sorry its been a while 27 not 23...23 lighter bikes.. I get # mixed up dyslectic,,,,, came on at low end did sacrifice on high end.. get one that closes intake about 30 deg...
I know IF the intake Closes Earlier you get More LOW End torque Like ultrat says..
I am going "Playing" with a 4* sprocket on/for my 09 FLHR.. Idea is to MOVE the intake to Close at an earlier Number.. for the torque to come on a bit earlier.
When I put in SE255 cams, I Like the results BUT would rather they come on a little earlier for my Heavy Bike..
I am going to order the andrews 4 degree +- engine sprocket (17 tooth) and see what it does for my full stage One with TFI..
If it does what Steve 07 has done or close (he used SE254 cams with the 4* sprocket) claims Much More Low End!
I will POST a new thread when I find out "How It Works"
Part # that TQ1 furnished me is andrews #216323...
For your EVO, I believe you are right on track with the 23 or the 13 but NOT the 27 cam. REMEMBER most people Over Cam and that does not give better results,,, It Takes away!
EV23 = 10/30 on intake lift 498/498
EV13 = 15/31 on intake lift 485/495
EV 27 = 20/36 on intake lift 495/495
Proper compression and volumes are needed to get results with Bigger cams and usually the RPM band Moves Way Up where you don't need/want it for a heavy bike.
I would like the cam to start on the LOWEST RPM when Just thinking Cam!!
Especially on the heavy bikes...
I would go with the EV23 IMHO on the three that Could be used on your bike... The intake closes earliest! Along with the highest Lift.
signed....BUBBIE