What is the difference in race gases.. e85, 100oct, etc.. Which type of race gas is the best for power, and where can it be found?? Also, if I am tuned for one type of race gas, is it going to throw off the car if I put in a different type?

 

C16 will let you run the most timing and is best at quelling detonation. If you are tuned for that and run a lower octane fuel, your car will be more prone to knock.

 

E85 has 85% ethanol, 15% 87 octane.

E98 has 98% ethanol, 2% 87 octane.

C16 is 117 LEADED octane

Q16 is 117 LEADED octane with a little bit of oxygen in it

100 octane is usually non leaded.




The higher the octane, the more boost and timing you can run without detonation. Boost and timing = power

 

if Im tuned for 93 what could I expect from putting 100 octane in if I run all the 93 out (no new tune just a switch from 93 to 100)? and is 110 leaded or unleaded?

 

you aren't necessarily going to benefit from 100 octane if you aren't tuned for it because the car can't take advantage of it. And the only way to know if its unleaded or not is to check, because there is 110 leaded and 110 unleaded.

 

E85 is not 87 octane but closer to 105 and isn't a race gas but an alternative fuel.

 

Possibly reduced power and higher EGT's. It burns at a slower speed than pump and will make peak pressure later which can cause the flame front to chase the piston down the bore. This overheats cylinder walls and will reduce performance.

I originally said "knock" which is not correct as knock is a result of detonation, the reason I said knock is because a prior attempt at running 108without additional timing caused my car to flash the knock light. I didnt know that my laptop battery was dead and had grabbed a couple of gallons of 108 at the track, and had no way to tune it.

 

He is not referring to the overall octane rating, he is reffering to the octane level of the gasoline (15%) mixed with the ethanol (85%), which is in fact 87 octane

 

vp import is the best fuel available 120+ octane
serious $$$$$

 

Oops, I thought he meant overall.

 

the 100oct debate. some miss leading info here.

every simple.

if the car is tuned on 93 and has a little knock putting in 100 will most likely cure the know. ''depending why it is knocking''

putting 100oct in a 93 tuned car with no knock will sometimes hurt hp. but most of the time will do nothing at all.

now the reason most put 100oct in there 93 tuned cars is because they turn the boost up 4 too 6psi and run the car. this is normally safe on the 93 tuned car. but it must be done with a an empty tank and then fill it up with 100oct.

there is much more details that need to be said but im just to damn lazy right now. but this is a fast explanation.

 

You should be able to find race gas at the race track; especially drag race tracks

 

To the OP: MS109 unleaded gas is probably your best bet. C16 might make a little bit more power, but, as has been mentioned, it is leaded. Leaded gas will destroy your factory O2 sensors rather quickly. I would suggest doing some searching on the forums in regards to tuning for different octane levels. As a simple rule of thumb, if you are tuned for x octane, then you can usually run x + 5 octane without ill effect. However, once you start jumping from, say 93 Octane to 109 Octane, you will probably lose power. This is why you'll see me fill up with 93 octane and then add a gallon or two of 100 octane unleaded ... gives me a small extra safety margin.

E85 is an interesting option, but your fuel system needs to be upgraded to take advantage of it.

l8r)

 

Anyone here juice up with a little xylene or toluene after filling up?

On another note, I was running out of denatured alcohol at the track 2 weeks ago and had to dilute to a mix of 50/50 alky and distilled water. It felt like I lost quite a bit of power.

 

Your tune will play a big role in the outcome..... if you are on the stock maps and crank up the boost you'll end up in a load level with negative timing and performance will suck *****.

I run a mix of 93 and 110 leaded. With the 100 blend I spike an additional 4psi and 4* of timing from 200-320 load. Most of my lowend gains come from the boost and most of my top end gains come from the timing (car doesn't hold boost that well).

I doubt you really need anything greater than 100 octane on the stock turbo unless you are attempting to turn it into a mini flame thrower by running 30psi.

I've had **** poor luck with unleaded race gas. It tends to age quickly and doesn't provide the knock supression of the leaded stuff. I know everyone says leaded fuel will kill O2 sensors but I've run hundreds of gallons of 110 through my DSMs and EVOs and have never had to replace a sensor. I think the trick is to not run straight leaded fuel and run unleaded when you aren't racing. I tend to go for a week or so on pump then run 10-20 gallons of leaded through the car at a lapping day or special "meeting of the minds" on some back road. Cats on the other hand do not stand up well to race gas.... then again WTF do you still have a cat on your car for?

Around here we can purchase 110 leaded turbo blue at the pump. Up until last week it was $5.45/gallon. This week the price jumped to $6.35/gallon. Still not to crazy. Splitting it with 93 gives you 100+ octane for only a dollar more a gallon.

I recommend buying it at a pump because race gas doesn't age well. If you buy it from a low volume seller it may be old and not as potent.