[Disesl]

Hi im building a 4040 big inc SBC. the block is a worldproducts motown. A friend gave me two new cams Edelbrock #2201 & crower #00426 both cam are roller. My Question how far are the valves open at T.D.C. with the cam at split-overlap position. I talk to a summit tech he said call the company's. So i call & call & email & email no luck. This information will make it easy to check my v/p clearance. SOME HELP will shure be welcome....

[68NovaSS]

Edelbrock 2201 - Camshaft, Hydraulic Roller Tappet, Advertised Duration 296/300, Lift .539/.548

Crower - Adv duration 288/290 Lift: .570/.584

Also changed the title of your post.

[Disesl]

oookkk..

[Disesl]

I was looking to buy a Isky cam thay have all the overlap spece for there cams. so that you can know if the cam will work befor you buy it

[68NovaSS]

Every cam manufacturer should have that information readily available online

[techinspector1]

Originally Posted by Disesl

My Question how far are the valves open at T.D.C. with the cam at split-overlap position.

There is no way to answer your question unless you know the amount of lift per degree of crank rotation as the intake is opening and the exhaust is closing, something only the manufacturer knows and does not tell the consumer. You might use the figure of 0.007" lift per degree, but that will only get you close, it will not be exact.

You should also know that piston to valve clearance is not a mathematical function, it is a mechanical function. Each and every motor must be checked with either the "clay on the piston crown" method or with a dial indicator and soft spring arrangement. There are simply too many variables to be able to sit down with pencil and paper and figure it out. For instance, not every valve seat will be the same distance from the block deck because of its position in the cylinder head, gasket thicknesses vary, piston deck heights vary, rocker arm ratios vary, etc., etc.