I was wondering if anybody has done any head and cam changes on the new '07 motors and what results. I have bought a set of SE twin cam perf. heads and was mostly undecided on cams. Andrews 31g or 55g. I will have 10.3:1 comp. I like to ride hard sometimes but I also carry a passenger alot. Also thinking about BB 103 kit also. I know these heads don't need the same type of cams as a stock head being the intake to exhuast flow is better. Don't like the S&S cams that have ave. 15 degrees more on the exhuast. Mostly, does anyone know how "choppy" the 55g cams are. I hate the smooth idle my bike has now but I don'y want something that chugs in high gear at low rpms. I had an 06 sportster 1200 and it sounded and ran much better. I,m just trying to get this bike to run better than that.

 

The only differance between '06 and '07 is the stroke. Longer stroke makes for more displacement and better torque potential.

The stock heads are really quite good. Even for a high performance street build, all they need is a small amount of port work at most. For moderate performance (anything less than about 5K rpms'), they don't seem to need anything. IMO, the aftermarket/SE heads don't provide enough bang for the buck to make it worth while.

Stock compression is still too low, IMO. Bump the compression up with new cast pistons to get effective cylinder pressures around 190'ish. If you do that, you might as well bore the cylinders for more displacement. 10.3 staticmay or may not work for you, depending on cam choice and where you ride.

Cam choice is tough. With the new design in '06, there are not a whole lot of choices. Of course, there's a decent selection from SE. Some of the aftermarket (Andrews) are advertising cams, but I understand there is a delivery problem. I'v not heard yet of somebody actually installing one on a new bike. I'd call and ask about availability.

To get that choppy idle, you have to increase the duration of the valve events. Unfortunatly, that usually means a late closing on the intake valve. That may put your cylinder pressure too low, or place the power band too high for you.

The best thing for the right sound is - of course - the right exhaust. That's really tough, because it's very subjective. You just have to try a few and see what you like.

 

I have just built my 07 Ultra with the following:

Bored the original jugs out to get 103" (saves you about 125$)
HD 50mm Throttle Body
10.5:1 HD Flatop Pistons
HD CNC Ported HTCC Heads
Rinehart True Duals
PCIIIusb
Green HF AC & Plate
And the key to this buildare the Woods TW-400-6 cams, narrow centerline, not a huge amount of overlap, but high lift and pure torque builders.
The difference in the exhaust, the cadence and the "pop" is very noticeable due to the compression increase and the cams.

Dending on your shop, you should be able to get this for around $4k no problem. I saved a lot, living in Ohio by waiting until the service dept. was starving for work, got 15% off all the parts and special deal on labor. Completed the build, a lot of snow on the ground, so will wait till spring to "run in" the motor and put on the dyno.

Cams are a personal preference, but ran Woods TW5G cams in my 03 95" RKC and with similar build as one just done, has 102hp and 115 TQ. I am expecting once I get a few miles on my Ultra and get it on the dyno a minimum of 115HP and 125TQ, may be pleasantly surprised as have been told the numbers could be quite a bit higher.

Have run Sifton, Andrews and Crane Cams, but prefer Woods, they build torque !

Bike is in a million pieces now, shipped all tin out for paint and installing a few other go fast and chrome goodies, have 28" of snow on the ground so have plenty of time to complete the project.

Good luck with your build - I really suggest you call the cam mfg to talk, whether Andrews, Woods, Headquarters or others to try to get the components to all "fit" and work well with each other.

 

I think the SE headsdon't get enough credit. With bolt in cams on an 88 they probably don't offer much.I'm probably going to do the 103".I also see people using bolt in cams used for stock heads with them. With thier bigger exhuast valve and better exhuast flow, probably don't need a cam with more exhuast duration and earlirer opening exhuast timing as bolt in cams usualy are. I only paid $600 brand new. To port, mill for more compression, intstall better springs and bigger valves why not just buy new. I,m new to harleys but I'll be doing the work myself. I've designed\built a few race car motors and other bike motors. It seems there is alot of different opinions on making power with a harley. A cam with a duration over 250 and less that 110 lsa is a radical cam for a street car but would make way more that 1hp per cu. in. I guess I was really asking if anyone ever used a 55g cam in a 103" 10.5 comp.and if it seemed to radical for crusing. Thanks for the info guys. Bob did that 204 cam work good. I might put this off for a wile and just bolt in a cam untill I get all the parts I need.