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Camshaft Lobe Width?

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Post Options Post Options   Thanks (1) Thanks(1)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Topic: Camshaft Lobe Width?
    Posted: Feb/11/2019 at 7:23pm
So just bought and returned a Comp Cam camshaft. It had lobes anywhere from 0.0406" to 0.460" wide.
I have 2x original AMC camshafts and they are both 0.500" to 0.508" lobe widths. In fact I remember all being at or near 0.500" lobe width.
Bought Comp before with 0.485" + lobe width.
Who sells AMC camshafts with factory spec lobe widths? I have not found it in a search, and the manufacturers don't seem to advertise it.
Duration, lift, separation ... are second priority to me as far as an engine build. 
Not a straight out performance builder, street power and longevity. Won't use aluminum roller rockers as their fatigue life cycle is 30,000 to 40,000 miles - 100,000 miles is the goal. 
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Post Options Post Options   Thanks (1) Thanks(1)   Quote MattsGarage Quote  Post ReplyReply Direct Link To This Post Posted: Feb/11/2019 at 8:54pm
I have a howards hydraulic flat tappet here. Measures .503 to .509. I just put a howards solid flat tappet in the new engine, and it degreed in near perfect.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Feb/12/2019 at 6:50am
Thanks, Howard's it is.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote MattsGarage Quote  Post ReplyReply Direct Link To This Post Posted: Feb/12/2019 at 7:03am
Another thing to note on howards, their lifters are the correct diameter.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Greyhounds_AMX Quote  Post ReplyReply Direct Link To This Post Posted: Feb/12/2019 at 5:11pm
This is really interesting. 

I wonder how wide Bullet lobes are.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Feb/12/2019 at 6:15pm
Yes it is. Took a 360 apart a few years ago with an aftermarket cam with 0.430" lobes. The lifters and cam were shot. Cam was working the edge (rounding) into some of the lifters. 0.055" and the cam would have been near the lifter edge and likely everything would have been good.
On the pressure side of things, after many miles the cam/lifter contact area of the old AMC cams was about 0.250" and the top of the lobe 95% to 100%.
I would assume the less surface area you have the higher the pressure, at least that is the math I learned.
I believe AMC knew what they were doing when they designed the lobe width.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote imacarfan2 Quote  Post ReplyReply Direct Link To This Post Posted: Feb/17/2019 at 5:23pm
I just measured two cams for their lobe with. I only did one or two lobes on each and will check them all later. The cams were both older cams; one an Edelbrock Performer and the other the small Summit cam (K8600). All the lobes I measured were a hair over .500, maybe 17/32nds which is about .531, but maybe not even that much. My measuring device is in sad shape, so readings should be taken with a grain of salt. They are definitely over .500, though.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote a401classic Quote  Post ReplyReply Direct Link To This Post Posted: Feb/18/2019 at 2:51pm
My Comp Cams custom hydraulic roller cam has 0.570" wide lobes, wider at the base circle.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Trader Quote  Post ReplyReply Direct Link To This Post Posted: Feb/25/2019 at 11:19am
So, looking at the Howard's cams and doing a little playing.
The 310021-14, 277 duration, intake and exhaust; 0.480" lift - fine for bridge rockers; 223 @ 0.050, not overly aggressive lift - fine for bridge rockers.
114 LS and 110 ISL.
This is tame, but advancing this to 106 ISL puts dynamic compression at 7.9:1 on a 401 with the Wiseco 9.5:1 forged pistons, by my calculations.
This looks more appealing of the Howard's product line for street use, pump gas (93) and standard transmission.

Expert thoughts? Are my calculations close?

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Post Options Post Options   Thanks (0) Thanks(0)   Quote MattsGarage Quote  Post ReplyReply Direct Link To This Post Posted: Feb/26/2019 at 9:48pm
Have you ever heard of Mike Jones? He has an online cam recommendation form at Jones racing cams. The response you get is directly from him. And there's a spot to put comments also as for your durability concerns. It asks for a lot of info but imo it's well worth the time as he is really good at what he does. 
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