Was wondering if race gas makes a huge difference on our cars? I know it serves a purpose on a turbo car, but does it do the same on a cobra. On most turbo cars, running race gas will allow them to run more boost. For example, a srt running 22-24psi, will now be able to run 30psi. It allows the engine to be a lot more boost friendly. Our cars arent turboed, so i assume that it wouldnt be as beneficial as a turbo car, but I may be wrong. Can anyone relate to this? Im sure a lot of you guys on here have tried race gas. What does it do and what can we expect from it? Thanks!!
Does Race Gas make a big difference?
- Thread starter chrisle7220
- Start date
Racing gas is a gasoline with a higher octane rating, usually 100-114. The higher the Octane rating, the more it resists detonation under pressure before it is actually detonated with a spark. The more boost you add into the engine, the higher the pressure, and the more apt the gasoline is to ignite prematurely (aka knocking, pinging, etc..).
When you start throwing in more and more oxygen particles (increasing the cylinder pressure), like what a supercharger, turbo, or even nitrous does, the easier it is to pre-ignite UNLESS you have a higher octane gas that will resist this pre-ignition. You can keep increasing the amount of oxygen (turning up the boost) into the cylinder as long as you keep adding more gasoline, and this will give you more power, with the higher octane giving you more protection from preignition, detonation, knocking, whatever you want to call it.
If I explained it wrong, someone chime in.
When you start throwing in more and more oxygen particles (increasing the cylinder pressure), like what a supercharger, turbo, or even nitrous does, the easier it is to pre-ignite UNLESS you have a higher octane gas that will resist this pre-ignition. You can keep increasing the amount of oxygen (turning up the boost) into the cylinder as long as you keep adding more gasoline, and this will give you more power, with the higher octane giving you more protection from preignition, detonation, knocking, whatever you want to call it.
If I explained it wrong, someone chime in.
dead on 03RedCobra!
Please correct me if I'm wrong, but to get the most benefit from race gas, you have to adjust your timing as well. IMO, everything else remaining the same, race gas will only be a small benefit over 93 octane with the same timing. Now if you are already pinging with 93, then race gas will help. If you have a chip or Predator, and you can bump your timing when you use race gas, then that's another animal. With a turbo and an adjustable wastegate, turning up the boost is easy. Having to change pullies to increase boost can be a PITA. If you're only running race gas ocassionally, then it would be worth it to go with a SCT 4 position chip or Diablo flip chip. I would also include a dyno tune with race gas and with just 93 octane as well. Just my 2 cents.
Only way I see a benefit is if you have a knock sensor and you are getting slight detonation. The ECU will retard timing as not to blow the pistons to shit. By adding the race gas the knock sensor will not send signals (detects no knock) to the ECU and you'll get more HP if the knock sensors was doing it's job before, through full timing.
Don't think it's any help to the 03-04 Cobra unless you up da boost or timing or both!
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If nothing else, it smells nice
thats for sure.:rockon: i can smell leaded race gas from miles away.
I ran at Quaker city dragway a few weeks ago, almost ran out of gas. The only thing they had at the track was 110 leaded so i put a few gallons in. Results were -1.5 mph and - 1 tenth. Same day, conditions, cool down between rounds. Not sure the reason but i made 3 more runs after the new fuel and all were the same.
most likely you lost because the car pulled timing to compensate for the higher octane,
It has always been my understanding for years that if you use leaded gas in a car that was made for unleaded gas that you will melt-down the catalytic converter core and the engine will eventually cease to run since the exhaust is in essence plugged up from the meltdown.
Any truth to that?
Any truth to that?
Yes there is truth to that. Do not run leaded gas in a car with cats. Also it can foul the 02 sensors as they are not compatible with leaded gas.
A reason you may have lost performance is the octane was too high after you added the race gas. If your computer is setup for 91 octane, 100 octane is too much. The power window needs to be within a few octane of the tune you are running. Usually the rule is 3 octane over the tune you are running is the most octane fuel you want. Anything over that and the performance starts to decrease. The reason is, the octane raises the temperature of the combustion of the fuel. If the tune(timing and fuel) is set to 91(as an example), the fuel will burn correctly on time with up to 94 octane. After that the fuel is burning slower than the tune is setup for. And the performance will start to degrade. The plus side here is that the higher octane won't hurt the motor as lower octance would. This instance is where people will start adding timing. To pull the cars tune back into line for the octane they are running.
The most power to be had is when the tune is set for 91 and you are running 91. Just using 91 as an example.
A reason you may have lost performance is the octane was too high after you added the race gas. If your computer is setup for 91 octane, 100 octane is too much. The power window needs to be within a few octane of the tune you are running. Usually the rule is 3 octane over the tune you are running is the most octane fuel you want. Anything over that and the performance starts to decrease. The reason is, the octane raises the temperature of the combustion of the fuel. If the tune(timing and fuel) is set to 91(as an example), the fuel will burn correctly on time with up to 94 octane. After that the fuel is burning slower than the tune is setup for. And the performance will start to degrade. The plus side here is that the higher octane won't hurt the motor as lower octance would. This instance is where people will start adding timing. To pull the cars tune back into line for the octane they are running.
The most power to be had is when the tune is set for 91 and you are running 91. Just using 91 as an example.
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