I have a 12' DWG with the 103
Exhaust, heavy breather and tuner plus 3 hours on the dyno and I'm at 76hp and 96tq.

Talked with the guy at the HD shop about ideas but wanted to get a broader feel from you "experts".

So...what are the best options for more power?

Cams?
Upgrade to 110? (with new cams)

Or...the expensive obvious choice of the 120R...and if go that route, how much can I expect to get from my stock/new 103 motor?

Lot's of questions and I'm open for all ideas!

Thanks!

 

The factory 103" is a great starting platform for a budget build and you have already done most of it. Adding a set of cams, like the HQ 500s or Andrews 26 will get you close to 100hp and well over 100 torque, probably in the range of 105 to 110 torque depending on which exhaust you are running. Best bang for the buck.

Do not go to 110" it is a waste of time and effort for little gain. Now, the 120 is a whole different story but you will be spending in the range of $7k plus before it is all said and done.

 

Talk to Fuel Moto or Frank from Drago's bike works. These are top notch operations.
What Frank doesn't know about making power hasn't been invented yet...

 

couldn't agree more.

The moco has done a bunch of work for us in the last few years. They've installed both a stroker crank and a big bore kit for you, and the 07-newer heads flow pretty well. You've also got ACR's and an oil cooler, so really, all you need is a decent intake and exhaust, a mild set of cams and a tune and you're ready to go. 90+/100+ is practically a no-brainer.

A few years ago, we had to start from a TC88 with 4" stroke and a 3.75" bore, lousy cam tensioners, heads didn't flow all that well, no oil cooler and no compression releases. If you wanted a 100/100 motor, it took a fair amount of time and cash. Now, you can get dang close with just normal stage I improvements and the right cams.

If you've got a few bucks burning a hole in your wallet, look at the 103 stage III or stage IV kits. SE259 cams and 10.5 pistons, along with some other goodies. The stage IV kit includes ported factory style heads, and is a good deal at about 2 grand from the online discount dealers.

 

How much of a power increase are you looking for??
The 103" can certainly be modified to come up to a level that will wax your bud's 110"s, and same goes for boring that to a 107"er.
A 107"er set up and tuned correctly, can/will push off 120/120 plus, as dyno evidence accross the country, has shown with our engines.
Usually that's plenty of juice for mucho fun, without busting the bank.
Dalton, we are sending one of these to Atlanta tommorrow.
I will say that he is a gentleman,(and thank you!) and we are proud to know him!!
Scott

 

The 103 kit can makes good power we have built a many of these with hd 103 kits we run
SE forge pistons 10.5
Tman 555 or Andrews 54 or Dragos S/C/S 570 cams
DBW Stage 1 cnc port or stage 2 with 1.9 int 1.615 exhaust cnc port
10.5 or 10.8.1 and you can see power gains of 110/116hp and 122/128 tq cf std smoothing 5
With a good exhaust and good tuner.

Also like others have said you can take a 107 and get 125/130hp and 125/130 tq out of them.....

My 2

 

Use what you got for a starting platform. the 103 is a great starting place. 10.5:1 pistons are cheap 225.00 from LSHD. just pick a cam and header. Get a little head work while it is apart. you should get great results for very little $$ spent.
You could also just stick a header on it and a cam swap with a tuner and this would be a nice running bike.
for a header Call Frank you wont get a better header. Coated inside and out and you just can't beet his price.


Jim

 

Some great advice from many, thanks!
Including install/labor:
-How much $$ for full blown 103 kit (As Drago mentioned, including heads, pistons, cams and CNC porting?
-How much to just go to a 107?

 

If the question to me here you go.
We have our 107 stage 1 kit on sale. This includes....
New cylinders and forge pistons
All gaskets needed.
Pushrods and tubes
And send in heads for cnc porting.
And cam choice of
Tman 555 or Andrews 54 or Dragos SCS 570 cams.
$1640.00 sale until end of Halloween.
Shipping is extra...

 

Jamie @ FuelMoto has tuned the Wood 555/107" with our little Stage II Head combo, to an amazing 110 hp/127 ft/lbs.
Incredible bagger combo, with the torque delivery right where you can use it.
Jeremy, @ Bowling Green H-D, has also shown 115/120 from the 107"/our Stage III Head with Bob Wood's tiny TW-6-6 cam, as well as 120/121, again with our Stage III Head/107"/T-Man .590 cam.
Jim Kennedy of Paradise Performance, Matoon Ill, has had a couple of our 107"ers on his drum. 120/120 was one, and another equipped with a Wood 9B went mid 120's square if memory serves me correctly.
Just a small example of what we churn out of our shop, but again, we've been doing this for almost 30 years.
Scott