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Discussion Starter #1
I have a question about cams for my '07 FLHRS. I will really appreciate any reactions to my question/dilema.

I have a 2007 FLHRS that I purchased new in February 2007. Before taking delivery in May 2007, I had quite a bit of performance and non-performance (e.g. replaced stock handle bars with Carlini sweep bars; custom gauges, etc.) work done to the bike. On the performance side, I added a Screamin' Eagle Big Bore Stage II kit for EFI Models (this increased displacement from 96 CI to 103 CI, added SE-255 cams, big bore cylinders, big bore flat top pistons, etc.). I also added Rinehart True Dual performance exhaust and a ThunderMax Autotuner.

The bike runs well; on the dyno I get 85 HP and 102 TQ. I am planning on putting new heads on my motor; specifically HR Part No. 16500013A - Screamin Eagle Pro CNC Factory Heads with Valve Upgrade.

My goal is to get better low to mid range torque than I am getting. My dyno curve suggests I am not getting enough air and I expect the new heads will address that.

Depending on who I talk to, I am being told that when I switch to the Screamin' Eagle heads I should also change cams - from my SE 255 cams to SE 585 cams, Red Shift 575 cams, S&S 570 cams, or maybe T-Man 555 cams.

I understand that, as a general proposition an early intake closing (less than 30 degrees after bottom dead center) will result in good low end torque, and a medium intake closing (30 - 50 degrees ABDC) will result in good midrange torque. The thing is, the SE 255s have an intake closing of 25 degrees ABDC, which is an earlier intake closing than any of the other cams that are being suggested. I know there are things than intake closing to consider, but until I have a better understanding of those other factors, I find myself questioning whether I should stick with the SE 255s or switch to one of the other cams that are being suggested. As mentioned above, my goal is strong low end to mid range torque. Horsepower increase, if achieved as a by product is fine of course, but I am after the improved low to mid range torque.

Any and all reactions/comments/suggestions will be GREATLY appreciated!
 

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I would highly recommend posting this question in the TECHNICAL/ PERFORMANCE section. Also, try and do a search with key words in that forum. I typed in "cams" and came up with 28 threads.
 

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Discussion Starter #3
Cam Choice Help

I have been reading a number of threads to try to better understand how cams work and factors to consider in choosing cams, but I have a long ways to go and would appreciate the input of members who have way more experience and understanding than I do..

I have a 2007 FLHRS that I purchased new in February 2007. Before taking delivery in May 2007, I had quite a bit of performance and non-performance (e.g. replaced stock handle bars with Carlini sweep bars; custom gauges, etc.). On the performance side, I added a Screamin' Eagle Big Bore Stage II kit for EFI Models (this increased displacement from 96 CI to 103 CI, included SE-255 cams, big bore cylinders, big bore flat top pistons, etc.). I also added Rinehart True Dual performance exhaust and a ThunderMax Autotuner.

The bike runs well; on the dyno I get 85 HP and 102 TQ. I am planning on (1) putting new heads on my motor; specifically HR Part No. 16500013A - Screamin Eagle Pro CNC Factory Heads with Valve Upgrade, or (2) sending my heads to Big Boyz in Augusta Maine for porting (I live I Portland Maine).

My goal is to get better low to mid range torque than I am getting. My dyno curve suggests I am not getting enough air and I expect the new heads will address that.

Depending on who I talk to, I am being told that when I switch to the Screamin' Eagle heads I should also change cams - from my SE 255 cams to SE 585 cams, Red Shift 575 cams, S&S 570 cams, or maybe T-Man 555 cams.

I understand that, as a general proposition an early intake closing (less than 30 degrees after bottom dead center) will result in good low end torque, and a medium intake closing (30 - 50 degrees ABDC) will result in good midrange torque. The thing is, the SE 255s have an intake closing of 25 degrees ABDC, which is an earlier intake closing than any of the other cams that are being suggested. I know there are things than intake closing to consider, but until I have a better understanding of those other factors, I find myself questioning whether I should stick with the SE 255s or switch to one of the other cams that are being suggested. As mentioned above, my goal is strong low end to mid range torque. Horsepower increase, if achieved as a by product is fine of course, but I am after the improved low to mid range torque.

Any and all reactions/comments/suggestions will be GREATLY appreciated!
 

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Discussion Starter #4
RottnRam: Thanks for the suggestions. I have reposted in the PERFORMANCE section and I am reading some of the posts that result from the "cams" search. Thanks again!
 

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Having your heads worked (By a Pro) is the better choice I think, and more bang for the buck.
It is a system (recipe),
Heads worked to match the compression and cam choice.
Intake and EXHAUST to work with the above.
Then a Tuner to knit it all together (That T-MAX you have is good equipment)
I do not see what your static compression is going to be set at, big factor in cam choice.
The SE 255 leaves a lot on the table.

SS 570, Andrews 57, T-MAN 555 Torquester all good cams for reliable 103” touring builds, that last one has a high and wide torque curve. Google is your friend search for Dyno sheets with those components.

There can be a lot gained with the right 2 to 1 exhaust if you can live with one.

D
 

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Discussion Starter #6
Thanks Doug53. I spent quite a bit of time today talking with one of those Pros you are talking about - Bruce at Big Boyz in Augusta Maine - and it looks like I will be sending my heads off to him for porting . . . and the cams you mention are all in the running. Thanks again Doug53!
 

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Jeremy at Bowling Green HD, Bowling Green Ky, tuned a 103" with our heads to 111/116 with a little Wood 6, .510" lift, 10.2 cr.
Hit's hard on the bottom, and carrys great torque all the way out.
But then again, we've been doing this for 30 years also.:)
Scott
 
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