i have a pc scilencer, its big old and falling apart. the rivets are widening and the core is loose. ill repack it and weld it till christmas. my question is which scilencer should i get my bike is a 96cr250 w/ pc pipe n scilencer. would a shorty benifit the porting of this bike stock? its low to midrange. would it require different jetting? if so where do shorty scilencers effect the jetting?