Octane boosters

[Ziegelsteinfaust]

Do any octane boosters work enough to get up from california piss water 91 to a decent 93. I have tried all brands of gas to only slight differences.

I finally finished tuning my engine as best I could and have talked to a few experts. My combined mechanical/dynamic compression is to high.

So I want to try better octane booster then parts store stuff which helps, but I do not know a good brand. Or if any truly work. Besides around the margins.

If I can hold out long enough to get things in order I want a LS variant. Or if no temp solutions will work I will do a LT1 350 as it will be plug, and play. Plus I know carbs where fuel injection can throw me a loop I would get stuck on.

This is my only vehicle so I have to play it as safe as I can.

[burnin oil]

Do you have E85 around? When I would get a bad tank of fuel I would spike it with E85. It has a higher octane rating but less BTUs per gallon.

[Getter-Done]

Have you tried Amsoil?

Link: https://www.amsoil.com/p/dominator-octane-boost-aob/

[Ziegelsteinfaust]

Originally Posted by burnin oil

Do you have E85 around? When I would get a bad tank of fuel I would spike it with E85. It has a higher octane rating but less BTUs per gallon.

Not in large enough quantities. Of the places I go both of the stations in my area are out of the way, and would be annoying to go to.

I have dreamed of building a E85 engine, but not for a DD where I live. Plus if I went to visit family I would have to bring enough fuel to finish the return trip.

If worse comes to worse. I rather build a throw away 350. It would be emotionally easier to deal with. As at 430 am I need gas I can stop anywhere vs a special trip in the wrong direction to work.

I have access to a 283 that needs a regasket, and manifold. That I could make work if need be.

[Ziegelsteinfaust]

Originally Posted by Getter-Done

Have you tried Amsoil?

Link: https://www.amsoil.com/p/dominator-octane-boost-aob/

No I have not. I got a line on some stuff that supposedly works well, and is available locally to try.

But I will look to see if I can get a bottle to try first.

[Greasey Harley]

Just FYI "Raises octane level one point" means it raises it from 91 to 91.1, not 92.
Maybe you already knew that, but I thought it was worth mentioning.
VP Octane booster will boost up to 70 points (advertised)
You can also cut cheap gas with 101 aviation fuel, that works pretty good.

[Ziegelsteinfaust]

Originally Posted by Greasey Harley

Just FYI "Raises octane level one point" means it raises it from 91 to 91.1, not 92.
Maybe you already knew that, but I thought it was worth mentioning.
VP Octane booster will boost up to 70 points (advertised)
You can also cut cheap gas with 101 aviation fuel, that works pretty good.

I did my research and that is a trick I learned about. Since I never built a engine to use it as I always played it safe enough with my choices.

Some stuff I got will give me a several point increase. So I have to do the math when I get the formulas to see how I want to approach it. Or atleast people on the internet claim it is good, and I could have it delivered.

I forgot about AV gas, and that is a option. Since I pass by a air port often enough. Plus with a lower compression motor already found. I can play with that for a month or two while I get ready for a swap out.

[sweetk30]

Av gas has lead in it . So watch cats and o2 sensors .

Plug there not suppose to sell to non airplane . . Faa rules atleast in my area .

[MySons68C20]

Originally Posted by Greasey Harley

Just FYI "Raises octane level one point" means it raises it from 91 to 91.1, not 92.
Maybe you already knew that, but I thought it was worth mentioning.
VP Octane booster will boost up to 70 points (advertised)
You can also cut cheap gas with 101 aviation fuel, that works pretty good.

I agree with GH on this. The VP stuff has a good rep. The last time I bought 110
octane race fuel it was over $10.00 a gallon and not available everywhere.

[bnorth]

Back in my high hp turbo Honda days we used to mix toluene in with pump for a little extra protection. This stuff: http://race-gas.com/ is supposed to work well as well.

[mattfranklin]

More than you'd ever care to learn about octane improving blending components:
https://www.nrel.gov/docs/fy00osti/28193.pdf

Another fun option would be water injection.
I haven't seen it promoted much lately. but theoretically should be helpful.
EDIT: It looks like water injection systems have come a long way from when they just used to use a windshield washer pump:
https://www.summitracing.com/search/...ection-systems


Honda & MIT had a pretty cool SAE paper a few years ago. They'd get regulsr E10 gas and then split the base gasoline and ethanol with a special membrane. Then during high manifold pressure conditions, you'd have extra ethanol to inject. Not commercialized anywhere as far as I know.

['68OrangeSunshine]

You can't get it anymore, but TetraEthylLead used to come in a 1 Qt bottle for a 20 gallon fuel tank. My '68 Stepside ran like it was the Sixties all over again.