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Cam Specs

CWR

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I am not a mechanic by any means......can anyone tell me what this means......just received from previous owner
 

Hoosier Bird

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That would be your Cam Spec card. Needed to degree in a cam if needed. I would hang on to it but most people don't have one. Not a big deal to come up with if you know what cam you have........ :thumbsup: If this doesn't answer your question let me know.
 

CWR

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I don't know what cam I have.Its difficult to get the info coming from California
 

mcmopar

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Here is what you have: Its a mild cam - not quite as big as the stock HP cam, actually.
Duration at 0.50" valve lift is 208 degrees on the intake and 214 degrees on the exhaust.
Advertised Duration is 262 degrees intake and 270 degrees exhaust.
Valve lift w/stock rockers is .420" intake and .440" exhaust.
Overlap looks to be 42 degrees (the amount of time the intake and exhaust valves are open on the intake stroke).
Valve spring pressures are rated at 280-300 psi seat pressure when the valves are open and 100-120 psi seat pressure when the valves are closed.

The stock "road runner" cam is a bit larger. Specs are:
Duration @ .050" lift: 228 degrees intake / 241 degrees exhaust
Advertised Duration: 268 degrees intake / 284 degrees exhaust
Valve lift with stock rockers: 0.450" intake and 0.458" exhaust
Overlap is 46 degrees.

The cam you have is a nice "cruiser" cam that should deliver reasonable fuel economy and a smooth idle. It is similar to the stock '69 275 hp 2bbl cam (300 +/- hp with a 4 bbl carb)
 

Hoosier Bird

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I see mcmopar replied but after taking the time to type this I'm sending it anyway.
If this card is your cam then you have a 262-70H grind cam and 1.5 ratio rockers. Basically that tells you that you have a cam that the intake valve remains open for 262 degrees of rotation. Exhaust remains open for 270 degrees. The cam lift is how much the cam would lift without the rockers. The rockers are a 1.5 ratio which means when the cam lift it from 1 side the other side actually move 1 1/2 times as much. The recommended spring pressures at the bottom are talking about when the valve is open to max lift they want it to have 280-300 pounds of pressure and when it's closed they want it to have 100-120 pounds of pressure. Let me know if this helps or not......... :D
 

mcmopar

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:thumbsup:
Cam lift x rocker arm ratio = valve lift.
The original stamped rocker arms were not all that accurate when it came to ratio. They varied anywhere from 1.4 to 1.5 so your valve lift will vary accordingly, according to how accurate each rocker arm was manufactured. This is partly the reason some engines ran better than others but there were other factors involved as well.
 

george68hemirr

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I didnt see anything about degreeing the cam....i see the valve lash is set at 0.00...but lets say it was degreed at 6 degrees before TDC...does he set his valve lash at 6 degrees before TDC or at TDC???
 

mcmopar

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In the upper right side of the card it says to degree the intake lobe to 110 degrees. I really would not worry about degreeing it in since it is in the car and running, unless it is running badly. The mechanic probably just aligned the timing marks on the cam and crank sprockets. And the valve lash is non-adjustable if he is running stock rocker arms.
 
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