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Race fuel ?

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What's the highest octain fule u can use in a stock boss 302 or stock laguna seca ? Is 103 safe ? Also would it give it any more hp !?!
 

steveespo

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Any unleaded fuel above 91 octane is safe, but depending on the tune, and ambient temperature too much octane may hurt power a little. I have my car tuned to use 93 Octane, when at track I mix in 25% 100 Octane Sunoco 260GT unleaded to give a boost up to 95 just for a safety margin at high RPM. You can get tunes that add more timing and lean it out a little that would call for the higher 100-103 Octane. Unless you are doing that or running super or turbo charger don't waste your money. At $10 a gallon and 6 mpg on track it gets expensive fast. My thought is the stock Ford strategy stops adding timing at a level where 93 Octane is the safe zone, Track Key does do timing increase on the bottom end to boost torque but even that is supposed to be safe at 91 Octane. If any others have more in depth info please chime in.
Steve
 

PeteInCT

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steveespo said:
Any leaded fuel above 91 octane is safe, but depending on the tune, and ambient temperature too much octane may hurt power a little. I have my car tuned to use 93 Octane, when at track I mix in 25% 100 Octane Sunoco 260GT unleaded to give a boost up to 95 just for a safety margin at high RPM. You can get tunes that add more timing and lean it out a little that would call for the higher 100-103 Octane. Unless you are doing that or running super or turbo charger don't waste your money. At $10 a gallon and 6 mpg on track it gets expensive fast. My thought is the stock Ford strategy stops adding timing at a level where 93 Octane is the safe zone, Track Key does do timing increase on the bottom end to boost torque but even that is supposed to be safe at 91 Octane. If any others have more in depth info please chime in.
Steve

I think you mean unleaded...

If you have a stock tune you won't get much of anything more if you run over 93 octane. as far as I can tell. I've heard the tune adjusts to octanes up to 100, but again I've tried it and there is no "seat of the pants" difference to me.
 

steveespo

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Pete
Thanks I fixed it too. I would like Mark Wilson to chime in because I really don't think Ford would program the car to adjust timing beyond what is readily available(93). Track key maybe, with a custom tune you can force parameters pretty much up to destruction, including shutting off the knock sensors.

Dyno runs with different fuels may show what really happens, maybe Colecree or Seca will give it a try and post results?
Steve
 

ArizonaBOSS

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I dunno but running 100 octane at Chuckwalla seemed to clear up the P30x misfire codes I was getting running 91 with TK; I might just run 100 from now on at the track.
 
seca954 said:
I'd like to hear opinions on this. I am under the impression that the computer learns how to make more power when octane is added.
I don't think it makes more power but it should pull timing less often. I've used 100 at the track and didn't notice any difference and still threw codes. My dealer contacted Ford about my codes. Ford wanted to know if I was using race gas and recommended that I NOT use the 100 which made no sense to me. It was originally reported that TK would adjust for higher octane but I've never seen that confirmed.
 

steveespo

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NFSBOSS said:
I don't think it makes more power but it should pull timing less often. I've used 100 at the track and didn't notice any difference and still threw codes. My dealer contacted Ford about my codes. Ford wanted to know if I was using race gas and recommended that I NOT use the 100 which made no sense to me. It was originally reported that TK would adjust for higher octane but I've never seen that confirmed.
Ford PR said a lot of cool things about track key- CARB made them change their mind :'( the concept is awesome but truly letting the engines perform to their max requires removing emissions equipment and programming that makes the cars non compliant and also endangers the catalytic converters which have to be warrantied for 8 years/80000 miles per Federal Laws. Ford doesn't want to have replace parts after sanctioning their damage with an all out tune. That's also why "racing events" void warranties, theoretically the cars can be operated at 7450 rpm continuously and still be warrantied, of course that is on public roads, so you have to drive around town in 1st gear and on the highway in 2nd to do so.

There is no free lunch, you gotta pay to play and horsepower is expensive.
Steve
 
No way to dyno for me so I Gus I have to go to the strip with 94 octain run about 6 or 7 passes then put 4 or5 gallons of VP 103 race fule ... Well c what happends
 
Colecree said:
No way to dyno for me so I Gus I have to go to the strip with 94 octain run about 6 or 7 passes then put 4 or5 gallons of VP 103 race fule ... Well c what happends

I'd love to find a track where anyone had the luxery of making 6-7 passes for a baseline. Please post your results.
 
Oh not track drag strip wish I could find a track close the closest track u need a membership ! Mont tremblant n it's probly expensive ! But the drag strip should open soon still some snow
 
Keavdog said:
Higher octane has the resistance to detonation. Unless you are advancing your timing there's no perc to paying more.

I was under the impression that the computer would learn that it could advance timing with high octane. I agree that simply pouring high octane and making no changes won't make more power. The question is, is the computer making any changes?In the old days we could mess with the distributor and make more power.
 
Here is a quote I received from the Ford engineer(Jeff Seaman) that programmed track key.

"Using the TracKey calibration on a stock setup with 93 Octane would be an excellent idea. The knock control is programmed to run on anything (unleaded) up to 100 Octane."
 

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