cam degreeing

I have been trying to degree a cam all morning,card wants 112 centerline,best i can do is 111 or 114 using kb geardrive.Thinking about using 114,how much does 3 degrees effect blown bbc? thanks

 

I degree the cam to where the cam card says the intake valve opens (@.050 lift), for example mine would be degreed at 35 degrees BTDC. I thought the centerline of a cam was pre-determined, never used it for setting the cam up.

 

cam

111 is close enough at that point you are splitting hairs good luck

 

Decreeing a cam is like baking a cake,to much sugar it tastes like shit, to little sugar it taste like shit, do it right, it dose make a difference, and do it like Ken Sitko dose, thats the best way.

 

With the 111 do a plastercine (modelling clay) check on no. 1 and on the 1st cylinder of the split of your firing order. compare to see if they are even and you have enough piston to valve clearance on both.

Then set it up at 114 and do the same thing.

Personally I would go with the 111, the 114 will give you a very slight retard, good for the top end but so little you prob wouldn't notice.

 

+1. I check open and close of the intake/exhaust valve to make sure the cam was cut right (on the first cylinder anyhow), then throw it in on the intake closing @ .050.

 

Lobe Seperation is pre-determined.

Intake Centerline, commonly referred to as "centerline", is the relationship from piston TDC to cam lobe max lift in degrees. So this is variable depending on how you install the cam.

 

So if you were to degree your camshaft in "straight up" you'd be setting the centerline to whatever the lobe separation angle is, correct?

 

It is hard to find the centerline on many modern cams with asymetrical lobes. When the cam company gives a .050 number, they have done the figuring for you.

 

The problem is the bbc part...lol

 

Intake Closeing!

 

That is Correct

 

Centerline is just for checking to make sure the cam was ground correctly. Install it by the degree BTDC @.050.

 

degreeing

how could this be done without any numbers? does in .050 43btdc full lift 100 atdc.
ex .050 83 atdc full lift 130 btdc, do these figures sound right, 426 hemi, i have been struggling all day, this is on no 1 cyl, would these figures be the same on any other cylinder takinginto account tdc each cyl

 

Thanks Eli, I think. I have to modify the procedure though, due to recent bad experiences. From now on I am going to check the cam timing after all the push rods are in place, just to make sure all the backlash is taken up and I am not 2, 3 or 4 degrees behind my target. Ran four weekends with the cam retarded, is running much better now.

 

It helps to have the right cam timing tool, also.

 

numbers

Give us all of the numbers from your card.

The center line method is by the most consistent. Some will disagree but only because takes time.

With your numbers it will give us a starting point. (numbers @ .050

Noel