hey guys...i got a set of cams still in the towers with the lifters out...im going to get a degree wheel tomarow and was wonderinf if anyone could help me figure out how to properly check duration on these cams..they are SUPPOSE to be w41 cams..but im just wondering how EXACTLY to measure them with these tools....anyone??? ..please?!
its simple.... mount the degree wheel to the crank snout, find a near by bolt hole and bend the @!#$ out of a coat hanger and bolt i on, have it aimed at the degree wheel, you use it as the pointer for the wheel. Then take a dial indicator to the cam lobe, spin the crank when the cam lobe starts to open move it to .050 lift, then 0 the degree wheel on the pointer, continueing turning the crank intill the cam reaches its peak and starts going back down, one its .050 lift again while closing check your degree wheel.... what ever its at thats the duration on that cam lobe (do it on 1 intake and one exhaust lobe) Actual duration is measured at .050 lift, advertised duration is as soon as the any lift starts (even though its not actually flowing alot of manufactures tell you the advertised duration not the actual to make the cam seem bigger then it really is.
btw its late I can't hink long day..... the lift you measure from is 50 thousands, not sure if I typed that right (.050)
off of the engine? I would think a dial indicator would work.
Here, a quote from Quad4forums for ya.
Quote:
My answer is based on my work profiling several sets of cams:
a. LO (only cams with 0.370" lift; all others listed hereafter are 0.410" lift (can be measured easily with calipers -- or even eyeballed side-by-side))
b. HO (212 degree duration)
c. W41 (219 degree duration)
d. "W41 #2"?? (226 degree duration)
To do it, I drilled a small hole in a (spare) set of cam covers (although I could pipe-plug the holes if I wanted), and used a special dial indicator probe (OK, OK... just a piece of AL welding rod!) which shot past the cam and hit the top of the lifter, then I used a degree wheel on the crankshaft and assembled the timing chain. Or if you wanted, put a degree wheel just on the cam and multiply all angles by 2. (360 cam degrees = 720 crank degrees)
(the duration numbers are quoted at 0.050" lift -- duration (in crank degrees) that the lobe is higher than the 0.050".)
Josh W41 #1 are .410" and 226*
The W41 #2 are .430" and 224* - That's what I have in my 12:1 quad
Gilles
2.3 Ho
