Mcxpress 270 nytro headshim

[NYTRO-270]

What would cause the headshim to fail?? Talked to a few people and they said at 17lbs you need to run 1/2 prem and half c12? Is this just under a certain elevation? Also Im going to turn the boost down to 14lbs. Is anyone else having headshim issues with the 270 kit?

 

[deepbreather]

too much boost for the fuel you are running, change it out before you warp the head and or block.

 

[NYTRO-270]

too much boost for the fuel you are running, change it out before you warp the head and or block.

ok thanks but whats your recommendation???

 

[deeker]

Nope my 270 runs great

 

[NYTRO-270]

My headshim did blow and filled the motor with antifreeze would you think i bent the head or case in order for the shim to fail?? Where are you running your 270 at for elevation ?? I am always over 4000 ft I would say. I take it your running 17lbs boost with premium fuel also??

 

[Washy]

You have to be at 7000 feet and over to run 17 psi on Premium. Anything lower and you will blow you head gasket out, or worse throw a rod through the block. I hae run 17 psi on premium before at that elevation but I now mix in some av gas to be safe.

 

[NYTRO-270]

You have to be at 7000 feet and over to run 17 psi on Premium. Anything lower and you will blow you head gasket out, or worse throw a rod through the block. I hae run 17 psi on premium before at that elevation but I now mix in some av gas to be safe.

I am picking up a drum of c12 and going 50/50 mix hope it works, going to try this weekend.

 

[DooTraxx]

These are supposed to be designed to run 16 lbs at sea level on pump premium. Then the boost should increase with elevation. Is this not what guys are seeing?

 

[Washy]

I would not run 16 psi at sealevel on premium regardless if they say to or not. I was told that by eric that it is safe to run 15.7 at sealevel also but I would stick to 13 or 14 at sealevel and 17 psi at elevation on pump premium. You get alittle crappy premium and kiss your motor goodbye at 16 psi at sealevel. You should be fine but......