TIGHT Lobe Distances
04-29-2005, 07:33 PM
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TIGHT Lobe Distances -How tight is to tight-
Take two lobes. Lets use a 220 xe-r lobe intake & exhaust. Put it on a 111lsa, icl. Gives a 2.5 IVC @ .2 lift. Good for a 6200-rpm peak but relatively flat curve.
The user doesn't want a high shift rpm but, wants more power with the lobes he has.
Real question: Can a pair of lobes for a given setup, have too much overlap?
With the 111, we're looking at 47* @ .006 & -2* @ .05 lift.
Ok, like mentioned he wants more "umph". Same lobes.... Slims it down to a 107lsa,icl. Now we are looking at 55* @ .006 & 6* @ .05 lift. Powerband is shifted down a bit, but is there a good bit more power in the new range?
Obviously, we have all seen larger camshafts with more overlap than this, so tuning will not be a nightmare so to speak... Looking at power here.
When does overlap become counter productive?
Take two lobes. Lets use a 220 xe-r lobe intake & exhaust. Put it on a 111lsa, icl. Gives a 2.5 IVC @ .2 lift. Good for a 6200-rpm peak but relatively flat curve.
The user doesn't want a high shift rpm but, wants more power with the lobes he has.
Real question: Can a pair of lobes for a given setup, have too much overlap?
With the 111, we're looking at 47* @ .006 & -2* @ .05 lift.
Ok, like mentioned he wants more "umph". Same lobes.... Slims it down to a 107lsa,icl. Now we are looking at 55* @ .006 & 6* @ .05 lift. Powerband is shifted down a bit, but is there a good bit more power in the new range?
Obviously, we have all seen larger camshafts with more overlap than this, so tuning will not be a nightmare so to speak... Looking at power here.
When does overlap become counter productive?
