Camshaft selection?

Old 03-01-2014, 09:01 AM
  #11  
zipper06
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Last year i did some rockwell testing on 3 different cams, one older solid flat tappet Bullit with more than 100 passes on it (still good) it checked 45/47 on the RC scale, i checked a failed hydraulic comp cam newer and it checked 39/41 on the RC scale, i also checked a comp cam solid roller, it checked 58/59 on the RC scale, I also checked solid and hydraulic flat tappet lifter, theu all checked 58 on the RC scale on the bodies. I also checked solid roller lifters on the body and they checked 43 on the RC scale. I have in the shop a certified Rockwell tester where i work.
All the flat tappet cams are failing from most of the mfg'er and they blame it on the lifters, that's just not so, it their HT method and the fact that they used to nitride the cams but now they are cutting cost and won't gurantee anything, they just set back and say O'well. I think the big push is to go hydraulic roller stuff because they make a ton of money on them.
I used to run Compcam roller cams but i no longer do, but stil have a couple laying around,
I personally run Bullit cams and that's what i use on engine builds, they have been good to me and for me.

JMO

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Old 03-01-2014, 11:46 AM
  #12  
ajk
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Zip, clue me in a little further if you don't mind on the Rockwell testing. Is there standard # that these are compared off? I see 45/47 and 39/41 etc. I don't want to sound as dumb as I am but what does that indicate? Thanks Al
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Old 03-01-2014, 12:51 PM
  #13  
zipper06
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Originally Posted by ajk
Zip, clue me in a little further if you don't mind on the Rockwell testing. Is there standard # that these are compared off? I see 45/47 and 39/41 etc. I don't want to sound as dumb as I am but what does that indicate? Thanks Al
The lower the number the softer the metal, so the newer cam was 7 points softer than the older cam. The older cam i tested was about 11 or 12 yrs. old and the newer cam was 4 yrs. old and had 4 flat lobes on it.
I had run the older flat tappet cam in my 406" motor with 135 lbs of spring rate. The newer one cam out of my El Camino, with 115 lbs of spring rate with about 3,000 miles on it.
The only compaeison was that todays cams are not heat treated as good as the older cams were, and maybe not even as good of cast iron.

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Old 03-01-2014, 06:52 PM
  #14  
Swiley383
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Probably Chinese made cores would be my guess cheaper overhead and less quality. Seems way to common these days. Made in the USA with Chinese steel.
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Old 03-06-2014, 11:05 PM
  #15  
letreat
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Since you're having a converter built I wouldn't worry about any POS dual plane or anything like that. A 383 in that truck leaving the line at 6 or 6500 would be a must IMO. I'd run mid 250's on the intake and low 260's on the exhaust at .050 on a 107 or 9 LSA. Put a super vic on that dude and rev r up where she'll run.
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Old 03-07-2014, 02:03 AM
  #16  
RogueDog327
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Originally Posted by letreat
Since you're having a converter built I wouldn't worry about any POS dual plane or anything like that. A 383 in that truck leaving the line at 6 or 6500 would be a must IMO. I'd run mid 250's on the intake and low 260's on the exhaust at .050 on a 107 or 9 LSA. Put a super vic on that dude and rev r up where she'll run.
Yea I would stick to the "pos dual plane"

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