Ok my 2008 street bob has been bored to 103" and stuffed with kb 10.5.1 pistons. Heads have not been touched except to replace the front on with an oem one. Cams are a used set of 255. Also dyno tuned witha power commander. Power is pretty good but never enough. Does anybody know how or can tell me how to find out what my CR is with this kit? I am looking at installing an andrews 54h or 67h. Andrews tech suggested the 67 from my aggresive riding style. I would like to massage my heads later as money can afford, but i want to change the cams now. I know i probably need new springs with either cam but am looking for opinions, mainly exp with these cams and any numbers and/or dyno sheets i could view. Sory this is so long but wanted the details out there because the internet doesn't allow a lot of time on where i am at. Thanks in advance for any help/guidance or criticism.

 

here's dyno graph from my old 103 consisting woods 7h cams, with wiseco 10.5:1 pistons, fatcat qb, bored stock tb,tts-mastertune in a 07 streetbob. go to bigboyz website and they have calculators that will get you close. woods now has the tw-555 which has a little more duration and a tad less lift. i also think it has a slightly later intake closing, which is more of a direct comparison to the andrews 54.

 

You have the compression to run the 67 and are overpressuring the 54 or the SE255. The 67 will be a good choice especially later with a light head mill and porting. If you were looking at Woods grinds that would be the TW8 to compare with that 67. A spring change would be wise for the 67 and mandatory for the TW8

 

Thanks for the advice. I have only seen one dyno result from the 67 cam and wow. It was just a straight line of torque from 2k to 6k rpm. Above 100 tq the whole time. Horsepower was just steadily climbing. Almost too nice to be a real dyno sheet but it was in a 110 so will see how it goes in a 103. Thanks again for the advice. I am going with the 67 but will be some months before i am home to post results.