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ok this is not on my 460. its a 292 yblock. its 60 over and 9 to 1 comp manual trans. im looking for something fairly mild. im new at cam stuff. was curious how lobe center affects low end power. lookin at a isky cam 270 duration .448 lift 112 lobe center 228 at 050. is lobe center and lobe seperation the same? I see grinds similar to this and they vary from 106 to 112. some show lobe seperation at one degree then different centerlines for intake and exaust. trying to learn how to make better cam choices. thanks.
 

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I'll give this a shot. No expert on cams, but I do know something about Y blocks. A couple of things for you...

Did you rebuild the engine, or do you know who did? The reason why I ask is that nearly all Y block pistons have a very low compression height, and a low deck height in terms of where the piston top ends up in the bore....and they nearly all are wildly optimistic in terms of rated compression. It normally takes a healthy cut off the block deck, and the heads, for that matter, in order to actually reach whatever rated compression the piston maker lists.

What I'm getting at is that, if you haven't actually done the math, so to speak, you likely have much less compression than 9:1, even with the .060 overbore,... which will make a difference as to cam selection.

Another thing to look at- although much less common- is that occasionally, guys will run across the HD292 from the '61-'64 heavy trucks. These are considered desirable because of the steel cranks and slightly heavier main webs. What is not commonly known, however, is that they use shorter rods & different pistons...and those pistons have a taller compression height & are not available nowadays. If a regular 292 piston is used, it sits waaay down in the hole at TDC. I've seen this a couple of times...the engine ends up around 7:1.

Not doubting your skills if you put it together, just mentioning a couple of areas to look at.

In terms of your original question :), no, lobe separation & lobe center are not the same thing. Lobe separation refers to the distance between the intake lobe centerline & the exhaust lobe centerline. Can't physically change it. The lobe centerline is an imaginary line that goes through the cam's center axis (from front to back), through the point of max lift on the lobe.

You can move the centerline's relationship to other things around, by advancing or retarding the cam.
 

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what are you intending to do with the y block? that [email protected] is not going to give a very smooth idle... so if youre doing any work with it or have it going into a heavy vehicle its probably not going to be very nice to drive on the street... may also not make enough vacuum for accessories... its no 460 ;)
 
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