I want to purchase a pro-circuit T-4 silencer and K&N. Will I still need to re-jet the carb with a stock motor? Thanx for your help.

 

yeah....went one size up on both carbs.....
I think it was 145-140 or 150-145 something like that...didnt put in new needles tho...dont need em...fiddle with the needles a bit.. I think I moved em up one click... this is in jersey at sea level....

full exh is a diff story

 

With the slip on your increasing exhuast flow and with the K&N you increasing air flow so you need to rejet to icrease the fuel flow to match. This also gives you the biggest power increase for these mods. When I did mine the I did the rejet but didn't get the most out of it until I adjusted the needle one notch richer. the pilot jet controls the first quarter of your throttle response and the main jet your last quarter but the needle controls the entire area inbetween. I'm no mechanic I'm just not totaly clueless either I got a haynes and clymer manual and had no problems. Good luck let us know how it works out for you.