As promised here is my review of my 2008 FireCat with updated limbs and Cat2 cams.
I got the limbs Dec. 17th and installed them using the original Cat cams and new Roto cups. The limbs rely on machined side plates on the Roto cups for alignment. They are not drilled and pegged on the underside of the limbs so they can "float" longitudinally in the Roto cups. They only thing I can see to keep them from sliding is the limb bolt. This may work. Time will tell.
The Roto cups sit in the riser the same as the old ones so no shifting should occur here. The limbs are narrower and the limb forks so shorter axles are needed (included in the package). There are two thin (1/16") washers on each side of the cam. Cam lean was very evident and very bad at full draw. A call to Joel at Martin confirmed that the older Cat cams are not compatgable with the new limbs. He sent me a pair of 2010 Cat2 cams which I installed in about 15 minutes.
Bow specs fell within a reasonable proximity to factory with the ATA being 32 1/4" (both sides) and the brace height being 6 7/8". Draw weight peaked at 53# with 50# (1M) limbs.
At first glance there appeared to be no cam lean and a straight edge held along the side of the cam and parallel to the string confirmed that there is virtually no cam lean at rest. I removed the cables from the cable slide and checked again, with the same results. At full draw I could see no cam lean so I had a friend look from behind me as I stood and aimed. He said he couldn't see much of any cam lean at full draw. So far, so good.
Now for the tuning. I tied on a nockset 1/4" above square and moved the centershot in toward the riser. The centershot is closer with these new limbs, about 1/8". Put in a peep and took a shot at 10 yards with my old 20 yard sight setting. It was off a little with the first arrow hitting low in the X-ring on a Vegas face. Pretty darn close for a thrown together remake.
Bow is quiet and performing as well as can be expected. More work to come, as I don't have properly spined arrows for my setup. Bare shaft at 15 yards and paper tuning both show the same thing. Nocking point is right on and left tear through paper (stiff arrow for me). Need new arrows anyway with a softer spine.
Here some info about the new Cat2 cams. The cams have been redesigned to minimize cam lean. The cable track around the inner part of the cam is machined in spiral, meaning that as the cam rolls over the cables tracks deeper into the physical center of the cam. This is what helps with the cam lean as the pressure from the cable is shifted more toward the physical center of the limb forks, evening the pressure. The spiral (or helical if you will) isn't real noticable till you look hard, but it's there. It appears to work well.
The modules are different, too. First off they are not a silvery color, but more of a charcoal. They are narrower with a deeper groove for the cable to track into and the outer edge is rounded where so many people were getting severe cable serving wear. Also, there is a little gap between the cable and the module (at least on my bow) so this should help, too.
My shooting keeps going down hill along with muscle depletion so shooting test won't mean much to people, but with the bow set for 26.5 " draw, 42# of draw weight, and a 275gr arrow the bow chrono's at 256 fps. With some tweaking I should be able to get 260 fps to 265 fps out of it.
The only other thing I would say is that it has new Stone Mountain strings (Martin). I put a peep in right away and am having no peep rotation as of yet, with approximately 100 shots through the bow yesterday. My shoulder hurt today.
OK, now I'm open to questions and/or suggestions.