273 Cam identification

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Jarmo72

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Hello, can someone give me an idea of paint marks. Is there some duration and valve lift information behind those colours?
WP_20161007_08_45_57_Pro.jpg

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Paint marks have no meaning that I know of..........if these are factory cams, 2 V-blocks and a dial indicator on a stand would give you the best/quickest identification.........lobe lift times rocker arm ratio equals valve lift, factory rocker ratio is 1.5.

1964 to 1967 273 2bbl valve lift: .395 intake, .405 exhaust, 240 degrees seat duration "I" and "E"
1965 to 1967 273 4bbl valve lift: .415 intake, .425 exhaust, 248 degrees seat duration "I" and "E"
1968 to 1969 273 all, valve lift: .373intake, .400 exhaust, 240 degrees seat duration "I", and 248 degrees seat duration "E"

Hope this helps.
 
Jarmo...are those factory cams...they look brand new. If they're aftermarket, they will have numbers stamped into one end of the shaft for identification.
 
I took out that cam about year ago, couldn't find any marks on that. It performed fine, but it was worn out, I decided to go reconditioning route.
Now I have that Cam on my garages table and Comp Cam mounted.
Workshop, who maid repair, informed that it has .406 lift both I and E. Duration is 201 both I and E.
I am just curious can it be so? I have also asked the meaning of those paint stripes ( from the repair workshop) but haven't got the reply yet.
Anyway solid lifters and a above shown Cam performed better than the Comp Cam 20-221-3 with hydr.lifters. I could get max rpm on shorter time. I am happy on my 242Hp's and 263 torque, but some day I will but that Cam back under the hood. Combination is standard 273 with 4 bbl.
 
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Paint marks have no meaning that I know of..........if these are factory cams, 2 V-blocks and a dial indicator on a stand would give you the best/quickest identification.........lobe lift times rocker arm ratio equals valve lift, factory rocker ratio is 1.5.

1964 to 1967 273 2bbl valve lift: .395 intake, .405 exhaust, 240 degrees seat duration "I" and "E"
1965 to 1967 273 4bbl valve lift: .415 intake, .425 exhaust, 248 degrees seat duration "I" and "E"
1968 to 1969 273 all, valve lift: .373intake, .400 exhaust, 240 degrees seat duration "I", and 248 degrees seat duration "E"

Hope this helps.
And the 68 and 69 cams were hydraulic originally.
 
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