je pistons vs head shim

[gunnerthesnowman]

friend of mine runs propane, cracked the head and cracked the piston @ 26 lbs, rods survived

If i remember right , you have to boost twice as much on propane to make the same power , so many guys are stuck on high boost # , it all about the efficiency of the set up and how well its tuned .

 

[XtremeSpeedShop]

We have one whole season on one motor with Je pistons, carrillo rods, arp head studs/bolts @25lbs no problems at 4-6k feet. We also ran C-16 in it though, good fuel is key and with 30k into a sled a few bucks a gallon goes a long way. Going to Oring one block this season. We have a 600 trx honda, 140hp turbo raptor and a few other bikes oring with zero problems, infact it has been the only way to solve head gasket problems on some motors. We will also have some low compression Cp piston ready to go from Impulse here soon.

 

[zebiraross]

If i remember right , you have to boost twice as much on propane to make the same power , so many guys are stuck on high boost # , it all about the efficiency of the set up and how well its tuned .

Agreed.

 

[Tuesday]

If i remember right , you have to boost twice as much on propane to make the same power , so many guys are stuck on high boost # , it all about the efficiency of the set up and how well its tuned .

Yes but the fill up cost on propane vs race fuel is way cheaper.

 

[Wheel House Motorsports]

If i remember right , you have to boost twice as much on propane to make the same power , so many guys are stuck on high boost # , it all about the efficiency of the set up and how well its tuned .

just to clarify some things on here, just some propane factoids to clear the mist.

propane has 74% of the energy of gasoline per volume, BUT, with its very high octane(and unique burn characteristics) very comperable amounts of power are able to be made via timing and motor setup to take advantage of said fuel. propane systems may make slightly less per pound, but safely being able to have a large margin of error on the detonation front will save you when it comes to keeping your motor together.

as far as why it cracked at 26#.... thats a LOT of boost and increased cylinder pressure compared to stock. either which way, a shim should be more then good as long as your tuned in and not on the ragged edge of deto.. if your pushing components to the limits.. good tuning and fuel is key.

 

[HANDSOME]

I was thinking more like 20% but 2x the boost.. something is wrong. I had a 92 gmc 350 on propane ( dual fuel ) with a paxton super charger and there is no way that it would take double the boost to equal what it could do on gas.

 

[gunnerthesnowman]

I was thinking more like 20% but 2x the boost.. something is wrong. I had a 92 gmc 350 on propane ( dual fuel ) with a paxton super charger and there is no way that it would take double the boost to equal what it could do on gas.

OK , maybe more like 1/3 more , it is a cheaper fuel ,but you do have to run higher boost to get same HP.
All i was try to get at is so many Quote boost # , = so much HP , not true if it is not set up right.