+ on the 48
You can always build on it........

 

It's not a matter of gaining 3%. The whole package will make it where you go from .8 HP per CI to 1.15 or so HP per CI.

If that doesn't turn your crank, just buy a S&S 124 crate motor. You will have about $7500 in it, but it will be a once and done deal.

OR you can go for the S&S 143, or you could turbo charge a 143..OR.....

 

I just had a Fuel Moto 107" Big Bore kit installed in my 2007 EGC. 113hp/120tq.
Nice thing is you don't need to go with new heads and there is no need for bottom end work. Prices are very reasonable as it is a core exhange. I got the numbers above with the Level B heads which up the price a bit.

Check them out. You can buy the package and do the install yourself, with the help of their 12 Video to walks you through it, or you can have them do it. You won't get better support than Fuel Moto.

http://www.fuelmotousa.com/107-inch-big-bore.html

 

Oldhippie.....
All looks good, and considering same.

For me, going from 103" to 107" has very little to do with power increase, in my situation. I believe the higher compression is more at play.

 

No need for 107. Them 4 cubes aren't a big deal. Your stock heads can be flowed and milled for compression for the cost of bore and Pistons. With proper exhaust, cams and tune will run with most 107s. Lots of good head guys that can point ya to a good combo. But if ya just want to cam your 103 I'm a fan of 57s.

 

If you're already thinking a stage 2 won't be enough, it most likely isn't going to satisfy you. Your most cost effective route is to find a good builder who can either port the heads himself or knows someone that can. 107 kits are not magic, the reason they work so well is because everything is set to work together, mostly being compression ratio. Frank Dragos @ Dragos Bikeworks can give you some good advice & ideas on the direction to go, his shop is in Machesney Park IL. There are many others in the upper Midwest also that can do a good job, just thought he might be the closest to you. If you can do the work yourself a bolt on 107 kit isn't a bad idea because all of the details are already figured out for you, such as piston deck height & head chamber volume to set the optimum CR for the cams you choose for your particular riding style. You are correct in thinking that a properly set-up 103 will only be 3-4 less HP & TQ than a 107, that was the reason I asked how many miles were on the bike. You should easily be able to get 105-110 HP & 115-120 TQ out of a 103 with good head work & proper cams. Ask for dyno runs for the package you are advised to because all the best parts in the world are no good if the combination doesn't work well together, good luck in your build.

 

Ok guys.......I think I'm on the right path.

Ported cylinder head milled for compression.
Cam to work with new head
Programmer

Do clutch springs need to be changed? Also can I remove cat from factory head pipe and achieve decent results.
Seems like stepping up to a pipe with crossover would be something that be be more necessary when squeezing h/p or larger cubes?

 

A 2-1 will net the most HP/TQ if you can get over the non-trad. look?

 

A 103" done RIGHT will be very close to the 107".

 

T-Man 555 TQ cam only have about 550 miles on the bike with this cam and loving every bit of it.