Hey thanks for reading . I have a 103 on a streetglide, rhinehart true duals, heavy breather, sert..just got it tuned and am pleased but thinking maybe a little more low end . My original plan was 30 tooth front pulley and 103MR ss cam. With head porting . After talking with my dad , he believes the engine would be unreliable after porting the heads and I read somewhere on here about the 96s and 103s running close due to heads having similar airflow . Would porting make the bike unreliable . And what would be some other options if so . Would a cam by itself make a big difference even with the stock head . It's hard to justify 700$$ for s&s gear drive cam with minimal gain ? .. thanks

 

Those ss 103mr cams run well with stock heads. Not sure about the reliability issue comment with headwork or the 96/103 comparison, but headwork, compression and bigger cams would show a major increase. There's a youtube bike with stock heads and 103mr cams with good dyno results especially for a softail. I'll look for it and post.

I wouldn't change the pulley with that cam either.

 

 

Thanks for the reply. I'm guessing my best bet is to throw the cams in and go from there . Was just trying to save on the dyno fees . Lol . As for the pulley, I was hearing that the Mr103s started pulling around 3 grand so I was thinking smaller gear for that extra pep off the line. But was worrying about the highway rpms as I do tend to cruise 80+

 

I've seen dyno sheets on this cam and it hits at 2700-2800 so the 30t pulley may be overkill and not worth the coin. And at hywy speeds the stock gearing will be nicer.

 

headwork should be done to match your cams.There are alot of better cams out there for low end grunt.example tman torq 555 with headwork, andrews 54 or 57 with headwork. also the compression has to be right for the cams to produce go to htt forum and look in dyno section also throw this question to them

 

If you're just gonna do a Stage II upgrade then stick with the MR103 it will perform pretty well. Ask forum member cdonis..... The andrews 48H is also a great low end grunt cam and carries very well to 5g's for the stock 103"

 

The Mr103 is a midrange cam. I liked the way the dyno sheet looked but was just thinking the 30t pulley would help out off the line but I would rather my rpms stay down on the highway . So we're thinking the cam would open it up without headwork ? I could always pull the heads later on .. I think my dyno guy is playing with numbers . With my current setup he's showing 88 hp and 108 tq . A little high right ?

 

No need for the gear drive kit. These mr103s are nice . In my opinion if I was doing the heads, and raising the compression I would skip any bolt in cam because your leaving power on the table.

 

Jfrench, bout 2800 the bikes pulling real hard to about 5300 or so. I have the counterbalanced motor so I'm losing a bit there. I don't lug the bike so it's a non issue for me. I've thought of a pulley swap but I'm not sure I REALLY need it. Two up with bags I'm probably close to 400 pounds total and no issues with the torque available. One up generally and have plenty of power to chew up tires and have buried the Speedo without a problem. Do I want more power, yes....need it to enjoy myself ...not really. Do your homework and get the most bang per $. Doing stuff in segments cost more money.