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Discussion Starter #1
Since this is all about cam tech,would anyone here "in the know" be willing to discuss what's needed to select proper valve events? What are the things to look at based on displacement,head flow,valve size,mcsa,manifold type/size,carb/efi,desired peak rpm,etc. How should a guy select a cam based on valve events instead of just a lift, duration and lsa numbers? I know you can find valve events from these and icl #'s,but what's the important things to look at for cam selection?
 

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Yeah, I'd like to know this too, but I seriously doubt it's gonna happen! Most good cam guys go to the grave with thier knowledge! lol But I'm all ears. Anybody? sound of crickets.....
 

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Yeah, I'd like to know this too, but I seriously doubt it's gonna happen! Most good cam guys go to the grave with thier knowledge! lol But I'm all ears. Anybody? sound of crickets.....
x2 on that. I think its a deal that making camshafts is just like anything else, it takes years of research and study to become good at it to the point where you can do it for a living. No different than it takes years to learn anything else to a professional level and asking these people to just give that info up is a tough or impossible sell.
 

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lots of it is just plain experience with engines and customers /vehicles etc...i've done this for 20 years so had my share of time with it. when you really grind your own cams and not ordering from a book , you get the real idea of what it takes with lobes , material and combinations of parts to make a good thing. plus having a great cam mentor is some key fruit, you want a rookie dr. cutting into you or a seasoned veteran thats done it a few times.
 

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lots of it is just plain experience with engines and customers /vehicles etc...i've done this for 20 years so had my share of time with it. when you really grind your own cams and not ordering from a book , you get the real idea of what it takes with lobes , material and combinations of parts to make a good thing. plus having a great cam mentor is some key fruit, you want a rookie dr. cutting into you or a seasoned veteran thats done it a few times.
Speaking of experts, hey Dan how's Roger coming along with my clutch?;)

Corey
 

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lots of it is just plain experience with engines and customers /vehicles etc...i've done this for 20 years so had my share of time with it. when you really grind your own cams and not ordering from a book , you get the real idea of what it takes with lobes , material and combinations of parts to make a good thing. plus having a great cam mentor is some key fruit, you want a rookie dr. cutting into you or a seasoned veteran thats done it a few times.

So is it trial and error and experiences with some science thrown in there? the result might be the same but the Engine build programs on the market use some math formulas...... Cu. in., head flow, rpms range, etc....to derive a formula for a cam selection. You just might do the same thing in a nano-second in your head.

Those $1,000+ ea. IRL cams you ground were they just " off the top of your head"? Well they did win at Indy didn't they .......... ;)

G-

Jon
 

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good question , he's a one man army down there so i dont bother too much.. should have it handled anytime
 

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lots of science , little luck and a lot of ambition..
any good camshaft comes from track time and real world conditions..the IRL cams were tweaked and tweaked and tweaked every 3 months for max power at all times without dropping valves. yes won the race with eddie cheever in 98' , had 11 pole positions in 2 seasons and 7 wins in the series... ahh the good old days

So is it trial and error and experiences with some science thrown in there? the result might be the same but the Engine build programs on the market use some math formulas...... Cu. in., head flow, rpms range, etc....to derive a formula for a cam selection. You just might do the same thing in a nano-second in your head.

Those $1,000+ ea. IRL cams you ground were they just " off the top of your head"? Well they did win at Indy didn't they .......... ;)

G-

Jon
 

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Discussion Starter #10
How does a guy learn how to decide on a cam that's "in the ballpark" for his setup without calling some cam tech line with a rep who may or may not know a thing about what works? It'd be good for everyone if more people could make more educated decisions on a baseline cam and a little more knowledge on what to change to improve their baseline. I don't want to know what it takes to design and grind lobes,just how to zero in on the right cam for a given application without buying half a dozen cams and none being right.
 

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How does a guy learn how to decide on a cam that's "in the ballpark" for his setup without calling some cam tech line with a rep who may or may not know a thing about what works? It'd be good for everyone if more people could make more educated decisions on a baseline cam and a little more knowledge on what to change to improve their baseline. I don't want to know what it takes to design and grind lobes,just how to zero in on the right cam for a given application without buying half a dozen cams and none being right.
Ghetto Math will get you in the ball park. Do you want me to post it?
 

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^^^

Inquiring minds want to know.....................


G-
 

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Discussion Starter #13
Ghetto Math will get you in the ball park. Do you want me to post it?
I'd appreciate it if you don't mind. I didn't mean to come off like I wanna know guys trade secrets,just want to know more about how to select valve events rather than just lift and duration. Thanks guys.
 

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everyone wants your head flow but misses the fundamentals of things sometimes. ... just basics like bore , stroke and rod length are commonly over looked areas people go wrong on camming engines , combined with 27000 heads nowadays its even more confusion for the average joe.
 

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What does rod length have to do with it?


G-
 

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^^^

thats why I asked.....maybe the faster the pistons pulls away from TDC you can afford to use a bigger lobe....or add duration..... or ....


G
 

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everyone wants your head flow but misses the fundamentals of things sometimes. ... just basics like bore , stroke and rod length are commonly over looked areas people go wrong on camming engines , combined with 27000 heads nowadays its even more confusion for the average joe.
Engine Combination + Induction Specs + Desired Power RPM range = Camshaft

This is what I do.
 
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