I have a supercharged sled with a head shim. How much boost is safe to run on pump fuel? I'm currently running 6lbs with 87 octane and have not experienced any detonation at all. If I were to bump the boost to 10 could I still run safely with 91 octane? If I were to do an ECU reflash as well would that take too much of the HP away to be worth it? Between the timing and the shim could I get away with lower octane requirements?
Octane requirements with head shim and boost
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mpi xtx
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I wouldn't even be running 87 with you current setup.
I ran 13psi with low comp pistons on 91 pump gas without issues
I ran 13psi with low comp pistons on 91 pump gas without issues
PowderFalcon
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You can run 91 with shim and studs (may as well do studs while head is off) on 10 lbs of boost. That is what I run in my sled.
I would be running 91 with your current setup if i were you, not worth the chance of a $5000 motor.
Also, please add your location on your profile! Cheers!
I would be running 91 with your current setup if i were you, not worth the chance of a $5000 motor.
Also, please add your location on your profile! Cheers!
rat4020
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I put the ARP studs and head shim on my Apex and its suposed to be good for 10-12lbs with 92 oct. But I dont trust pump 92 so I mix it 3.5 gal 92 to 1.5 gal of 110 Then even if I get 87 my octaine is still around 102 and safe & smellin great
I suppose you guys that are mixing fuel never really ride far from home. I can get away with that at the beginning of the day but my second fill up is generally 100 miles from where I'm staying so its simply not an option.
rat4020
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Filling up at a gas station is not an option for me LOL there aint no fuel stops where I ride. Just lots of sand ,my fuel comes from a 50 gal tank in the inclosed trailer
When I turn up the boost I ride with 5 gal of race fuel which gets me 2 additional fill ups if I am getting 92 pump gas so 3 tanks a day or about 250 miles. After that I head home and do it all over again
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Where do you put 5 extra gallons?
In the large rear tunnel bag
a 2.5 gal plastic tank and then 6 large fuel cell bottles depending on how far I am planning on riding or I can always flip the switch to reduce boost and lower my octane requirements.
a 2.5 gal plastic tank and then 6 large fuel cell bottles depending on how far I am planning on riding or I can always flip the switch to reduce boost and lower my octane requirements.
