Using Delta values to compare lobe duration
10-25-2006, 09:56 PM
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Using Delta values to compare lobe duration Ive been discussing cam designs and I like the cam used in this build http://www.exoticperformanceplus.com...Car.php?car=39
and in order to properly compare the duration I used a delta value
the 402 used a 220/224 duration and mathmatically the consequent size for a 363 would be 197/201.
Is this an effective way of comparing duration or is it too simple?
If not what is the proper way to compare cam "sizes" to different motors? disregarding all the other variables like intake, heads, exhaust etc..
and in order to properly compare the duration I used a delta value
the 402 used a 220/224 duration and mathmatically the consequent size for a 363 would be 197/201.
Is this an effective way of comparing duration or is it too simple?
If not what is the proper way to compare cam "sizes" to different motors? disregarding all the other variables like intake, heads, exhaust etc..
10-26-2006, 12:56 AM
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Originally Posted by 02sierraz71_5.3
Ive been discussing cam designs and I like the cam used in this build http://www.exoticperformanceplus.com...Car.php?car=39
and in order to properly compare the duration I used a delta value
the 402 used a 220/224 duration and mathmatically the consequent size for a 363 would be 197/201.
Is this an effective way of comparing duration or is it too simple?
If not what is the proper way to compare cam "sizes" to different motors? disregarding all the other variables like intake, heads, exhaust etc..
and in order to properly compare the duration I used a delta value
the 402 used a 220/224 duration and mathmatically the consequent size for a 363 would be 197/201.
Is this an effective way of comparing duration or is it too simple?
If not what is the proper way to compare cam "sizes" to different motors? disregarding all the other variables like intake, heads, exhaust etc..
10-26-2006, 01:13 AM
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Originally Posted by GOaT Cheese
It would be completely impractical to compare an identical cam that has been reduced proportionately to compensate for decreases in displacement. The factors that determine displacement are not linear, therefore the thermal characteristics of each displacement are completely unique and would require a unique cam design. For instance you can't simply reduce a cylinders swept volume without changing bore, or stroke, or both, and consequently with that you effectively alter bore to stroke ratio, rod to stroke ratio, quench area, crown height, and most importantly intake and exhaust velocities. By doing so the mechanical advantages and disadvantages must be exploited for maximum power output. There cannot be a simple universal mathematical equation to blanket all cam needs for a given displacement based on one lobe pattern that may work well in a given engine.
Thanks for the answer.
10-26-2006, 10:40 AM
#4
Originally Posted by 02sierraz71_5.3
Ive been discussing cam designs and I like the cam used in this build http://www.exoticperformanceplus.com...Car.php?car=39
and in order to properly compare the duration I used a delta value
the 402 used a 220/224 duration and mathmatically the consequent size for a 363 would be 197/201.
Is this an effective way of comparing duration or is it too simple?
If not what is the proper way to compare cam "sizes" to different motors? disregarding all the other variables like intake, heads, exhaust etc..
and in order to properly compare the duration I used a delta value
the 402 used a 220/224 duration and mathmatically the consequent size for a 363 would be 197/201.
Is this an effective way of comparing duration or is it too simple?
If not what is the proper way to compare cam "sizes" to different motors? disregarding all the other variables like intake, heads, exhaust etc..