Cam degree.

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circlepilot

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I'm "degreeing" my cam. 225/6...My intake valve opening number is "dead nuts on, (with the cam card) but the closing number is several degrees early. The exhaust valve opening is several degrees early, but the closing number is dead on. My timing gear set is a Australian JP Performance double roller. The crank sprocket has multiple key-way slots for timing adjustment. Question: If two of my numbers are dead on, making any adjustment with the crank sprocket would screw those numbers up...right? It's been a while since I've done this ( only on V-8s) and never have on a /6.
Norm

Cam degree.jpg


Cam degree1.jpg
 
you are chasing your tail trying to dial by the valve opening/closings because the openings and closings are very vague. It's fine to rough check the cam grind, but you want to dial by your intake centerline.
 
you are chasing your tail trying to dial by the valve opening/closings because the openings and closings are very vague. It's fine to rough check the cam grind, but you want to dial by your intake centerline.
I'm using the instructions that came with the cam. When you specify "centerline," are you referring to the "installed center line" noted at the top of my cam card?
Norm

cam card.jpg
 
yes. have you found the correct TDC? that comes first.
you find the centerline of the cam by picking a random number, say 0.050" lift each side of peak lift(turning the crank in correct rotation direction), average the number readings on the degree wheel, that's the centerline of the #1 intake cam lobe.If it is 104, you're golden. If not you need to put in an offset key or offset bushing(whatever slants have) to correct it. Of course you'll need to recheck it.
If I have forgotten anything or directed you incorrectly, perhaps someone will chime in. I haven't dialed in a cam for about 20 yrs. Don't think I've ever done a slant.
 
I'm using the instructions that came with the cam. When you specify "centerline," are you referring to the "installed center line" noted at the top of my cam card?
Norm

View attachment 1715756339

That's not instructions, man. That just the cam card. I tried to tell you to use the intake center line method. It's much easier than whatever it is you're trying to do.

That said.....keep this in mind. If that's a Rollmaster set, remember, I had one that the crank gear was 100% marked incorrectly.

But don't concentrate on that YET. Use the intake center line method and see how it comes out.
 
That's not instructions, man. That just the cam card. I tried to tell you to use the intake center line method. It's much easier than whatever it is you're trying to do.

That said.....keep this in mind. If that's a Rollmaster set, remember, I had one that the crank gear was 100% marked incorrectly.

But don't concentrate on that YET. Use the intake center line method and see how it comes out.
yes. have you found the correct TDC? that comes first.
you find the centerline of the cam by picking a random number, say 0.050" lift each side of peak lift(turning the crank in correct rotation direction), average the number readings on the degree wheel, that's the centerline of the #1 intake cam lobe.If it is 104, you're golden. If not you need to put in an offset key or offset bushing(whatever slants have) to correct it. Of course you'll need to recheck it.
If I have forgotten anything or directed you incorrectly, perhaps someone will chime in. I haven't dialed in a cam for about 20 yrs. Don't think I've ever done a slant.

I am using the instructions you sent me, also the instructions that came from Hughes (almost the same as the ones you sent) with the Cam. "I know the "Cam Card" is just the numbers. (not instructions)!!! Regardless, If I use the ones you sent, or the ones that Hughes sent...I get the same results. Which tells me...I'm using the centerline 'method, as being described. I've checked TCD over and over. It's right. Maybe I'll make a montage of pictures or a video of this whole thing, just to get my point across that, I'm leaving something out. I even fabricated a lifter assembly (as pointed out by Hughes) in my application, by welding four (old) lifters together to insure a straight line "stable" lift indications. I can't, but get the feeling the numbers on the card are not right. There was one error already noted on the card, regarding the valve springs. The number on the card is for single springs. This cam requires double springs (which has been corrected.) I work on stuff everyday, far more complicated than this, but this is about to "get my goat!"
 
I am using the instructions you sent me, also the instructions that came from Hughes (almost the same as the ones you sent) with the Cam. "I know the "Cam Card" is just the numbers. (not instructions)!!! Regardless, If I use the ones you sent, or the ones that Hughes sent...I get the same results. Which tells me...I'm using the centerline 'method, as being described. I've checked TCD over and over. It's right. Maybe I'll make a montage of pictures or a video of this whole thing, just to get my point across that, I'm leaving something out. I even fabricated a lifter assembly (as pointed out by Hughes) in my application, by welding four (old) lifters together to insure a straight line "stable" lift indications. I can't, but get the feeling the numbers on the card are not right. There was one error already noted on the card, regarding the valve springs. The number on the card is for single springs. This cam requires double springs (which has been corrected.) I work on stuff everyday, far more complicated than this, but this is about to "get my goat!"

Now, I sent you more than one way, remember? I normally don't use the intake center line method.....and I told you that, but I also said you would probably find it easier to use the intake center line method. Did you find true TDC? That's the first step. That will tell you real quick if your gears are mis-marked. ...and find TDC using a piston stop?
 
Now, I sent you more than one way, remember? I normally don't use the intake center line method.....and I told you that, but I also said you would probably find it easier to use the intake center line method. Did you find true TDC? That's the first step. That will tell you real quick if your gears are mis-marked. ...and find TDC using a piston stop?
"Found and checked TDC several times." No I haven't been using a piston stop, but a calibrated dail indicator. I have even used the "Dutra Method" of degreeing the cam. Using the cylinder head with valves and springs installed in #2 cylinder head chamber the set on top of #1 cylinder and bolted down, this allows #6 piston to be exposed to find TDC and once found, Install the degree wheel and pointer, use a drill bit or hex wrench .010 bigger between the head and #6 piston as a stop. You then install the lifters in #1 and the push rods and rocker arms. Set the lash. No dail indicator, nothing, lift movement gets checked by lack of or of tension on the push rod. IMOP kind of crude and I didn't get the numbers required. I'll go at it again tomorrow. Maybe I'll get lucky and it will fix itself and I'll never know how it did. Happens with airplanes all of the time. :BangHead:
Norm
 
"Found and checked TDC several times." No I haven't been using a piston stop, but a calibrated dail indicator. I have even used the "Dutra Method" of degreeing the cam. Using the cylinder head with valves and springs installed in #2 cylinder head chamber the set on top of #1 cylinder and bolted down, this allows #6 piston to be exposed to find TDC and once found, Install the degree wheel and pointer, use a drill bit or hex wrench .010 bigger between the head and #6 piston as a stop. You then install the lifters in #1 and the push rods and rocker arms. Set the lash. No dail indicator, nothing, lift movement gets checked by lack of or of tension on the push rod. IMOP kind of crude and I didn't get the numbers required. I'll go at it again tomorrow. Maybe I'll get lucky and it will fix itself and I'll never know how it did. Happens with airplanes all of the time. :BangHead:
Norm

I bet that's where your difference is. The piston stop is really the most accurate way.
 
It seems to Me if Your statement is accurate, the lobes are reversed, i.e. "normal". If the exh. duration were longer than the intake as per traditional split-pattern cams, that would explain the correct O/L timing & the advanced IC & EO, opposite of the card. Do an actual lobe duration check on both lobes.
 
Could the cam have been mis-ground? Or the wrong cam card sent?
While I am on this thread I too have a question about degreeing a cam on a solid lifter engine.
I've done a couple of hydraulic liter motors few and far between. Usually I've been one of the "align the dots and forgot about it" engine builders but have been trying to check them to be sure the dots are where they are supposed to be on my last few builds. I haven't gotten into intentionally advancing or retarding cams on any of my builds.
Anyway here goes.
When degreeing a solid lifter cam, am I supposed to set the valves on zero lash/ for purposes of measuring and degreeing the cam and then loosen the lash to spec once I'm done degreeing the cam?
 
Back at it...will keep you all posted. I'm bound and determined to do this, and everyone's advice and help is more than appreciated.
Norm
 
maybe a little late for this, but I learned to do it from the "mopar books", like the Mopar Racing Manual. As I recall it was a very good explanation of how to do it and why you do it their way..
 
one more thing, make sure you're going off the correct lifter. In other words, look at the head, to confirm the order of the lifter positions. I know that seems so basic, but trying to avoid a forehead slapping moment, here, hahaha.
 
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