For a 107" build with a tw-8-6 cam what size throttle body and injectors would i need? Thanks in advance

 

That would depend alot on your heads and exhaust. But assuming you are not skimping on either I would say a 51 - 55 HPI should do the trick.

 

I will probably use a d&d fatcat with hillside stage 3 heads

 

If you want that to really cook, then a 55/58 HPI Max Flo, with the 5.3 gps injectors, and our Stage IV's.
That combo put the hurt on a very strong V-Rod out this way recently.
Scott

 

 

Scott, how much more would that combo produce over the stage 3's? I still want it to be streetable for the long trips

 

$100.00
Scott

 

So at what rpm would my torque peak with a 51mm tb vs a 55mm tb with the woods 8? would there be a drastic difference between the 2?

 

The 55 will show more throughout the rpm range.
Totally street friendy.
Folks install 58's on 107"ers all the time with great results.
Scott

 

will the intake runner need to be enlarged at all? or is stock ok? I think your stage 3 heads will work ok for me on this build. the 4's are a little over kill I think but I could be wrong