Hello all, I have a 17 FXDL 103. I am upgrading. TTS 150 cams, S&S lifters, S&S adjustable pushrods, and a HPI 55MF TB. My question is, can/ should I port and or polish my heads? Will it make a difference? I can see that there is a difference in diameter of the head and the new TB. Just wondering before I put this thing back together.
thanks

 

I would if I were you. That is if it's within your budget.

 

I would do it myself, I have done some car heads before. Aluminum and cast steel.
thanks for the reply

 

If you are even thinking about head work, I would leave it to a professional if you have never attempted it. Those head you got on that motor are very expensive and if you mess up, well enough said

 

take my word for it, a) have them ported
b) have it done by a pro! Kirby @VtwinRacing or Scott@ Hillside can help you out
c) Yes it is worth it!
d) Have it professionally tuned, and enjoy!
marco

 

You would've gained just as much or damn near by just some minor porting of the heads and stock 50mm throttle body. I know that's the route I'm going when my heads come off. Too big and you'll lose velocity and low end will suffer for a little more peak hp on a dyno.
I'd make note of your torque curve before and after.

 

If you plan on doing your own heads, replace the valves with AVnV 1.850 intake and 1.575 exhaust 7mm valves. Cut the throat on the intake valve seat to 0.050 larger and have a good valve job done. 35 to 37.5 degree top cut on the valve will help. AVnV valves will need new keepers and spring collars IIRC. Clean up the ports.

 

And I'd set the compression to between 10.2 & 10.5.