Edelbrock and Summit cams are made by...

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Crane.
I’m pretty confident that they’re Crane lobes, but they could be machined about anywhere
of course. Crane makes lots of private label cams, including the Ford
Motorsport and Mopar Performance cams. The lobe design just looks too much like Crane’s HP series,
which is the most gentle profile they offer. These are
equivalent to factory style lobes, except with more lift and duration.

Here’s
the two Edelbrock cams and the HP lobes used:
   Edelbrock 2132: 278/288, 204/214@0.050,
0.448/0.472 lift, uses lobes HP-204/2800 and HP-214/2947  
   Edelbrock 7132: 310/320, 234/244@0.050,
0.520/0.544 lift, uses lobes HP-234/3254 and HP-244/3400

And
a similar combination of HP lobes are used to make the two Summit cams:

    Summit K8600: 289/300, 214/224@0.050,
0.473/0.497 lift, uses lobes HP-214/2947 and HP-224/3100

    Summit K8601: 300/304, 224/234@0.050,
0.497/0.521 lift, uses lobes HP-224/3100 and HP-224/3254

The
ramps on these among the slower of available off the shelf hydraulic cams,
with a Hydraulic Intensity of about 56, depending on the lobe. That’s the amount
of degrees it takes to get from 0.004” to 0.050” plus the degrees from
0.050” to 0.004” on the closing ramp, so lower numbers mean faster ramps. Slow
ramps cost power, but are quieter and last longer. Here’s a range of Hydraulic
Intensity data of other cam profiles offered for AMC: 

   Isky Supercams use HI = 61

   Crane HMV cams use a HI = 56

   Comp High Energy cams use HI = 51.6

   Comp Xtreme Energy use HI = 45.8 (intake)

The
overall lobe agressiveness for the HP profile is about average for a 0.842
lifter profile. For me the best indicator of this is to look at the intensity
from 0.050” to 0.200” in degrees, and for these lobes that number runs around
91. Just like Hydraulic Intensity, a lower number indicates a more aggressive lobe
because less duration is required to achieve a given amount of lift. Some
comparison points:

   Isky Supercams use 95 degrees

   Comp High Energy cams use about 95 degrees

   Crane HMV cams use 89 degrees

   Comp Xtreme Energy use about 87.5 degrees
(intake)

   Crane H3 lobes use about 84 degrees, and are
0.904” lifter specific

   Comp XE4X4 lobes use about 83 degrees, and
again are 0.904” lifter specific

With
the reasonably slow ramps and average lobe aggressiveness these should run pretty quiet and
last a long time, and should be much less prone to eating up lifters than say a
Comp cam would. If you’ve got an engine block that has struggled with lifter
issues possible due to lifter bore wear etc, these cams might be a good choice.
But if you’re looking for higher performance levels, there are better choices
out there.

Edited by Greyhounds_AMX - Apr/29/2016 at 7:44pm