Racing fuel w/185MM
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2005 Pontiac GTO 6.0 LS2 - Blue
Racing fuel w/185MM
Should I be safe using race fuel when I head back to the drag strip tomorrow on Friday? My dyno showed a 12.2 air to fuel ratio. That's a little on the lean side correct? With higher octane shouldn't that put me down towards a safer a/f ratio, and increase power output? I don't know much when it comes to A/F, but I know several people on this forum suggest around 10.5 or so...
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Should I be safe using race fuel when I head back to the drag strip tomorrow on Friday? My dyno showed a 12.2 air to fuel ratio. That's a little on the lean side correct? With higher octane shouldn't that put me down towards a safer a/f ratio, and increase power output? I don't know much when it comes to A/F, but I know several people on this forum suggest around 10.5 or so...
I'm not as keen as others on the A/F but I would assume that your ratio would stay the same whether you are on race gas or pump
since you aren't really adjusting anything by swapping fuel.As a side note I LOVE the smell of spent race gas
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What ever you decide definitely make sure that you are using the unleaded fuel.
I'm not as keen as others on the A/F but I would assume that your ratio would stay the same whether you are on race gas or pump since you aren't really adjusting anything by swapping fuel.
As a side note I LOVE the smell of spent race gas
I'm not as keen as others on the A/F but I would assume that your ratio would stay the same whether you are on race gas or pump
since you aren't really adjusting anything by swapping fuel.As a side note I LOVE the smell of spent race gas
+1, nothing like it, almost sweet smelling!!
One guy at Morrocco IN last year insisted that he was not running race gas and when I smelled the exhaust, it was like sitting in a Fannie Mae Candy factory. I said, yeah, sure.
Its distinctive for sure, even the unleaded stuff.
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03 g35 coupe...........02 c32 Sold
Your af will be the same. The knock sensors will probably notice the higher octane and slightly advance the timing a little. But you need a tune to really benefit from the race gas.
Race gas just allows for more timing before detonation and for your engine to run at higher compression..either via boost or high compression pistons.
I think robertamg said 12.5 was the afr that gave the most power. He wrote a thread about it some where. On the newer engines you can run slightly more lean. On older engines like a lot of iron block engines, they recommend you run like 10.5 to 11.5.
If your hitting 12.2 at 6200rpm thats fine.
Race gas just allows for more timing before detonation and for your engine to run at higher compression..either via boost or high compression pistons.
I think robertamg said 12.5 was the afr that gave the most power. He wrote a thread about it some where. On the newer engines you can run slightly more lean. On older engines like a lot of iron block engines, they recommend you run like 10.5 to 11.5.
If your hitting 12.2 at 6200rpm thats fine.
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Run that race fuel. Race fuel is safe*... Much better gas than you will ever find at the pump. Spike that thing with 100oct and let her rip.
Out here in AZ, it is recommended to spike your pump gas with some 100oct or 109oct. The gas out here is just that bad. The other day a EVO made 50WHP!!! just by adding 2 gallons of race fuel to the crappy gas we have out here.. Its really that bad
Out here in AZ, it is recommended to spike your pump gas with some 100oct or 109oct. The gas out here is just that bad. The other day a EVO made 50WHP!!! just by adding 2 gallons of race fuel to the crappy gas we have out here.. Its really that bad
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Just remember if you are running lean the higher octane is going to have a harder time detonating, detonation is what kills an engine. I say run the higher octane race fuel.
Most lay people believe it is more powerful, in reality as most on here would concur, it acctually means it is harder to ignite. that is why you have to run higher octane in a higher compression engine, because it won't ignite as easily, ie. under lean or high pressure, also known as compression ignition. Though the lean will still burn hotter which could in turn melt your pistons.
Most lay people believe it is more powerful, in reality as most on here would concur, it acctually means it is harder to ignite. that is why you have to run higher octane in a higher compression engine, because it won't ignite as easily, ie. under lean or high pressure, also known as compression ignition. Though the lean will still burn hotter which could in turn melt your pistons.
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2005 Pontiac GTO 6.0 LS2 - Blue
I was talking with a guy on youtube, and he said if you measure AFR at the exhaust tips the reading is usually .5-.7 leaner than the mixture really is, which is what I did at the dyno, so should be running 11.8 or so AFR. Wouldn't say that's a lean burn?
I'm in NM and tend to think the gas out here isn't so great either. Highest octane we can get is 91, and from what you're saying it's probably lower than the rating... In this case shouldn't 110 octane make a noticeable difference?
I do have the Eurocharged Stage 2 ECU tune...
Out here in AZ, it is recommended to spike your pump gas with some 100oct or 109oct. The gas out here is just that bad. The other day a EVO made 50WHP!!! just by adding 2 gallons of race fuel to the crappy gas we have out here.. Its really that bad
Completely agree with everyone (esp the race gas smell!!), get a tune first.
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2005 Pontiac GTO 6.0 LS2 - Blue
Just got back from the drag strip. Decided to give the higher octane fuel a try. Ended up using "C112" from VP racing 3 gallons mixed with 6 gallons of 91 premium pump petrol. The C112 cost $10 dollars a gallon. The results were interesting... The exhaust flame I shot shifting 2nd to 3rd on my fastest run was awesome!
There was a very noticable decrease of power throughout the low RPM range. Going off the line was completely different. Had to apply a lot more throttle to get off the line with good acceleration. However, after climbing RPM and boosting higher the acceleration was faster. Increase of nearly 6MPH crossing the line. On the cruise home the C32 started to act up with random increase/decrease of RPM during idle and a pulsating feel to the engine. Towards the end to the point of nearly stalling out. Stopped at gas station and pulled pending code for MAP. Topped off tank with 8 gallons of 91 premium and no issues after.
Custom intake / Head Wind - 14.040 @ 99MPH
Stock intake / Good Conditions - 14.202 @ 98MPH
Stock intake / Racing Fuel - 13.91 @ 103.5MPH
Da Calculation for fastest lap. 7848ft density altitude.
Stock and Mildly Modified Naturally Aspirated Engines
12.533 @ 113.915 MPH
Extensively Modified Naturally Aspirated Engines
12.818 @ 111.233 MPH
Extensively Modified Supercharged and Turbocharged Engines
13.309 @ 107.459 MPH
There was a very noticable decrease of power throughout the low RPM range. Going off the line was completely different. Had to apply a lot more throttle to get off the line with good acceleration. However, after climbing RPM and boosting higher the acceleration was faster. Increase of nearly 6MPH crossing the line. On the cruise home the C32 started to act up with random increase/decrease of RPM during idle and a pulsating feel to the engine. Towards the end to the point of nearly stalling out. Stopped at gas station and pulled pending code for MAP. Topped off tank with 8 gallons of 91 premium and no issues after.
Custom intake / Head Wind - 14.040 @ 99MPH
Stock intake / Good Conditions - 14.202 @ 98MPH
Stock intake / Racing Fuel - 13.91 @ 103.5MPH
Da Calculation for fastest lap. 7848ft density altitude.
Stock and Mildly Modified Naturally Aspirated Engines
12.533 @ 113.915 MPH
Extensively Modified Naturally Aspirated Engines
12.818 @ 111.233 MPH
Extensively Modified Supercharged and Turbocharged Engines
13.309 @ 107.459 MPH
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2005 Pontiac GTO 6.0 LS2 - Blue
as said...by temjin
don't bother with race gas if you don't have it tune for it. can't hurt, but you'll be just wasting it away.
don't bother with race gas if you don't have it tune for it. can't hurt, but you'll be just wasting it away.
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Those are about the same results the Pikes Peak Marathoners get up in the "thin" as they call it. Your DAs are ridiculously poor compared to us landlubbers near sea level. You ought to put your runs into the DA calculator for about 500 feet and see what they are??
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03 g35 coupe...........02 c32 Sold
well just keep in mind, the energy potential in 87 and race gas is the same. The only difference is there resistance to knock. The higher octane has a higher resistance to knock and vice versa.
Race gas can go through higher compression before detonation. So you can add more compression without have to worry about detontation.....more compression IE more boost or higher compression pistons. More compression usually equals more power.
I think your confusing race gas as more a power adder, like nitrous or something like that.
You need a tune to take advantage of the extra detonation resistance.
Race gas can go through higher compression before detonation. So you can add more compression without have to worry about detontation.....more compression IE more boost or higher compression pistons. More compression usually equals more power.
I think your confusing race gas as more a power adder, like nitrous or something like that.
You need a tune to take advantage of the extra detonation resistance.
Last edited by TemjinX2; Sep 1, 2010 at 05:24 AM.
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Your car with your mods should be at 12.8-12.9 according to my analysis of Dragtimes and other forum members. I'd say anything in the 12s should be where you'd be at sea level. Getting a C32 into the 12s is really NOT that hard. Assuming decent radials or DRs and good DAs, your mods should allow you to run all day long in the high 12s!! Problem is , altitude is killer on cars and runners. Trust me , been there done that!!
Last edited by Newzchspy; Sep 1, 2010 at 06:48 PM.
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You need a tune to take advantage of the extra detonation resistance.
Problem is , altitude is killer on cars and runners. Trust me , been there done that!!
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03 g35 coupe...........02 c32 Sold
You don't have a upgraded heat exhanger. I'm pretty sure heat soak is influencing your times more then the race gas. Even stock,..running the car hard 3 or 4 times, the car starts to have massive heat soak and starts losing power.
its your money...
You might as well just use e85, its cheaper and 110 oct.
its your money...
You might as well just use e85, its cheaper and 110 oct.
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W206 PHEV AMG
I see what you're saying however that doesn't add up. If that were true I should have had little to no difference after utilizing a mix of race fuel. There was a substantial difference in quarter mile time and MPH?
Very true, I believe that is why my intake makes 20whp/20wtq at my altitude. Looking at the design it seems way overkill, but it's able to move more volume of air to make up some for the lack of density.
Very true, I believe that is why my intake makes 20whp/20wtq at my altitude. Looking at the design it seems way overkill, but it's able to move more volume of air to make up some for the lack of density.
based on your mods if the numbers are corrected you should've hit those number easy every time without the 100oct.
as for drag racing numbers, for some cars you launch better you can get better trap as well as higher mph.
running higher oct...the ecu in these car is not going to magically adjust instantly to the oct rating it is receiving. octane rating is related to how much energy required to ignite the fuel. The knocking/stalling feeling you got was because of the higher octane you got wasn't ignited when it should causing a loss of power that feels like "almost stalling" out.
the only time high octane actually works is when cars have the changeable fuel mapping (mostly on the turbo cars i.e. Supras, EVOs, STis, B5 S4s, etc.) where they can press a button or two and change the mapping to that of the higher octane rating.
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2005 Pontiac GTO 6.0 LS2 - Blue
You don't have a upgraded heat exhanger. I'm pretty sure heat soak is influencing your times more then the race gas. Even stock,..running the car hard 3 or 4 times, the car starts to have massive heat soak and starts losing power.
You might as well just use e85, its cheaper and 110 oct.
were they consecutive runs? if not, how can you produce exactly the same condition and compare those numbers?
Stock intake / Good Conditions - 14.202 @ 98MPH
Stock intake / Racing Fuel - 13.91 @ 103.5MPH
Each time was a week apart. Go there on Friday for test and tune. Temperature and humidity were very close each time. DA is nearly 8000ft. Ran around 10 times each Friday, and was getting consistent results.
based on your mods if the numbers are corrected you should've hit those number easy every time without the 100oct.
as for drag racing numbers, for some cars you launch better you can get better trap as well as higher mph.
running higher oct...the ecu in these car is not going to magically adjust instantly to the oct rating it is receiving. octane rating is related to how much energy required to ignite the fuel. The knocking/stalling feeling you got was because of the higher octane you got wasn't ignited when it should causing a loss of power that feels like "almost stalling" out.
