Thanks Badger, I am quick to freak-out based on my serious lack of experience on this subject and the serious expense these mods are to my pocketbook. I am glad to hear the change to 54 is "in the ball park" and that they may have some reasonable explanation.

Dawg - are you suggesting that they installed the 54 with the 4 degree advance or that I can do that later?

 

Who picked the 37s? Is that what you picked and wanted or is that simply what they recommended to you?

If you picked those cams and they installed something different I'd be pissed. This is the real issue.

If you were simply going by their recommendation then it's not as big a deal, as you would have probably ok’d the 54s if that is what they originally suggested. If I had to pick between those two cams for my 103 Limited, I’d probably pick the 54s.

The two cams (37 vs. 54) are slightly different but that difference is not huge.

The 54s have .045 more lift (.510 vs. .555). In theory, this should result in slightly higher peak numbers.

The 54s intake duration is 2 deg. more than the 37s (238 vs. 236); and the 54s are 3 deg. retarded relative to the 37s (16/42 vs. 18/38). In theory, this should result in slightly higher peak numbers and a torque curve a little to the right of the 37s.

The 54s exhaust duration is 2 deg. less than the 37s (238 vs. 240); and the 54s are 2 deg. retarded relative to the 37s (43/15 vs. 46/14). In theory, this should result in slightly lower peak numbers and is probably a wash on moving the torque curve.

Overall I think the 54s will produce slightly higher numbers and have a torque curve slightly to the right of the 37s although I don’t think the differences will be that significant.

These are only my thoughts. Even though I think I have a rudimentary understanding of how camshafts work, I’m definitely not "the" expert in this area.

 

I agree with 2B1s. The real issue is the 'reasoning' the shop installed something different than what you understood was supposed to be installed.

That said, I've had the 54s in my 117 (tested along with three other cams, one of which was very similar to the 37) and am having a 107 build with the 54s as well. The cam tests I've seen on my bike showed the 54 built a longer duration torque curve than the 'shorter' cams.

You are correct in that the CR needs to be closer to the 10:1+ for the 54 to do its work. IMHO YMMV. Good luck; and let us know what happens and what you think.

 

If this was in an Ultra I would be unhappy but a slightly lighter SG can handle the 54's OK. You could look at it as an opportunity for a comp bump sometime down the road....

 

I'm not suggesting they installed the 4* gear, I'm suggesting that you can always add it down the road. I think you will still be fine with the 54 without the 4* on it.

 

Thanks for the quick and helpful responses, especially 2black1's which was a great breakdown on the differences.

My decision was based 80% on my research and 20% by the fact that the shop had suggested the 37 initially and I wanted them to use a cam the had significant tuning experience with. At the end of the day, I will speak to the owner shortly and get his explanation for the change. Happy to have the option of a compression bump down the road with a 54. Will report back with the actual dyno sheet and first hand experience on the bike.

What a great place this forum is; I have had nothing but outstanding advice and information at my fingertips. Hopefully, I can give something back sometime in the future.


woke up at the crack of dawn excited as a kid to go pick it up.

 

If the 37's would have made you happy, the 54's should also. The 54's are slightly more radical than the 37's. They are slightly less radical than the Woods 555 that is very popular here. I'd be happy with the 54's or 37's I'm sure.

It is weird that there was a switch though...

 

Well after a long conversation with the shop, turns out they contacted Andrews directly and Andrews suggested the 54 over the 37 for my setup. Leaves me room for a compression bump down the road.

Overall really happy with the results. Attached is the dyno for anyone who is interested. Thanks again to everyone who responded.

 

You sure have to be crankin some serious rpms to get that horsepower and torque, don't you? Are you at all worried about having a "heat monster' on your hands?

 

54's are a bit more of a cam.
You should be real happy!!
Better choice..