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cam degreeing confusion #1198006 03/16/12 04:30 PM 03/16/12 04:30 PM
Joined: Dec 2004 Posts: 118 South Jersey JerseyJoe OP member
JerseyJoe OP member Joined: Dec 2004 Posts: 118 South Jersey	I'm using intake centerline method, when measuring at .050 valve lift does my dial need to be on the lifter or can it be on the valve retainer(factoring in my 1.5 ratio rockers)? I keep coming up with the same TDC but @ .050 (dial on the valve retainer) I'm not getting anywhere near the 106 centerline on the cam card. Any help is appreciated, Joe

Re: cam degreeing confusion [Re: JerseyJoe] #1198007 03/16/12 05:51 PM 03/16/12 05:51 PM
Joined: May 2011 Posts: 4,489 northern,Ohio,USA C Clanton master
Clanton master C Joined: May 2011 Posts: 4,489 northern,Ohio,USA	it would be good to measure both ways lifter/retainer and the lifter method would show the most accurate/true cam and you would adjust the retainer reading to match the ICL you want with the crank gear. GOTBOOST!New improved with Victor heads. http://www.enginelabs.com/mopar-big-bloc...t-of-necessity/

Re: cam degreeing confusion [Re: JerseyJoe] #1198008 03/16/12 06:17 PM 03/16/12 06:17 PM
Joined: Aug 2003 Posts: 43,129 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,129 Bend,OR USA	Quote: I'm using intake centerline method, when measuring at .050 valve lift does my dial need to be on the lifter or can it be on the valve retainer(factoring in my 1.5 ratio rockers)? I keep coming up with the same TDC but @ .050 (dial on the valve retainer) I'm not getting anywhere near the 106 centerline on the cam card. Any help is appreciated, Joe checking the LSA can be done on the lifter or the retainer, checking the CAM SPECS. can ONLY be done on the lifter as that is what the cam grinder bases their specs on, cam lift at the liter, not at the retainer I like to do the LSA at the retainer as the motor knows what the valves are doing, it doesn't know what the lifter is doing The rocker ratio will make all the cam specs. read at the retainer wrong be the amount of the ratio, IE 1.5 ratio will have more lift and duration at the retainers than at the lifters, a 1.8 ratio will have even more BTW, I like to check the LSA on the exhaust sides to verify that the intake side and the exhaust sides are truly ground like the cam card calls for, IE if straight up on a 110 LSA both lobes should be in at 110, if advanced two degrees on the intake, in at 108 ATDC then the exhaust should be in at 112 BTDC IHTHs Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: cam degreeing confusion [Re: JerseyJoe] #1198009 03/16/12 06:59 PM 03/16/12 06:59 PM
Joined: Jun 2008 Posts: 3,916 usa L lewtot184 master
lewtot184 master L Joined: Jun 2008 Posts: 3,916 usa	Quote: I'm using intake centerline method, when measuring at .050 valve lift does my dial need to be on the lifter or can it be on the valve retainer(factoring in my 1.5 ratio rockers)? I keep coming up with the same TDC but @ .050 (dial on the valve retainer) I'm not getting anywhere near the 106 centerline on the cam card. Any help is appreciated, Joe if you have a true 1.5 rocker multiply .050x1.5 and thats the cam lobes .050 number at the valve. you cannot check duration, lift, or anything for that matter using a hydraulic lifter. best, and simpiliest is check at the lobe.

Re: cam degreeing confusion [Re: lewtot184] #1198010 03/16/12 08:47 PM 03/16/12 08:47 PM
Joined: Dec 2004 Posts: 118 South Jersey JerseyJoe OP member
JerseyJoe OP member Joined: Dec 2004 Posts: 118 South Jersey	Thanks for the replies, I should have given more info. It's a RB motor and an XS290S Comp Cam, solid lifter and Crane ductile iron rockers. It was late last night and my math is shaky anyway, so I missed the .050 x 1.5 rocker part.

Re: cam degreeing confusion [Re: JerseyJoe] #1198011 03/17/12 02:43 PM 03/17/12 02:43 PM
Joined: Jan 2003 Posts: 4,587 St. John's Newfoundland 440newport master
440newport master Joined: Jan 2003 Posts: 4,587 St. John's Newfoundland	The first time I degreed a cam I wasn't coming up with anything close to what it was supposed to be either. It took me a while to realize I was trying to degree it from the #1 exhaust lobe instead of the intake.

Re: cam degreeing confusion [Re: 440newport] #1198012 03/17/12 05:51 PM 03/17/12 05:51 PM
Joined: Oct 2005 Posts: 8,868 Ontario, Canada S Stanton Don't question me!
Stanton Don't question me! S Joined: Oct 2005 Posts: 8,868 Ontario, Canada	Forget about the rocker ratio, it is totally insignificant. Measuring at the retainer all you want to do is make sure whatever reading you take on the upstroke is the same on the downstroke. So, if you use .075 on the upstroke, use .075 on the downstroke. Now, since all this is dependent on an accurate TDC, how did you do that with the heads on? And if you're checking at the retainer, make damn sure the shafts are bolted down tight.

Re: cam degreeing confusion [Re: JerseyJoe] #1198013 03/17/12 10:11 PM 03/17/12 10:11 PM
Joined: Dec 2004 Posts: 118 South Jersey JerseyJoe OP member
JerseyJoe OP member Joined: Dec 2004 Posts: 118 South Jersey	I found it. A bonehead, rookie mistake. I have a Comp Cams crank sprocket with the "O" on the keyway as well as the timing mark. Guess which one I lined up with the cam sprocket... I'm using the directions from Comp Cams, including a piston stop to find TDC. They're similar to other cam companies' directions, is this not the way to go?

Re: cam degreeing confusion [Re: JerseyJoe] #1198014 03/17/12 10:38 PM 03/17/12 10:38 PM
Joined: Oct 2005 Posts: 8,868 Ontario, Canada S Stanton Don't question me!
Stanton Don't question me! S Joined: Oct 2005 Posts: 8,868 Ontario, Canada	Quote: including a piston stop to find TDC was just checkin'

Re: cam degreeing confusion [Re: JerseyJoe] #1198015 03/17/12 11:36 PM 03/17/12 11:36 PM
Joined: Aug 2003 Posts: 43,129 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,129 Bend,OR USA	Quote: I found it. A bonehead, rookie mistake. I have a Comp Cams crank sprocket with the "O" on the keyway as well as the timing mark. Guess which one I lined up with the cam sprocket... I'm using the directions from Comp Cams, including a piston stop to find TDC. They're similar to other cam companies' directions, is this not the way to go? Dude, your not the only one that has done that Check the lobe centers on both valves Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

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