103 Install

[ajaxastor]

Hello all, this is my first time posting. I’m hoping someone can help me make a decision on a 103 BB upgrade. I have a 2007 heritage classic with the stage I kit and race turner. Would like to get more mid to high range power with the biggest bang for the buck.

I’m trying to decide whether to go with the standard HD stage II 103 Install using the SE 255 cam or take it one step further and go with performance heads (maybe SE CNC Ported HTCC boosting to 10.5-1) with a little bigger cam (maybe Andrews 37G, SE 251, or SE 257).

I’ve been told that the stage II kit will boost HP to high 80s and torque to high 90s, not bad, but I’d like to get to the mid to high 90s on HP.

Also trying to decide between the FatCat 2-1 exhaust and the Thunderheader.

Any thoughts would be greatly appreciated.

[Dyna Jim]

Hello all, this is my first time posting. I’m hoping someone can help me make a decision on a 103 BB upgrade. I have a 2007 heritage classic with the stage I kit and race turner. Would like to get more mid to high range power with the biggest bang for the buck.

I’m trying to decide whether to go with the standard HD stage II 103 Install using the SE 255 cam or take it one step further and go with performance heads (maybe SE CNC Ported HTCC boosting to 10.5-1) with a little bigger cam (maybe Andrews 37G, SE 251, or SE 257).

I’ve been told that the stage II kit will boost HP to high 80s and torque to high 90s, not bad, but I’d like to get to the mid to high 90s on HP.

Also trying to decide between the FatCat 2-1 exhaust and the Thunderheader.

Any thoughts would be greatly appreciated.


I'll only comment on the TH versus Fat Cat, I've had both, and the Fat Cat won on the dyno hands down.:peace:

DJ

[ajaxastor]

Thanks DJ, would you recommend the race baffles on the Fat Cat?

[FLHTCUI2004]

I went with the 95 kit, Andrews 37 gear driven cam, and Vance/Hines 2into1 propipe hs. I had to get used to my Ultra only having one exhaust pipe! But, i actually like it better. . cleaner looking on the left side, and sounds/runs wonderful! My next step will be to take my heads in and have them ported, though I am still investigating that option.

I am extremely happy with this configuration. The one mechanic I have come across that I trust, actually suggested not doing the big bore, rather, claims to get more bang for the buck with getting the heads ported by a qualified tech. He claims that the 88's are only running on 70% efficiency, new heads should increase that considerably, maxiumizing lowend torque. Adding bigger cube's won't help that much unless you change the amount of flow you get through the heads. . .he told me that my putting the big bore kit in without changing the heads, actually hurt me a bit. . . though the Andrews cam helped that problem. Needs more flow into the cylinder. . . my stock heads don't do it.


I am finding that there are a lot of people out there willing to take your money to increase your power. Be careful, the wrong configuration will add lots of grunt, but destroy reliability of an otherwise solid engine. I am very happy with what I have done. When/if I do the heads, it will because I need to freshen the motor anyway, (I have 61,000 miles on her now) so I'll do pistons, rings, and the heads at the same time. That is a 1800 dollar upgrade and will supposedly give me 100 pounds of torque. . .at 2500 rpm. . where I ride a lot.. . .and a fresh engine!

Good luck!

[ajaxastor]

I know what you mean about reliability. I have been a little worried that increasing the compression ratio to 10.5-1 with the new heads may shorten the life of the engine. I would also like to keep the bike "street friendly" so i don't want to put in a cam that sacrifices the low end torque for high end HP.

[Heritage Dru]

Good advice from both guys: go with the fatcats, change your cam (I wouldn't go with HD, I'd go with andrews although from what you're describing the 37G may not be quite aggressive enough, you may want to consider the 44G) do the headwork it is good bang for the buck, and consider changing your ignition to maybe a crane or dynatek. (my first choice would be the crane. good luck

[Fatboy395]

I had the 103 Stage II for EFI kit installed on my FLSTF '07 Fatboy. It includes screaming eagle slip ons (loudest HD makes) and air cleaner. The labor averages $550 with the kit being $1200 from HD. About a 10 hour job at the dealer for a standard upgrade. Get an off season discount from the dealer and you got yourself a good deal.

The increase is about 20%, is not a radical engine rebuild therefore not sacrificing reliability in the long run. You will notice the difference! You will not be disappointed! The 96 made me smile , the 103 makes me grin when I ride now.

103 cc 1690 78 90 (Not Dyno Tuned)
96 cc 1584 65 75

The 110 looks and sounds great but requires much more labor time and is not cost friendly for sure.

[ajaxastor]

I took the bike in a couple of weeks ago for the work. After quite a bit of soul searching (not to mention funds searching) I decided to get the headwork done as well. So I ended up with --

HTCC Pistons, HTCC CNC ported heads, 1690 big bore, TR590 cam (T-man Andrews product), 50mm TB, SE Clutch and 2-1 Fat Cat w/Race Baffles.

I took it into the dealer for winter work (20% discount) hoping it would be out in a week, but of course, they still have it. Seems like its taking forever!! I wanted to get it broken in and tuned before the snow started to fly, but living in Michigan I'm rapidly running out of time. It may be next spring before I really know what the bike will do!

[Fatboy395]

I took the bike in a couple of weeks ago for the work. After quite a bit of soul searching (not to mention funds searching) I decided to get the headwork done as well. So I ended up with --

HTCC Pistons, HTCC CNC ported heads, 1690 big bore, TR590 cam (T-man Andrews product), 50mm TB, SE Clutch and 2-1 Fat Cat w/Race Baffles.

I took it into the dealer for winter work (20% discount) hoping it would be out in a week, but of course, they still have it. Seems like its taking forever!! I wanted to get it broken in and tuned before the snow started to fly, but living in Michigan I'm rapidly running out of time. It may be next spring before I really know what the bike will do!

Wow! What will the gain in hp be with the rebuild. It looks like you did your homework. The only thing you didn't get was bigger grips to help you hold onto that monster. LOL I opted for the kit since it was the easiest way for me to get it done. Mechanics from HD seemed indifferent on information for rebuilds. good Luck