Cam ID questions. (degree wheel 1st-timer)

[fordkiller]

Bought an engine and trying to figure out which cam is in there. I bought a Comp Cams degree wheel and have been trying to figure out the whole procedure. I used a dial indicator on the #1 piston to set TDC on the degree wheel and wire attached to the block. I noticed the You Tube "degreeing the cam" videos and most of them use the cam manufacturer's card to reference when the different intake and exhaust events occur. I don't have a cam card to reference though.

I took 2 different readings and here's what I came up with:

Got the engine at TDC and setup a dial indicator with the dial riding the outer edge of the #1 intake lifter with the cam installed. Rotated the engine clockwise and I counted 374 degrees (just over one full turn) on the dial before the dial indicator was at .050

Put the engine at TDC and counted the degrees on the degree wheel from the time the intake lifter started to rise to where it leveled-out (112 degrees) and then counted the degrees from the point where it leveled out to where it ramped down (113 degrees). I saw somewhere you can get your duration by adding the two?


Any and all help would be appreciated! I know something feels mucked-up here...

FK

 

[earlbrown]

To figure out the duration 'at .050" ' O out your dial on the base circle of the lobe, turn the crank until the dial reads .050" and note the degree reading... continue turning until it goes up and drops back down to .050". That's your 'duration at .050" '

Without knowing your cam specs you can't degree it in. But you can measure it and play with it... So that's something

 

[Chuck Leeper]

NE numbers on the end of the core??

 

[turbobitt]

Don't expect the numbers to match the cam card even if you had it......
Allan G


Posted from the TurboBuick.Com mobile app

 

[fordkiller]

Chuck, I'll get a chance later to look for can stampings.

Still confused on the duration readings. I started at TDC of #1 and did what EarlBrown said and the degree wheel spun just over 1 full turn (374 degrees) going from base circle at #1 TDC to .050" lift. Then the degree wheel went from 14 degrees (360 + 14 from earlier) to 156 degrees doing the next step (continue turning until it goes up and drops back down to .050").

So what's my duration at 0.50" then?

FK

 

[turbobitt]

Intake opening seems way late @ 14 after tdc
AG


Posted from the TurboBuick.Com mobile app

 

[Mike Licht]

Please post a picture of the degree wheel at TDC, .050 open on the intake, .050 closed on the intake, .050 open on the exhaust and .050 closed on the exhaust and we can figure it out, also measure lift on the lifter for intake and exhaust

 

[fordkiller]

Well, I figured it out finally. Someone had a Mitsubishi cam in it! (I'm kidding!)

Sounds good Mike. I'll post the pictures here later tonight.

FK

 

[fordkiller]

Pic 1 is TDC
Pic 2 is intake open at 0.50"
Pic 3 is intake closing at 0.50"
Pic 4 is exhaust open at 0.50"
Pic 5 is exhaust closing at 0.50"

Intake lift is .222" and exhaust lift is .229" lift

For the intake and exhaust closing measurements, I rotated the engine until the cam lobe ramped all the way down and then backed it off .050 and took the picture (not sure if that was right or not.

Thanks,

FK

 

[Mike Licht]

if I am looking at this correctly, I don't think those numbers / pictures are right, that would give you .344 lift with a stock rocker an about 183* intake duration and a crazy lobe sep number

 

[dr_frankenstein]

did you attain true top dead center or did you just roll the engine over until the piston was at the top and set your degree wheel?

 

[fordkiller]

I didn't use a "stop" to determine TDC. (didn't have one handy) I used a dial indicator resting on the #1 piston and took the dwell degrees (where the engine is at TDC) from the degree wheel and "halved them" so that I could get as close to TDC as possible. I've gone through about every cam manufacturer website and many web how-tos and I can't see why this is so difficult to determine at the minimum just duration. Even if I am off a few degree determining TDC, I should be able to kind of get a good estimate of what the duration is and it sounds as if either I or my cam (or both! ) are way off.

 

[Mike Licht]

you can get the duration if the TDC is off but something is not right some of your events happen at the wrong time

 

[fordkiller]

Oh well, I tried! As long as I have the engine out with the cam easy to uninstall-install I might as well get a new cam/lifters. That way I know for sure what I have and there's no guesswork involved. I used to get stuff from you way back at the Nationals in BG so I now need to find my flow sheet for my heads I had done a few years back and get my turbo and injector data and give you guys a call. I need to get a new timing cover/oil pump too.

I used to live in the Detroit area but now have a house out SW of Ann Arbor so you guys aren't too far from me. Oh one more thing, if I go with a hydraulic cam and ZDDP plus, does the cam have a good chance of lasting these days? Maybe down the road I'll get a $800 roller cam setup but it seems to me the hydraulic cams worked just fine in the 80's-90's. I realize the oil suffers now versus the older oils but I thought that the ZDDP Plus made up for those shortcomings. Or are the hydraulics cam setups still going bad from time to time even with ZDDP Plus?

Thanks for the help guys,

FK

 

[Mike Licht]

I have seen cams fail with the ZDDP and some that did not, still seems like a coin toss, even before the oil change we had cam problems. I would be more than happy to help you out either way. If you want to send me that cam I will check it here for you.
Mike