Camshaft Design Question/S.A.E. Question


http://209.208.111.198/Topic23407.aspx 		Print Topic | Close Window

By Oldmics - 16 Years Ago
Can anybody provide me with the angle of the "Y" block lifter bores?

Can someone tell me what the S.A.E. measurement spec was used for camshafts in 1956?  I believe its .006.

Oldmics

By pegleg - 16 Years Ago
The advertised specs on my blower cam are different from intake to exhaust. What do mean angle?
By Oldmics - 16 Years Ago
The angle of the lifter bores in the block casting.

Oldmics

By Duck - 16 Years Ago
Wouldn't they be 45 degrees either side of the zero (straight up and down) line ?
By Don Woodruff - 16 Years Ago
I do not recall the angle but it is not 45 degrees(parallel to cylinder bores). I had a camshaft design manual at one time that laid all of this out but I cannot recall the exact angle. It would be possible to measure it by inserting rounds into the tappet bores making a couple of measurements and a little trig or just laying it out on a sheet of paper. A good automotive machinist should have access to this number. I do not recall it the angle varies from engine designer to engine designer. 
By ejstith - 16 Years Ago
Just curious I guess, but why would somebody want to know this?
By pegleg - 16 Years Ago
I see what he means. Ther cam is further away from the bore centerline than the rocker arm contact point, so the lifter bore is angled out to compensate. The included angle must be greater than 90 degrees. I do not have a clue what it would be, although it would be simple to calculate, but difficult to measure accurately on the casting.
By mctim64 - 16 Years Ago
I retract my last statement, it looks like the lifter bores are parallel with the cylinders after all.
By Oldmics - 16 Years Ago
ejstith (3/12/2009)
Just curious I guess, but why would somebody want to know this?

Has to do with calculating the valve event timing.

Oldmics

By Ted - 16 Years Ago
Oldmics (3/10/2009)
Can someone tell me what the S.A.E. measurement spec was used for camshafts in 1956?  I believe its .006.

1956  B6AE-6250-B  camshaft specs are:

Intake tappet lift (opens) BTDC 12° @ 0.016”

Intake tappet lift (closes) ABDC 54° @ 0.019”

Exhaust tappet lift (opens) BBDC 58° @ 0.015”

Exhaust tappet lift (closes) ATDC 8° @ 0.018”

Oldmics (3/10/2009)
Can anybody provide me with the angle of the "Y" block lifter bores?

I don’t have a clue as to the angle the lifters actually reside in the Y block itself but as Frank mentions, the measurements could be reverse engineering from some blocks.  Dennis K. would be in the best position to answer this as he did have access to the original Ford Y blueprints.

ejstith (3/10/2009)
Just curious I guess, but why would somebody want to know this?

If checking the valve events on all eight cylinders and you find variability in a left-right bank correlation, then either the lifter angle or the camshaft bore being off center are great places to start looking for the problem.  This is another reason to always check the #1 and #6 cylinders when degreeing in a camshaft at the very minimum as this will point you towards other areas besides the camshaft itself in finding a problem with valve event timing.

By pegleg - 16 Years Ago
I would also imagine the cam grinders would have that information. They would need it to accurately develope the lobe centers on the cam.
By Oldmics - 16 Years Ago
Ted

Thanks for the info-Not what I anticipated.

I do have access to the lifter angle and will post it up.

Oldmics