4-pattern cam?
#1534735
11/18/13 02:35 PM
11/18/13 02:35 PM
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Joined: Jul 2005
Posts: 636
Graz, Austria
DGS
OP
mopar
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OP
mopar
Joined: Jul 2005
Posts: 636
Graz, Austria
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I just read the following article about Comp's 4-pattern cams: http://www.chevyhardcore.com/tech-storie...car-technology/Although the article is about Chevys the same principle should work for Mopars: in order to compensate for the different intake runner lengths of the outboard and inboard runners Comp Camps uses 4 different lobe patterns. Here's a pic for clarification  Are there any Mopar cams like these? Would a custom cam grinder be able to make a 4-pattern cam? I wonder if the difference in power/rpms would be worth it...
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Re: 4-pattern cam?
[Re: DGS]
#1534736
11/18/13 02:46 PM
11/18/13 02:46 PM
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Joined: Jun 2006
Posts: 5,163
CT
GTX MATT
master
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master
Joined: Jun 2006
Posts: 5,163
CT
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My opinion: 1. This is the wrong way to fix the problem, to correct this one should be in the market for an intake with equal length runners. 2. What about the headers? If you're running unequal length headers, and each is different, and each intake runner length is different, there should be 16 optimized lobes, no? 3. Its a gimmick. For you to realize a power gain you would need to optimize your cam for each runner, head port (remember they don't all flow exactly the same), and header primary tube length. The Nascar teams spend plenty of time R/Ding their engines to know what is optimal, they can get use out of a cam with different lobes. A street car, with a cam people are going to buy off the shelf, that is probably already not just not optimal but possibly completely wrong for their app? I don't think its going to make much difference.  And what are we talking for differences lobe to lobe? 2 degrees of duration? Different LSAs? Lift?
Last edited by GTX MATT; 11/18/13 02:49 PM.
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Re: 4-pattern cam?
[Re: DGS]
#1534737
11/18/13 06:24 PM
11/18/13 06:24 PM
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Joined: Nov 2003
Posts: 3,060
Western New York
sixpackbee
master
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master
Joined: Nov 2003
Posts: 3,060
Western New York
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If you took it to the nth degree you could have 16 different lobes.
Last edited by sixpackbee; 11/18/13 06:37 PM.
1959 Bugeye Sprite
1967 Charger Black L code
1967 Coronet R/T Convert Green 440 auto bought from original owner
1968 Charger R/T Bronze 440 4 spd console AM/FM
1969 Super Bee WM21H B5 A40 D21 N96
1969 Barracuda Formula S 340 Convert pilot car
1969 Hemi Road Runner RM23J D32 Omaha orange 4.10 Dana N96 N85
1970 Super Bee WM23N FE5 V1X 3.91 axle package, N96
1970 Road Runner RM21N B3 V1X D13
1971 MG Midget
1971 Road Runner RM23H GW3, A57
1972 Road Runner RM23P FY1, D21
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Re: 4-pattern cam?
[Re: rowin4]
#1534739
11/18/13 06:41 PM
11/18/13 06:41 PM
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Joined: Nov 2003
Posts: 3,060
Western New York
sixpackbee
master
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master
Joined: Nov 2003
Posts: 3,060
Western New York
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This kind of thing is filtering down from Cup stuff pretty much. When every gram of power is precious things get this anal.
1959 Bugeye Sprite
1967 Charger Black L code
1967 Coronet R/T Convert Green 440 auto bought from original owner
1968 Charger R/T Bronze 440 4 spd console AM/FM
1969 Super Bee WM21H B5 A40 D21 N96
1969 Barracuda Formula S 340 Convert pilot car
1969 Hemi Road Runner RM23J D32 Omaha orange 4.10 Dana N96 N85
1970 Super Bee WM23N FE5 V1X 3.91 axle package, N96
1970 Road Runner RM21N B3 V1X D13
1971 MG Midget
1971 Road Runner RM23H GW3, A57
1972 Road Runner RM23P FY1, D21
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Re: 4-pattern cam?
[Re: DGS]
#1534740
11/18/13 06:46 PM
11/18/13 06:46 PM
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Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
BradH
Taking time off to work on my car
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Taking time off to work on my car
Joined: Jan 2003
Posts: 15,439
Val-haul-ass... eventually
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There was a somewhat heated thread on SpeedTalk about the whole 4-pattern cam deal. Some claimed it was leading-edge technology, while others screamed "Gimmick!" and said that stuff had been tried and dropped years ago by NASCAR engine builders.  What I recall from reading some article (possibly the same one) that did a comparison was IMO it wasn't really an apples-to-apples cam comparison. I looked at where the gains from the 4-pattern deal were vs. the other cam used as the baseline and thought if they'd simply tightened up the baseline cam's LSA a couple of degrees it would have shown similar improvements, too. Interesting reading, but nothing that's going to get me all hot and bothered to buy one.
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Re: 4-pattern cam?
[Re: BradH]
#1534741
11/18/13 06:52 PM
11/18/13 06:52 PM
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Joined: Jun 2006
Posts: 5,163
CT
GTX MATT
master
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master
Joined: Jun 2006
Posts: 5,163
CT
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Quote:
There was a somewhat heated thread on SpeedTalk about the whole 4-pattern cam deal. Some claimed it was leading-edge technology, while others screamed "Gimmick!" and said that stuff had been tried and dropped years ago by NASCAR engine builders.
What I recall from reading some article (possibly the same one) that did a comparison was IMO it wasn't really an apples-to-apples cam comparison. I looked at where the gains from the 4-pattern deal were vs. the other cam used as the baseline and thought if they'd simply tightened up the baseline cam's LSA a couple of degrees it would have shown similar improvements, too.
Interesting reading, but nothing that's going to get me all hot and bothered to by one.
I think it could be debated heavily because it can work, but for them to be selling these to your average hobbyist is a gimmick. Not bashing Comp at all by calling it a gimmick, they're just trying to get more of the marketshare when the market is FLOODED with cam options.
I think it will always be an apples to oranges comparison unless you are certain that you've already got THE optimal dual pattern cam in the engine already, and it is then changed to a four pattern cam.
If it were the four most optimal lobes for an engine, sure it would make more power. But again, it is highly unlikely that you will have the optimal four lobes. The key work is optimal.
Now I need to pin those needles, got to feel that heat
Hear my motor screamin while I'm tearin up the street
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Re: 4-pattern cam?
[Re: GTX MATT]
#1534742
11/18/13 11:59 PM
11/18/13 11:59 PM
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Joined: Jul 2013
Posts: 561
USA
B3RE
mopar
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mopar
Joined: Jul 2013
Posts: 561
USA
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Quote:
Quote:
There was a somewhat heated thread on SpeedTalk about the whole 4-pattern cam deal. Some claimed it was leading-edge technology, while others screamed "Gimmick!" and said that stuff had been tried and dropped years ago by NASCAR engine builders.
What I recall from reading some article (possibly the same one) that did a comparison was IMO it wasn't really an apples-to-apples cam comparison. I looked at where the gains from the 4-pattern deal were vs. the other cam used as the baseline and thought if they'd simply tightened up the baseline cam's LSA a couple of degrees it would have shown similar improvements, too.
Interesting reading, but nothing that's going to get me all hot and bothered to by one.
I think it could be debated heavily because it can work, but for them to be selling these to your average hobbyist is a gimmick. Not bashing Comp at all by calling it a gimmick, they're just trying to get more of the marketshare when the market is FLOODED with cam options.
I think it will always be an apples to oranges comparison unless you are certain that you've already got THE optimal dual pattern cam in the engine already, and it is then changed to a four pattern cam.
If it were the four most optimal lobes for an engine, sure it would make more power. But again, it is highly unlikely that you will have the optimal four lobes. The key work is optimal.
I read a little on this some time ago. The reasoning behind the concept is that classes restricted to a single carb manifold can not have all the runners equal and will require different timing events to optimize each cylinder. It doesn't mean anything on tunnel rams with dual carbs where the runner lengths are equal and the throttle bores are positioned directly above the runners as they, theoretically, will all flow the same and have the same velocity.
Comp should be able to put those types of lobes on any shaft since the chevy ones are custom grinds, too, as far as I know.
Mike Beachel
I didn't write the rules of math nor create the laws of physics, I am just bound by them.
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Re: 4-pattern cam?
[Re: B3RE]
#1534743
11/19/13 09:04 PM
11/19/13 09:04 PM
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Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
HotRodDave
I Live Here
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I Live Here
Joined: Jan 2005
Posts: 12,419
Kalispell Mt.
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With 4 different lifts how could you ever get your rocker geometry correct with a shaft? Do you just take an average lift and use that?
I am not causing global warming, I am just trying to hold off a impending Ice Age!
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