I'd be callin Isky or ask Ted if that's where you got it. The amount of advance or retarding of the cam has no effect on the lobe centers. Both lobes move at the same time when you advance/retard the cam. The 112 degrees would probably work better in a blown motor than 107. Less overlap equals better cylinder filling in a blown motor.  

Oldmics

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Thats exactly the way I'm doing it but with a few more cylinders. It seems the RPM300 has an error on the cam card. Ted recommended 4 deg advance on the cam for my engine. Is that affected by the change in lobe center or should I still do 4 degrees? Chuck

         We may be (I may) confusing the termanology here. Lobe Centers are the difference between the intake and exhaust points of maximum lift. In crankshaft degrees. That is ground into the cam and cannot be changed except by regrinding the cam. If you are checking the difference between those points on your cam, it should work out to 112 degrees.

         If you are looking for a lobe centerline, that's the relationship to the crank of a particular lobe. Usually intake. That can be changed with offset keys or an adjustable pulley. If that's what you're trying to do, then do exactly what Tim and Ted are telling you.

        I'll shut up now before I confuse the issue further.

This is from the cam card.

My impression is that the 112 deg. represents the centerline and thats what I've been having problems with. My reading are 60 and 154 or 214=107Deg.

I guess my question is will this cam be ok to run on my 292 with blower? I really don't have the time or funds to get another one before Columbus. Chuck

Chuck.  I believe you’re talking ‘intake lobe centerline’ and not ‘ground centerline’.  Terminology is important at this point.  If your camshaft is measuring as being installed at 107° intake lobe centerline, then the exhaust is expected to measure out at 117° exhaust lobe centerline.  If the camshaft indeed checks out like this, then it is ground on 112° lobe centers.  107° + 117° / 2 = 112°.

As both Tim and Frank bring up, the ground lobe centerline does not change when moving the camshaft around but the intake and exhaust lobe centerlines in relation to TDC do change.  As the camshaft advances, the intake lobe centerline value becomes smaller while the exhaust lobe centerline value gets larger.  Be sure to check the exhaust lobe centerline also and when adding both the intake and exhaust centerline values and dividing by two, you are expected to get the advertised lobe centerline value.  Variances in the cam key location, cam gear keyway location, crank key location on the crankshaft, and the keyway location in the crank gear area are all players with where a camshaft initially sets up in an engine.  When all these variances stack up in the same direction, then the amount of error can be compounded.  When these variances have pluses and minuses, these variances will tend to cancel each other out.

As I mentioned earlier, be sure to double check the camshaft location by checking the lobes on the #6 cylinder.  If there is a large discrepancy, then start doing some rechecking.  If the cam still comes in at 5° advance, then backing it up 2-3° would be dirsirable but is not a show stopper if you can't get there from here.  If you don't have a multi-keywayed crank gear, then an option is an offset key but I'm not too much in favor of those for the Y simply due to the thickness of key itself being compromised.

When I started with the advance at 0deg I was having a mental problem with how I did it. Now with the 4deg advance I was forgeting to allow for that. It seems that I have a 4-5deg advance which is apparently in the ball park. I did not compare the intake to exhaust centers. Should I? Chuck in NH

Chuck, in a word yes. do the intake Centerline @ 107. this should be approx 5 degrees advanced which will help the low end. You'll be good with that I think. Like Tim said the 112 degree lobe centers should work pretty well with your 292. Just make SURE you have enough Fuel and fuel pressure.

  Set the way you have it would be good for the low end but it is my impression that with a blown motor you can close the intake a little later since you are stuffing A/F into the engine anyway.  most "Blower" cams that I have seen are ground on 112* -116* centers.  If Ted told you to advance 4* I'd go with his recommendation, his experience trumps mine.

Tim, I think you want to close the intake a little early to avoid blowing Fresh mixture out the exhaust pipe. I'm thinking (careful now!) the blower will take care of his midrange/top end issue, while the advanced cam timing will help him move a fairly heavy car out of the hole.

     You are 100% correct on the 112 to 116 center with blower. That was hard for me to believe at first, I am used to much more overlap, but it works. 

     By the way, Jake is Friggin awesome! wish I could have found your house now!

Comp?

Aren't you talking about closing the exhaust a little early, as in less overlap.  Intake will be closing ABDC weather it's 50* or 54* the exhaust has long since closed.

Jake looks a lot better now than back in Jan.  You're welcome any time.