T67POWER
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- Sep 30, 2009
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I chose to put this here instead of the transmission section, because it has to do with small block cam selection.
-------------------------------------------------------------------------let
When choosing a cam for that small block, the biggest thing one should consider is the converter.
Most everybody knows this --BUT--we still push the limits of cam size a little to far on average.
The duration of the cam is always a huge topic-- BUT--It all comes down to where the peak torque is going to fall in the rpm range of the engine.
How high your torque converter stall speed is and how close that stall speed is, to the peak torque of the engine, is most important.
This alone eliminates most guess work.
If you need a cam ,then you must know your stall speed first.
I will use a stock torque converter as a reference.
Make sure you know where the peak torque occurs FOR THE CAM you selected or suggested for someone, and make sure that it is on average around 700 to 1700 rpms over your stall speed.
700 rpm's being low performance.(smallest cam)
1700 rpm's being high perforamce (biggest cam)
EXAMPLE :Someone has a stock torque converter in their car with a stall speed of 1800 rpms.
The cam window is found by adding 700 to your stall speed for a low performance engine.
The cam window is found by adding 1700 to your stall speed for a high performance engine.
1800 rpm's stall speed for stock converter + 700 rpm's = 2500 rpm's
LOW PERFORMANCE ENGINE
You would want your peak torque to occur no lower then 2500 rpm's
1800 rpm's stall speed rpm's + 1700 rpm's = 3500 rpm's
HIGH PERFORMANCE ENGINE.
You would want your peak torque to occur no higher then 3500 rpm's
Remember this is for picking a cam for the STOCK TORQUE CONVERTOR that"s already in your car.
This does not apply to towing and or a full time drag car.
Let me know if it works for you and will be glad to hear any opinions on it.
:cya::burnout:
-------------------------------------------------------------------------let
When choosing a cam for that small block, the biggest thing one should consider is the converter.
Most everybody knows this --BUT--we still push the limits of cam size a little to far on average.
The duration of the cam is always a huge topic-- BUT--It all comes down to where the peak torque is going to fall in the rpm range of the engine.
How high your torque converter stall speed is and how close that stall speed is, to the peak torque of the engine, is most important.
This alone eliminates most guess work.
If you need a cam ,then you must know your stall speed first.
I will use a stock torque converter as a reference.
Make sure you know where the peak torque occurs FOR THE CAM you selected or suggested for someone, and make sure that it is on average around 700 to 1700 rpms over your stall speed.
700 rpm's being low performance.(smallest cam)
1700 rpm's being high perforamce (biggest cam)
EXAMPLE :Someone has a stock torque converter in their car with a stall speed of 1800 rpms.
The cam window is found by adding 700 to your stall speed for a low performance engine.
The cam window is found by adding 1700 to your stall speed for a high performance engine.
1800 rpm's stall speed for stock converter + 700 rpm's = 2500 rpm's
LOW PERFORMANCE ENGINE
You would want your peak torque to occur no lower then 2500 rpm's
1800 rpm's stall speed rpm's + 1700 rpm's = 3500 rpm's
HIGH PERFORMANCE ENGINE.
You would want your peak torque to occur no higher then 3500 rpm's
Remember this is for picking a cam for the STOCK TORQUE CONVERTOR that"s already in your car.
This does not apply to towing and or a full time drag car.
Let me know if it works for you and will be glad to hear any opinions on it.
:cya::burnout:
