cam ?

[45minilatemodel]

what would be the best cam for stroked 60 over,stock intake,500 holley carb on 1/5 mile dirt track....thanks jim

[DOCTOR FIELDS]

How many rpms do you plan on turning this engine?

[45minilatemodel]

i dont have a determined rpm,doesnt matter to me,just need an idea of what cam suits the parameters i stated.200 stroke,60 over,stock intake and 500 holley,solid lifters on a 1/5 mile dirt track...

[DOCTOR FIELDS]

You need to have an idea of about how many rpms you will be turning the engine before a cam can be selected. For example, you don't want to buy a 300 duration 455 lift cam if you only turn it 6000 rpms. Cams are designed to work in specific rpm ranges.

[45minilatemodel]

ok, ill say 7200-7800...and i know that cams are designed to work in specific rpm ranges,but i also know that some cams are suited better for short tracks and some intermediate tracks and some for larger tracks.im on a 1/5 mile dirt track where were in a corner alot and need torque.we run a 500 holley,the open port head and a modified schoenfeld sb chevy header,were able to turn 8500 if we want.we need a cam with a great midrange and decent top end.right now were running a 455 lift cam but not sure which one,i think its a 300 or 308.im not trying to be an ass here,im just use to building sb dirt motors and ive always made my cam selection on the the tracks size and shape first,weight of the car,then fuel dilivery system being used,were new to these 4 bangers and just wanted your recomendation and where to get the cam you suggest.....thanks jim

[zackbandyr12]

try a 290, change cam carriers, if ur runnin a 300, 308.... but the rpms might be to high for a 290, but trail and erea will tell

[45minilatemodel]

thanks zack,..fields how do you determine cam selection?

[DOCTOR FIELDS]

The main thing i look at while selecting a cam is RPM range. The rule of thumb is to exceed the range by 300 rpms. For example: If you have a cam that runs out at 6500, you want to turn the engine up to 6800 for the most performance. Thats the simple way of selecting a cam...You can get technical and put the head on a flowbench, find what lift the head flows best at, select or have a cam custom ground to your specs, then dyno test to see where the HP & Torque numbers drop off, then select a final drive ratio that will put you in that range. Most Chevette racers dont have access or can afford to get all that done.