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Discussion Starter #1
So a 3rd option for aftermarket cams arrived this weekend with Fitzgerald motorsports advertising their Hellraiser cam set.

Scott is advertising a net lift of 0.490” and 0.470” for the intake/exhaust respectively and a duration @.05” of 258 and 250

Compared to that to the SE2 with
0.491”/0.465” and duration at @0.05” 258/260

Or Jones N/A St3
0.490”/0.450” and duration at @0.05” 260/258

He’s advertising a preliminary dyno testing showing a 13% increase over stock and 5% increase over SE2 on a 1250cc test bike with only an exhaust and a tune.

With that in mind any cam gurus still on 1130 have any thoughts on the performance potential for these cams for higher displacement motors: 1320, 1350, 1402, 1487, and up?

Original For Cam Guru’s post
 

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I was skeptical at first as I'm not a big peak numbers guy, but the power and torque these make across the RPM range appears to be pretty impressive. One thing I am concerned about, however, is that Jones recommends upgraded springs and valvetrain whereas Scott mentions his cams can be used with the stock valvetrain as a true drop in set of cams. I would have liked to have seen the #1 1250cc engined test bike he used dyno before numbers on video'd as the same back with the new cams video shows that the dyno isn't really loaded up at all. But I don't think Scott is out to get anybody and I'm sure he dyno'd the bike the same way with each set of cams.

I'll hold out for a bit, but 8-10whp across the board at over 5500rpm really is impressive. Props to Scott for going after something that is heavily sought after in the V-Rod community.
 

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I was skeptical at first as I'm not a big peak numbers guy, but the power and torque these make across the RPM range appears to be pretty impressive. One thing I am concerned about, however, is that Jones recommends upgraded springs and valvetrain whereas Scott mentions his cams can be used with the stock valvetrain as a true drop in set of cams. I would have liked to have seen the #1 1250cc engined test bike he used dyno before numbers on video'd as the same back with the new cams video shows that the dyno isn't really loaded up at all. But I don't think Scott is out to get anybody and I'm sure he dyno'd the bike the same way with each set of cams.

I'll hold out for a bit, but 8-10whp across the board at over 5500rpm really is impressive. Props to Scott for going after something that is heavily sought after in the V-Rod community.
You should be very skeptical about the valve spring statement (i.e. OEM is "ok") considering the lift similarities between Jones Stg 3 (actually I think Jones recommended his springs even with his stg2) and Scott's. Take it from someone that went down this road years ago with a high lift cam, a dishonest vendor, and a very high lift cam. Cylinder 6 (and the block essentially) was toast when a spring snapped and went into the cylinder at 5000 rpm.

Lots of formulas on the web if you can figure out the installed spring height, know the oem spring pressure, etc. I have no idea what we have stock as I don't think the naturally aspirated cams are worth the bother (or money) in the Revo (save money for forced induction honestly).
 

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Discussion Starter #4
I agree, if I’m taking the time to install higher lift cams I’m most certainly doing some head work, the least of which is upgraded springs. However (for the sake of argument) the SE2’s are advertised as drop in. Between the SE2 and the Hellraiser there’s +0.001” greater lift on the intake (0.491” vs 0.490) and -0.005” less on the exhaust (0.465” vs 0.470”) respectively. I don’t know what happens at thousands to RPM (and god know what linear velocity) to know what a maximum of 5 thou difference does at those speeds to a valve train.



But given all things equal (i.e. built heads) how does the revised profile help at the larger displacements? I did some math from an and an existing SE2 cam card I get a overlap of 43.36 degrees and an LSA of 107. Scott hasn’t commented on the cam card but states that during development they reduced the overlap to capture that intake charge. Presumably they’re shutting the exhaust earlier (just based on comparing the duration of the two cams) which would reduce the exhaust scavenging but also maximized the ram air effect will help shove more air in the cylinder.



By altering the exhaust lift and increasing it, they gain back what was lost by reducing the overlap by allowing a larger maximum port size during the exhaust stroke to help expel that exhaust gas faster.

So what does this mean for potential when you start going +30% in displacement?



His dyno profiles of the new cams show a sustained step above the SE2 across all the RPM ranges with only the slightest sign of turning over as you reach 9K redline so its pulling hard all the way through
 

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You should be very skeptical about the valve spring statement (i.e. OEM is "ok") considering the lift similarities between Jones Stg 3 (actually I think Jones recommended his springs even with his stg2) and Scott's. Take it from someone that went down this road years ago with a high lift cam, a dishonest vendor, and a very high lift cam. Cylinder 6 (and the block essentially) was toast when a spring snapped and went into the cylinder at 5000 rpm.

Lots of formulas on the web if you can figure out the installed spring height, know the oem spring pressure, etc. I have no idea what we have stock as I don't think the naturally aspirated cams are worth the bother (or money) in the Revo (save money for forced induction honestly).
I'll have to do some more research. $585 for a set of cams that deliver 10whp from 5500rpm and up would be well worth the money and time imo. Besides forced induction I don't know of much else for these bikes that delivers those kind of numbers. $585 vs $5k is a massive difference and both require somewhat extensive installations and tuning.
 

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I agree, if I’m taking the time to install higher lift cams I’m most certainly doing some head work, the least of which is upgraded springs. However (for the sake of argument) the SE2’s are advertised as drop in. Between the SE2 and the Hellraiser there’s +0.001” greater lift on the intake (0.491” vs 0.490) and -0.005” less on the exhaust (0.465” vs 0.470”) respectively. I don’t know what happens at thousands to RPM (and god know what linear velocity) to know what a maximum of 5 thou difference does at those speeds to a valve train.



But given all things equal (i.e. built heads) how does the revised profile help at the larger displacements? I did some math from an and an existing SE2 cam card I get a overlap of 43.36 degrees and an LSA of 107. Scott hasn’t commented on the cam card but states that during development they reduced the overlap to capture that intake charge. Presumably they’re shutting the exhaust earlier (just based on comparing the duration of the two cams) which would reduce the exhaust scavenging but also maximized the ram air effect will help shove more air in the cylinder.



By altering the exhaust lift and increasing it, they gain back what was lost by reducing the overlap by allowing a larger maximum port size during the exhaust stroke to help expel that exhaust gas faster.

So what does this mean for potential when you start going +30% in displacement?



His dyno profiles of the new cams show a sustained step above the SE2 across all the RPM ranges with only the slightest sign of turning over as you reach 9K redline so its pulling hard all the way through
If I'm going big bore, worked heads, etc I would just assume at that point I would need new / custom cams. I think these are more designed around stock 1250cc displacement motors with your typical, basic mods.
 

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You should be very skeptical about the valve spring statement (i.e. OEM is "ok") considering the lift similarities between Jones Stg 3 (actually I think Jones recommended his springs even with his stg2) and Scott's. Take it from someone that went down this road years ago with a high lift cam, a dishonest vendor, and a very high lift cam. Cylinder 6 (and the block essentially) was toast when a spring snapped and went into the cylinder at 5000 rpm.

Lots of formulas on the web if you can figure out the installed spring height, know the oem spring pressure, etc. I have no idea what we have stock as I don't think the naturally aspirated cams are worth the bother (or money) in the Revo (save money for forced induction honestly).
totaly agree
 

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I know of at least one 1350 bike that's lined up to get a set of Scott's cams in the next few months, so you should start to see some numbers from bikes with more work done. Once Scott starts having them in volumes, I'm tempted to swap my Jones 480/455's for a set of Scott's and see what the numbers look like.
 

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I can't see how you optimize Cam/Valve operation without upgrading the springs, but as we all know S/E Stage 2 are drop in with stock H-D dual springs, and those cams have specs close to Fitz's. so that kinda sorta disproves the immediate need for improved springs using that logic. Stock 200 # dual springs are close to coil bind at .490 lift. So are these Fitz hopefully Full Base Circle cams ? Jones springs goes to about 225 # open and the AV&V high flow valves and beehive springs are almost 275 # open ( which they recommend ) and Mike Jones says that's no problem with his tools steel cams. In any event I can see why just doing a drop in set of cams with the heads installed engine in frame yea, leave stock springs in there much less hassle, but if you're pulling the heads and/or building the engine outside the frame I think there are much better choices for springs, high flow valves and locks for long term reliability at high Rpm for whatever cams you upgrade to. Stock welded on head valves are just rude & crude. I'm sure Scott Fitzgerald has a recommendation for that.
 
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