you're really not comparing apples to apples here when talking about changing the twin cam 110 to a 117 and then comparing it to the M8 117.
you have the same cubic inches, but the M8 is a different motor than the twin cam. In a discussion with Fuel Moto about upgrades to my 110 (have already done their 110 upgrade), I was told I would be better off buying a new M8 bike to get the best numbers.

 

We have built a customer favorite 117" for many, many years now.
Our HMM Stage II CVO Heads
S&S 4 1/8" bore cylinder kit
Wood 9F cams
58mm t/body
D&D Borezilla.
Those will produce 135-140 hp and 140 ft/lbs....on a bad day.
Broad-band torque, great reliable, pump-gas fun.
Scott

 

...... i've seen HD shop invoices for a 117 kit at just over $5k, incl. SE tuner

 

Holy crap that would be a rocket ship. Is there a dyno sheet floating around for that? Just curious more than anything else. I really need to dyno my bike to see what I'm at.

 

Just my 2 cents worth. Seems like everyone thinks you have to install hi flow injectors and 58 mm TB on every build. I am researching installing a stage 4 kit and talking to zippers and moto,, they both say unless you are planning on 125 + HP, you can stay with stock injectors and TB. So you can save a few bucks there.

Now having said that, I believe if your build is 120 HP, you could get a few ponys with the hi flow and 55 mm TB but that is if you have lots of $$ or trying to budget and not have to buy a new AC..