Home Brew Octane
 

If your car is tuned for 93 octane and you travel out of state you need to find out if 93 octane is available, or use a fuel additive to adjust your octane level or risk damage to your engine.

I knew little about this subject so I did some research on fuel additives. What I learned was suppressing. Most fuel additives will only raise your octane a few tenths. Far short of what you really need. You need to concern yourself if you travel out of state. Know if you can get the right octane fuel or which booster you need and how much.

I found an interesting site that has some home brews to boost octane. This may not solve your problem when traveling out of state but this website is worth the read.

Check it out.
http://www.gnttype.org/techarea/misc/octanebooster.html

TORCO accelerator FTW! Its not off the shelf garbage, its concentrated race fuel.

8oz to 10 gals of 91 octane and you got 93!

16 0z to 10 gals of 91 and your at 95

3 gallons of E85 to 13 gallons of 91 should put you just over 93 octane....

If you put E85 in first and drive to the gas pump it will pull the concentrated mixture into the lines and possibly throw a lean code..... Just make sure to add E85 last and wait a couple minutes before driving so it has time to mix.

You can run up to 30% E85 and not fear a code, it'll skew your LTFT's around 10% positive and is 94.5 octane.(E10 91 and E85 mixed 3:1) Positive fuel trims are carried over into the PE, just drive 5 miles or so until it adjusts before whoopin' on it.

I.E. 12 gals of E10 + 4 gals of E85 ~= 29% E

http://www.intercepteft.com/calc.html

True, what's the max gallons of E-85 you've run these days????

I ran up to 60% E on the stock fuel system. Tuned for it though of course. 2:1 E85 and E10 93 is 60% E. Fuel mileage dropped to 17 though on my cruising. E47 I maintain 19 mpg and it's 99 octane. Injector duty cycle peaked at 80% in 50* weather in a hard pull. Seems to be the sweet spot as it was on my Turbo Cobalt LNF.

I make my own beer. Does that count ? lol The neighbors love me because I always have a brew on tap

The trouble with the ethanol % though is... '10s and '11s were designed for 10%. In '12 they made some changes to the Camaro, and now good up to 15%. Get above those percents they validated them to and who knows what the long term affects are. Probably not any problems right away, but anything that the fuel touches from the gas cap to the headgaskets is a guess if there will or won't be any problems down the road from running too high an ethanol content. A friend of mine is a powertrain engineer and he has told me several times, they make quite a few changes before calling it validated for E85. If it were simple, they would just E85 everything in the calibration to get all the great alternative fuel credits with Uncle Sam.

In the camaro I run E40 and it works perfectly..... just saying.... No check engine lights.... validated fuel trim to be at 9 to 11 in torque

Now in my old 02 ford escape I run E25.... Tried E40 and it took a few tanks, but It got really cold and wet and then I got a lean code on 2nd oxygen sensor... then again it has exhaust leaks too LOL

If your fuel trims are -3 to -4 on E10, what you say makes sense. E40 would require around 13% more fuel than E10.

Once I get the TVS done I'm going to see if I can run E47 again. Prob need a BAP to pull it off.

My trims were 0 or +1 or +2 on E10..... The point of fuel trims were to makeup for vacuum leaks that develop over the life of the vehicle and later on the blended ethanol. Oh and for fuel economy and air quality (not dumping excess raw fuel out tail pipe)

Essentially no tune is needed if your vehicle doesn't have vacuum leaks or very much of a vacuum leak.

The other point to that is that the additional octane is not needed beyond 94 octane (~E40 blend). I believe this largely is because of compression ratio and again lack of tune but mostly a higher compression ratio would take advantage of the higher ocatane fuel.

Without a tune it actually hurts performance, I'm guessing with a clean drop in K&N air filter plus E-40 I've gained an additional 20 to 40 horse power/torque. More than likely it's 40 engine horse.

Car pulls harder and starts to fish tail because of excess power with moderate acceleration even on perfect ashfault.

That being said, I'd love to see what a naturally aspirated 454, direct injected engine could do at a 13.5:1 or 14:1 compression ratios on E85 :)

Ahhhh... Engineering, part of the job is to be cautious and run through the process. What he's saying is likely true.... but the industry largely changed the materials after 2000 to accommodate for ethanol..... maybe not 85% but surely blends beyond 10%.

A little dab will do you!!!! :thumbsup: