103 cu in upgrade

[StreetGlide N]

I'm considering upgrading to 103 with 255 cam, leaving the heads alone.
I always prefer to do my own wrenching and have never had problems building engines or transmission. Am I kidding myself on this project since I have never dove into a new 96 engine? I have the SE tuner system and I assume can find a map that matches this combo close enough to allow a break in period before taking it to a dyno. Right now the bike has SE air and Rush slip on's. Rest is all stock.
What should I expect from that cam, smooth idle like stock or is it going to lope on idle. Should a higher idle be used with this cam and also is there really a need for compression release with this cam?
Thanks in advance for the help.

 

[StreetGlide N]

Thanks for the reply and info Hobbit

 

[robertc]

I did the 103 kit with the 255 cams and the cams are nice for the low end torque however I would strongly suggest doing head work as I was a bit disappointed with the end result. After the kit my Hp was low 70's and Tq. low 90's on the dyno. The same kit was installed in a friends bike and he installed S.E Heads on his build...Huge difference! His Hp and Tq are both in the 90's... I should have had the heads done while it was all apart. I think you would be happier if you get the heads cleaned up in order to get the most out of your build. In my bike the larger displacement didn't make much difference although the cams did help. I now realize that mild head work really helps the engine breathe and perform much better.

08 Ultra w/103 kit (255 cams)
Hooker tuned flow exhaust
new race tuner
oil cooler