherever I happen to be. FWIW, with new rings my motor has 160 psi readings and the head still has the original design combustion chambers. I would not use octane booster either.

[teazer]

What it comes down to is whether there are signs of detonation.  If not, pump gas is sufficient.  I ran the phat trakka at 165-170psi on 91/93 octane with no problems.  In a TZ or TD race motor that gets heat soaked at full power, 100 octane was more than enough to keep it safe.

You can mix two lots of gas with different octane ratings to get something between but it's not a straight average.  Octane rating is simply a measure of resistance to detonation. Higher octane does not equate to more power until the motor is at the limit of detonation.  On a street motor that's rare unless timing or jetting are way off. And if they are, fix it...

[m in sc]

What it comes down to is whether there are signs of detonation.  If not, pump gas is sufficient.  I ran the phat trakka at 165-170psi on 91/93 octane with no problems.  In a TZ or TD race motor that gets heat soaked at full power, 100 octane was more than enough to keep it safe.

You can mix two lots of gas with different octane ratings to get something between but it's not a straight average.  Octane rating is simply a measure of resistance to detonation. Higher octane does not equate to more power until the motor is at the limit of detonation.  On a street motor that's rare unless timing or jetting are way off. And if they are, fix it...

exactly. ^ best explanation yet.

[IR8D8R]

The only thing I ever used was toluene 10%. The commercial stuff is useless. Toluene is the most common major additive in most racing fuel. You can smell it. F1 spec fuel has been as high as 84% toluene which by itself has a MON of 121 octane.

I have no idea how a 2-stroke reacts to it. My cars always ran fine and stopped audibly pinging. I think I would want EGT sensors in place to experiment.

There is quite a bit of data online about the use of toluene as an additive in gasoline. Most of it is positive. It's not $3.99 a gallon anymore and not on the shelf at ACE hardware and Home Depot like it used to be.

This article is interesting:
https://nyet.org/cars/info/toluene.html

The author of the article made an error in calculation where he projects the expected octane numbers. According to an SAE whitepaper, the effect of toluene addition is not linear by %. The author assumed that it was.

IR8D8R