2 much comp?

[liquedfire]

my shee is runnin at 175 psi??

 

 

i know stock it should be around 120 but shit 175 to much??? :shoothead:

 

just askin

 

 

 

thanks

 

 

glenn

[watkins]

my shee is runnin at 175 psi??

i know stock it should be around 120 but shit 175 to much??? :shoothead:

 

just askin

thanks

glenn

 

Well... depends on what you are looking for... to run the bike on pump gas then yes 175lbs psi is too much... or if you are looking for too much for a non-welded stock crank... well there isnt an exact science to that one, some cranks will work fine some will fall apart you will just have to ride it and see. How are you putting out 175 psi, with just a milled head that sounds kinda high.. are you sure your compression tester is good?

[blueshee03]

Well... depends on what you are looking for... to run the bike on pump gas then yes 175lbs psi is too much... or if you are looking for too much for a non-welded stock crank... well there isnt an exact science to that one, some cranks will work fine some will fall apart you will just have to ride it and see. How are you putting out 175 psi, with just a milled head that sounds kinda high.. are you sure your compression tester is good?

 

i agree it depends on how and what type riding you do.remember the more compression you have the less topend you have.the higher the compression also comes the need for higher octane to help take care of detonation.as for a welded crank i believe trueing and welding crank is a great idea in any banshee whether its stock or highly modded.

[[email protected]]

170 psi is not to much in my opinion, however you should be running 50.50 atleast . Im running 220ish psi and im running straight 112octane .

[RILS]

my shee is runnin at 175 psi??

i know stock it should be around 120 but shit 175 to much??? :shoothead:

 

just askin

thanks

glenn

I would say that 175 is a good choice,but i would run atleast 106octane.

[2003LimitedBanshee]

Well... depends on what you are looking for... to run the bike on pump gas then yes 175lbs psi is too much... or if you are looking for too much for a non-welded stock crank... well there isnt an exact science to that one, some cranks will work fine some will fall apart you will just have to ride it and see. How are you putting out 175 psi, with just a milled head that sounds kinda high.. are you sure your compression tester is good?

 

I got to 175 psi when I put my NOSS head on with 20cc domes. That's at 1980' feet by the way. Over 190 psi at sea level, with a new Snap-On compression tester I might add. Are you running any timing advance? With my compression and 4* advance I run straight Trick 116 just to be on the safe side.

[liquedfire]

nope i just milled the head and put a fresh set of pistons

 

 

i left the piston clearence at .0024

 

and it only like over 100 octane

 

thanks for the help

 

 

 

Glenn

[mouse]

i agree it depends on how and what type riding you do.remember the more compression you have the less topend you have.the higher the compression also comes the need for higher octane to help take care of detonation.as for a welded crank i believe trueing and welding crank is a great idea in any banshee whether its stock or highly modded.

i got a question then i have the nose head with 18 domes at 1000 ft. elevation and im at 173 compresion runing turbo blue i beleave its 110 octone whic h is good. But my question is how are you lossing top end and should i change my domes to get a lower compresion . Just wondering how it all works. thanks

[RILS]

i got a question then i have the nose head with 18 domes at 1000 ft. elevation and im at 173 compresion runing turbo blue i beleave its 110 octone whic h is good. But my question is how are you lossing top end and should i change my domes to get a lower compresion . Just wondering how it all works. thanks

You do loose a little topend by running higher compression,however there is a good medium where the loss is worth the gain i guess you could say.I prefer 170-185psi and ive heard a lot of builders like this range also and a lot of people here run in this range.In my opinion anything over 200psi on gas is hurting more than its helping.

[2003LimitedBanshee]

i got a question then i have the nose head with 18 domes at 1000 ft. elevation and im at 173 compresion runing turbo blue i beleave its 110 octone whic h is good. But my question is how are you lossing top end and should i change my domes to get a lower compresion . Just wondering how it all works. thanks

 

Short answer, the higher compression makes the bike slightly less efficient at higher RPMs making for a slight decrease in top end power. The bike will not want to turn quite the RPMs with the higher compression etc... But, you should be noticing a good increase in the bottom end torque with compression in that range.