Okay, first I'll reiterate the data from B.W., and fill in the rest of the data for each set, which I can derive from the info that B.W. posted.
Stock AVL cams.
IVO 9*BTDC
IVC 54*ABDC
EVO 72*BBDC
EVC 18*ATDC
Intake Duration 243 degrees
Exhaust Duration 270 degrees
Intake cam centerline 112.5*ATDC
Exhaust cam centerline 117*BTDC
Lobe separation angle 114.75*
Overlap Period 27 degrees
S Cams
IVO 30*BTDC
IVC 75*ABDC
EVO 85*BBDC
EVC 50*ATDC
Intake duration 285 degrees
Exhaust duration 315 degrees
Intake lobe centerline 112.5*ATDC
Exhaust lobe centerline 107.5*BTDC
Lobe separation angle 110 degrees
Overlap period 80 degrees
S Cams (1 tooth retarded)
IVO 12*BTDC
IVC 93*ABDC
EVO 85*BBDC (Exhaust Cam not retarded)
EVC 50*ATDC "
Intake duration 285 degrees
Exhaust duration 315 degrees
Intake Centerline 130.5*ATDC
Exhaust Centerline 107.5*BTDC
Lobe Separation Angle 119*
Overlap period 62 degrees
Now, some commentary.
First, the stock AVL cams
The stock AVL cams are a relatively short duration intake cam, with a considerably longer duration exhaust cam, with a little shorter lift on the exhaust by .020"(half-mm).
They open the intake valve quite late, and close the intake relatively early, compared to earlier Bullet cams. This seems to be intended to keep the overlap period short to preserve lower rpm torque, and closing early enough to prevent much reversion up the intake. It's basically a torque cam, or profile which might be used for towing a sidecar, or band-aiding a slow port. It is not a high revving type of cam design. But it has enough to get it up to a reasonable top speed, similar to previous Bullets.
The exhaust cam reflects an attempt to work with the relatively smaller exhaust port, and the lower exhaust valve lift, to extend the exhaust stream velocity over a longer time period, so that the extraction effects might help to better scavenge the exhaust from the chamber during overlap, and help the somewhat slower intake port get moving before the piston starts going down. This is not an unusual practice. It actually is pretty well targeted for the typical Indian Bullet market in India.
The S Cams have a sportier profile, and this is the first time that I have seen specs on the S Cams. I was wondering how they were getting more results from the AVL, and now I know how. The lift isn't really different, although I still dont know if the exhaust cam lifts lower than the intake. Even so, it is clear that the S Cams have much longer duration on both intake and exhaust cam. The exhaust cam is actually in the category of racing cams in terms of duration, but not lift.
The intake cam has similar duration as the Iron Barrel cams have, and similar lift height at max. But there is a big difference in the timing and lobe center. In fact, these S Cams are remarkably similar timing to our Ace Magnum Cams, but without the added lift.
It opens the intake valve earlier than the stock AVL cams, for added overlap, which helps to extend the higher rpms, but may have some unwanted impact at lower rpm torque production. It would be generally considered in the sportier type cam overlap category. This trend continues with the later intake valve closing angle, which is much later than any of the stock Indian Bullet cams. This is also a sportier type of design, also intended to work with a higher rpm range. And the duration allows higher rpm than standard AVL cams, too. It will support higher rpm running, even without any higher lift at the valves, because it gives more time for the cylinder to get filled.
The 112.5*ATDC lobe center of the intake valve just happens to be the same as the Ace Magnum Cams.
The exhaust cam is a little too long for my taste, but it certainly is not short on duration. It will permit higher rpm running, because it gives plenty of time to get the exhaust out. It opens fairly early, so it will actually work better with higher compression than it would with lower compression. This is fine, and it also happens to be close to the same EVO timing as our Ace Magnum exhaust cam. But this long duration has a price, which turns out to be what I consider a "late" EVC timing of 50*ATDC. I think this is a little too late, and I think it will have some adverse effects on the low rpm torque. But it will support higher rpm running better. It's in the nature of the sporty cam type it is. For reference, the Ace Magnum Cams have an EVC timing of 32*ATDC.
The overlap period is pretty wide, but not too wide. It has 80 degrees of overlap, biased by 20 extra degrees on the exhaust closing side. Quite a decent overlap period for a sporty cam. It will support higher rpm running quite well, and it isn't too harmful to lower rpm torque, but there will be some effects to lower rpm torque compared to the very short overlap and short duration of the stock AVL cams.
So, in general, I think that the S Cams are a pretty sporty cam set, in terms of timing events. They fairly closely mimic the Ace Magnum Cams for timing, except for that later exhaust valve closing timing that the S Cams have. Other than that, its quite similar in timing, and the Magnum cams just primarily have more lift. I would be favorably impressed with these cams in a stock AVL or also an Iron Barrel Bullet.
The S Cams with the one-tooth retarding on the intake cam are starting to get into a timing range which I consider close(or into) the "out of bounds" area for timing in a normal engine. The 93*ABDC intake closing event is really very long, and the port that I saw in the AVL would have to rev quite high to be able to support that late of an IVC event. And at the same time, the late intake opening timing shortens the overlap period enough to likely impinge on the overlap period needed for such higher rpm running that would be necessary to work with that late of an IVC event. Lobe centers in the 130 ATDC range are not typical in regular engines. So, I think that retarding of the intake cam on this S Cam set is a little too extreme for my tastes.
The exhaust remains the same as before, since it is not retarded.
The side effects of this are that any time an intake cam closes the intake valve something like 20 degrees later than the cam that was taken out of there, there will be some compression effects. I would expect that the engine will need to go to a higher compression piston, and/or a 535 piston to take best advantage of this cam set. I realize that Bill Harris had installed this set retarded by a tooth, and his compression test didn't change much. I don't have an answer for that, but I wouldn't expect that situation to be typical. I think that was an anomaly which cannot be counted upon to happen. It shouldn't happen, given the specification change. I just can't account for it. When we do this sort of thing in the Iron Barrel, it always needs a higher compression piston to compensate for the cam timing change.
Anyway, be advised that you MIGHT likely need to use a higher compression piston and/or 535 piston to get the most out of this cam set. Obviously, it can work without that, but if the compression is brought up closer to max for the fuel being used, it can work even better. We always do it.
So, there you have it.
The S Cams are a pretty sporty cam set, IMO.
If I were using them myself, I would install them "on the dots" and do a compression test to see if I needed to increase it with the new cams. Always do a clearance check for piston-to-valve clearance, as B.W. suggests, when installing new cams, and/or increasing compression.
I would like to see them in an AVL with our port job and our hi-ratio roller rockers, pushing over .450" lift. That would be a real nice package there.