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The R286/500-4 was commonly used in the Super Stock Hemis in the late 70's and maybe early 80's. The R290/446-4 was the first popular Crane grind for the Pro Stock-style Hemis, but was a killer on valve springs. It was replaced by the R296/4778-8 which wasn't quite so hard on springs even with more lift. I have never heard of the R285/410-8 but suspect it was for the heavier Super Stock cars.

Mark

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Your right...the R290 was the first really big cam used in early HEMI pro/stockers and it found it's way over to super/stock.
I've been using that cam for about 30 years and still love it..
My newest HEMI stroker(478) is using it and the motor will be going in my "SILVER BULLIT" clone.

The cam specs very from make to make. So the cam card showing it over 700lift is wrong for a HEMI. Get an early('71-'74) Crane Cams catalog!
Fred

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So the cam card showing it over 700lift is wrong for a HEMI. Get an early('71-'74) Crane Cams catalog!
Fred

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The " Basic " Crane grind number system would be :

R-288/4714-2S-10

The Prefix would indicate the type of lifter.(in this example R )
H = hyd flat tappet
S = Solid flat tappet
R = Roller Tappet
HR = Hyd Roller
IR = Inverted Ramp Mechanical Roller
TR = Track Mechanical Roller
ect ect

The second grouping is the duration @ .050.( in this example 288 )

The 3rd is the INTAKE lobe lift.( In this example .4714 )

The - 2 after the intake lobe lift would mean the ex is 10 deg longer dur @ .050.

-2S , 2S1 , 2S2 indicated more Ex duration but not exactly 10 deg more.

-2R would mean 10 deg less exhaust dur.

-2SR means less Ex dur but not exactly 10 deg.

The last set of numbers is the LSA when you add 100 deg to it.( in this case the 10 plus 100 = 110 LSA.
Have no idea what the S stood for. Maybe the S meant Special,

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Well that would mean this cam could possibly have a 104 LSA not a 114? LOL....My brain hurts now