2 cam questions
04-21-2009, 01:22 AM
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2 cam questions okay so a question just occured to me about cam specs....
1. so i believe when it comes to LSA a 112 will have a broader powerband with a little less peak when compared to the 114 (for arguements sake).
so the 114 will be a little more peakish and have a little less low and mid range....correct?
2. question 2 kind of ties into question 1.....if you have a cam with specs 230/230 595/595 112+2......i understand that the +2 at the end just means you have degrees of cam timing ground in....so in a sense, if you have a cam with advance ground in, you basically are doing the same thing as getting a cam with a higher LSA (just taking away a little low and mid and adding up top, am i right? if so what would be the point in having say a 110 or 112 with advance ground in when you could just buy a cam with a higher lsa? hopefully some can make some sense of this, thanks
1. so i believe when it comes to LSA a 112 will have a broader powerband with a little less peak when compared to the 114 (for arguements sake).
so the 114 will be a little more peakish and have a little less low and mid range....correct?
2. question 2 kind of ties into question 1.....if you have a cam with specs 230/230 595/595 112+2......i understand that the +2 at the end just means you have degrees of cam timing ground in....so in a sense, if you have a cam with advance ground in, you basically are doing the same thing as getting a cam with a higher LSA (just taking away a little low and mid and adding up top, am i right? if so what would be the point in having say a 110 or 112 with advance ground in when you could just buy a cam with a higher lsa? hopefully some can make some sense of this, thanks
04-21-2009, 02:39 AM
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okay so a question just occured to me about cam specs....
1. so i believe when it comes to LSA a 112 will have a broader powerband with a little less peak when compared to the 114 (for arguements sake).
so the 114 will be a little more peakish and have a little less low and mid range....correct?
2. question 2 kind of ties into question 1.....if you have a cam with specs 230/230 595/595 112+2......i understand that the +2 at the end just means you have degrees of cam timing ground in....so in a sense, if you have a cam with advance ground in, you basically are doing the same thing as getting a cam with a higher LSA (just taking away a little low and mid and adding up top, am i right? if so what would be the point in having say a 110 or 112 with advance ground in when you could just buy a cam with a higher lsa? hopefully some can make some sense of this, thanks
1. so i believe when it comes to LSA a 112 will have a broader powerband with a little less peak when compared to the 114 (for arguements sake).
so the 114 will be a little more peakish and have a little less low and mid range....correct?
2. question 2 kind of ties into question 1.....if you have a cam with specs 230/230 595/595 112+2......i understand that the +2 at the end just means you have degrees of cam timing ground in....so in a sense, if you have a cam with advance ground in, you basically are doing the same thing as getting a cam with a higher LSA (just taking away a little low and mid and adding up top, am i right? if so what would be the point in having say a 110 or 112 with advance ground in when you could just buy a cam with a higher lsa? hopefully some can make some sense of this, thanks
EFFECTS OF LOBE SEPARATION ANGLE
LSA........................NARROW........WIDE
Intake Open............Earlier............Later
Intake Close............Earlier............Later
Exhaust Open..........Later..............Earlier
Overlap...................More...............Less
Cylinder Pressure.....Gain...............Lose
Idle Quality.............Worse.............Better
Idle Vacuum............Less...............More
Torque Curve...........Peakier...........Flatter
Peak Torque.............More...............Less
High RPM.................Drops Off........Hangs On
#2. not LSA, you're thinking of the installed centerline... how the cam timing is phased to the crankshaft coming to TDC.
the lobe seperation angle is ground into the cam. cant be changed.
its the phase angle between the max lift on the intake and exhaust lobes. narrow lsa = more overlap.
a 112lsa cam will install at a 112 installed centerline.
a 112+2 LSA cam with 2 degrees of advance ground in will degree out to a 110 ICL when installed by "lining up the dots".
with an adjustable timing chain you can also degree in the cam and change the installed centerline.
http://www.popularhotrodding.com/eng...ion_angle.html
Last edited by Ryan72; 04-21-2009 at 02:46 AM.
04-21-2009, 10:04 AM
#4
Ryan's chart is a good (quick and dirty) rule of thumb regarding LSA. Nice post.
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COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
