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Guys,

I was thinking about upgrading to a 20g. I was thinking about doing a street tune, 91 octane at about 17.5-18 PSI. My question is can I do a race tune on 100 octane at about 20PSI, or would I be safer just using regular 91 octane. The race tune would only be used 2 times a year when I go to the track. How much of a gain can I expect to see from 100 octane versus 91? If you guys have any other suggestions please post them!

Joe
 

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Depending on the tuner I would expect about 20-30hp more and maybe 50 ft/lbs of torque. It depends how the tuner goes about the map by raising boost, more timing, and leaner AFR's. The tuner can also go about using less timing and less fuel or more timing more fuel. The tune should be safe if you are only running it at the track (well if you have a good tuner).
 

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yep that is the nice thing about the EM we are using. You can switch between real time maps on the fly and not cause the ECU any harm. There is no reason you cant have a 91 map and a race gas map loaded and waiting to be switched for the track days....

The difference in my maps are 93 map -- 418 Whp
C16 map -- 524 Whp
 

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^Damn you put down 524whp with the 30R??.. that's nuts.. You have a graph of that by any chance overlayed on your pump gas map? Would love to see that..
 

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Difference between 91 and 100 octane will be a big one and you should be able to run closer to 23 or 24psi I would think.
 

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I'm not running the Perrin 30r, however, I can give you an idea as to the difference. This is an old graph. the 360 whp is a very consevative 10 to 1 afr tune at 18 lbs... The 450 whp is with a mild 100 octane tune. AFR's at 11 to 1 at 23 lbs of boost.... I'm running the APS DR 65r...... Hope this gives you an idea...:)
 

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^^ yeah esentially the octane moves the lines up on the graph.....sweeet :tup:
 

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On a VF39 you can expect 30hp. I would personally go with meth injection and a tune. Same gains and you can run it 24/7 and only kicks in when you give it the gas..
 

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^^ +1 on the Meth.... If I had to do it all over again... Bigger turbos arent always better... Meth is a great way to gain HP....:tup:
 
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