“Real Camshaft Science”

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12many

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Call a cam company, ask on a forum, pick the one at the bottom of the page in the catalog, or any other number of ways to pick a cam. Many tools are available for one to educate themselves and make a decision. Read up, ask questions, research and process it all. Just like when you were in school. Simple as that. This is just one example of what’s out there. You can make a choice using one method, take the advice of one person, or use any combination of all sources at your disposal to make a good decision.

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Cam discussions remind me of how older engineers - real engineers - laugh at the kids coming out of engineering school when they turn in their first design.

They've been tasked with designing a machine that harvests corn....and the drawings look excellent. 3D CAD.

The laughter comes when you look at their dimensioning and they've carried out each value to the 6th decimal place...because that's what the computer spit out.

The older engineers understand that a dimension of 132.5" inches is plenty good.....132.498508" is not gonna buy you anything other than confusion and misery.

The other day I had a guy moaning that the cam company he was talking to gave him a recommendation on a cam that had .525" lift when he really needed .530".

They say that being a police officer carries with it one of the highest rates of suicide of any occupation. I always assume working at a cam company would be at least a little higher. Maybe .00034" and 1 degree higher.
 
I think the main problem people have when choosing a cam or even coming up with the full engine/driveline combo is they haven't narrowed down what they want just some vague sense of it. They seem to pick things out of thin air with little thought how everything fits to getter. Or expect too much of their car to be the jack of all trades without any compromises, the more you want your car to do the more complicating the task of engineer and designing your ride and probably more likely a disappointment on each front.

I like David Vizards basic premises on cams.
 
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Always liked the Mopar 340 Camshaft as a base line, can't go wrong there.

Then then people can tweek their lift, duration and lobe centers from there for the application they desire.

Me I will be staying with the:
430/444 lift
268/276 Duation
and 112 lobe centers

For street driven cars, knocking around the neighborhoods here.
 
As a guy who is picking a cam right now and reading this- I want to add :
In some ways the old skool engines we know and love are getting a big make over with this new found technology. Back when you opened a catalog and bought a 3/4 race cam vs a high lift cam. Pretty easy peasy to say the least. Now overlap and duration seems to be big. Spring bind and volume metric efficiency is big. It’s very overwhelming and it’s easier to take someone’s word for advice then learning a new language. This is especially true when your intentions was to take a 45 year old low mileage engine and drop a cam in it for more power. Mind you those 45 year old engines (69-318 in my case) 45k was about 1/2 it’s expected life. Lol! Modern Hemi 5.7 are just breaking in at 45k and are being used until 200k.
Anyhow- thank you to all over the years who have added to this information. It’s good reading to me. :thumbsup:
 
I am partial to the 292 purple cam. Many hate it but I like it! 108° lobe separation version not the 114° lobe separation just to be clear. A little off the original topic.
 
I like David Vizards basic premises on cams.
I’ve been reading his various books and articles for about 40 years. I used his method for determining cam events as well as Holley carb tuning. Is there a better way? Likely, but I chose one method and have exceeded my performance goals with my setup. High 11’s (and I’m not finished just yet!) with a baby cam’d stroker in an aerodynamically challenged vehicle. :)
 
It says a lot that a company like Honda or Lexus - with a big research budget and plenty of time on their hands - adopted variable cam timing long ago. They can get power and MPG...but not with a fixed cam.
 
It says a lot that a company like Honda or Lexus - with a big research budget and plenty of time on their hands - adopted variable cam timing long ago. They can get power and MPG...but not with a fixed cam.

Best we could do is use something like Rhodes, and if you go Rhodes rollers and high ratio rockers you could build a fairly flexible engine power/economy cam/valvetrain.
 
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