comp 216/220?
09-24-2004, 01:27 PM
#21
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Originally Posted by RED2K
i have the 216/220 and i hate it. a true POS of a cam campared to others i have had. Ok so I have had only this one but i think i would have liked a 212 218 better
09-24-2004, 01:37 PM
#24
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Originally Posted by SportSide 5.3
Roger,
I still haven't grasped your logic on adding more exhaust duration to provide a fatter power band.
Few questions:
-How does more exhuast duration make tuning easier? I've always heard the other way around, where more exhaust duration causes more misfire codes.
-Again, if we are intake limited, why add more exhaust duration?
-Shouldn't the valve events match the head flow and the users requirments?
I'm just lost on most of your cam specs, where almost all favor 4* or more of exhaust duration. Hopefully, you don't take my questions the wrong way. I've heard of good results and am trying to figure it out.
BTW:
Would it be possible for you to list the valve events of say the asp kicker?
Thanks.
I still haven't grasped your logic on adding more exhaust duration to provide a fatter power band.
Few questions:
-How does more exhuast duration make tuning easier? I've always heard the other way around, where more exhaust duration causes more misfire codes.
-Again, if we are intake limited, why add more exhaust duration?
-Shouldn't the valve events match the head flow and the users requirments?
I'm just lost on most of your cam specs, where almost all favor 4* or more of exhaust duration. Hopefully, you don't take my questions the wrong way. I've heard of good results and am trying to figure it out.
BTW:
Would it be possible for you to list the valve events of say the asp kicker?
Thanks.
09-24-2004, 02:00 PM
#27
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Snake Eater.
I understand that this has worked for you, but by picking the correct camshaft for your application this would not be needed. We just don't need a bunch of guys advancing their cams because they lack low end. Thats just the wrong way to deal with things, if you get what I'm saying.
Now with the cam selection topic.
Ok here we have some information. A wise man's take on cam selection and below that. Flow numbers for a stock 5.3 head.
At each given lift. Divide the exhaust duration by the intake.
.100 = 85.7%
.200 = 72.6%
.300 = 67.6%
.400 = 69%
.500 = 74.7%
.550 = 76%
.600 = 76.9%
-----------
Hmmmm. Imagine finding those flow numbers with your LT headers and cruddy manifold in place. Would the logic of reverse splits start to make sense?
Alot go buy headers, run the stock intake manifold on there and install a standard split, and run n/a. Whats the logic?
Still, so lost on why standard splits are so popular.
I understand that this has worked for you, but by picking the correct camshaft for your application this would not be needed. We just don't need a bunch of guys advancing their cams because they lack low end. Thats just the wrong way to deal with things, if you get what I'm saying.
Now with the cam selection topic.
For CID under 400, 75% exh ratio to intake dictates a single pattern cam. For every % point over you need to crutch the intake 1/2 degree of duration
Chamber 61.15 cc 0.100 0.200 0.300 0.400 0.500 0.550 0.600
Intake 200 cc 63 128 179 210 218 221 226
Exhaust 70 cc 54 93 121 145 163 168 174
Intake 200 cc 63 128 179 210 218 221 226
Exhaust 70 cc 54 93 121 145 163 168 174
At each given lift. Divide the exhaust duration by the intake.
.100 = 85.7%
.200 = 72.6%
.300 = 67.6%
.400 = 69%
.500 = 74.7%
.550 = 76%
.600 = 76.9%
-----------
Hmmmm. Imagine finding those flow numbers with your LT headers and cruddy manifold in place. Would the logic of reverse splits start to make sense?
Alot go buy headers, run the stock intake manifold on there and install a standard split, and run n/a. Whats the logic?
Still, so lost on why standard splits are so popular.
09-25-2004, 10:44 AM
#29
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Duration= amount of time valve is spent open
Valve events=timing of the valves. This deals with the advancing/retarding. Not sure what you mean by this:
EDIT:
Just realized this is incorrect.
For ex.
Advancing a cam with to much exhaust duration to start with, is not helping. You are closing the valves sooner.
Valve events=timing of the valves. This deals with the advancing/retarding. Not sure what you mean by this:
(no matter what duration)
Just realized this is incorrect.
For ex.
Advancing a cam with to much exhaust duration to start with, is not helping. You are closing the valves sooner.
09-25-2004, 01:42 PM
#30
TECH Veteran
Originally Posted by SportSide 5.3
Duration= amount of time valve is spent open
Valve events=timing of the valves. This deals with the advancing/retarding. Not sure what you mean by this:
Valve events=timing of the valves. This deals with the advancing/retarding. Not sure what you mean by this: