How to Pick Your own CamShaft better.

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Cudafever

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I was surfing around YouTube today, and found this video
The most complete explanation i have seen in one video.

Two Warning: It a long Video and it gets kinda technical at the end. But for someone that hasn't done a bunch of research on the science of a camshaft.......and want to learn some. This Is For You.

 
I think it was a very good video. Thanks. I think I will make it a sticky.
 
Cudafever said:
I was surfing around YouTube today, and found this video
The most complete explanation i have seen in one video.

Two Warning: It a long Video and it gets kinda technical at the end. But for someone that hasn't done a bunch of research on the science of a camshaft.......and want to learn some. This Is For You.

Click to expand...

I think everyone that asks "what cam should I run" should watch this video first. Even if you don't know the flow of your stock heads, someone has flowed them and can provide some numbers. If you have aftermarket heads, they have already been flowed or if you have yours ported, Then you should have them flowed so you know. I didn't have mine flowed when they were done and I sure wish I knew. :BangHead::BangHead:
 
toolmanmike said:
I think everyone that asks "what cam should I run" should watch this video first. Even if you don't know the flow of your stock heads, someone has flowed them and can provide some numbers. If you have aftermarket heads, they have already been flowed or if you have yours ported, Then you should have them flowed so you know. I didn't have mine flowed when they were done and I sure wish I knew. :BangHead::BangHead:
Click to expand...

Yup that's why i posted up here instead of small block section. the Sticky has most of the sb head flow numbers, already in this "sticky section"!!!!

Thanks to TurboGLH for taking the time to organised all of them.:thumbsup::thumbsup:
 
Agree, it IS a very good video. One comment though, he states several times that "it all comes down to head flow". While this is true, he never mentions that the INTAKE MANIFOLD needs to support the "head flow numbers". If the manifold and/or carburetor is restrictive, the head flow will not be what it was on the flow bench.

Otherwise, a good video. Thanks!
 
There is a lot more criteria that is not mentioned but it would have went on for hours if he did.
Tough enough to choose to watch a u tube video 30 minutes long.

But it"s a good place to start before you have a deeper conversation about cams!
 
I just when back and looked it was 50 minute long
and you notes all the chop in it right?

I bet you it was way, wayyy longer before he edit his video and post it up.

My videos are 2-3 hours long. they get edited down to 15 to 20 minutes long(most of the time)
I catch the chops that most people don't and didn't until i got my gopro.
 
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I thought about posting up in his comments when video 2.1 was coming out.
but i re-framed.
If he would have been a Mopar man i would have hit the fallow button. But he is a chev man and most of his video are on that.
 
Cudafever said:
I thought about posting up in his comments when video 2.1 was coming out.
but i re-framed.
If he would have been a Mopar man i would have hit the fallow button. But he is a chev man and most of his video are on that.
Click to expand...

Chevys have the same valve arrangement, firing order and distributor rotation as Mopar small blocks. The only difference between Chevy big blocks and Mopar big blocks is the distributor location and rotation direction. The two engine makes are astoundingly similar otherwise.
 
RustyRatRod said:
Chevys have the same valve arrangement, firing order and distributor rotation as Mopar small blocks. The only difference between Chevy big blocks and Mopar big blocks is the distributor location and rotation direction. The two engine makes are astoundingly similar otherwise.
Click to expand...

Except for head flow , a rat head is far superior to a normal wedge head , even a max wedge head.
CNC aftermarket closes the gap a bunch, but still no cigar.
I finally got around to watching the video , good refresher , but according to him , my crap is about right , fair amount over 700 h.p. , still doesn`t seem that good to me . Maybe the street gearing ------??
 
I just finished watching that video, thanks for posting! Helped me wrap/mold/meld hammer my head around engines a bit better.
Waiting for part 2.
He has 3 videos on rebuilding a 440.
Here is part 1

Oh when hes talking spring pressure and how that plays against crank rotation...he states like 5000 lbs approx. Doesnt sound right to me. All 16 springs arent compressed at same time?

Cudafever said:
I was surfing around YouTube today, and found this video
The most complete explanation i have seen in one video.

Two Warning: It a long Video and it gets kinda technical at the end. But for someone that hasn't done a bunch of research on the science of a camshaft.......and want to learn some. This Is For You.

Click to expand...
 
Have no intention on building any kind of chry Big Block............but watched and enjoyed all them videos.

In the process i found his video on cam shaft Spec that he did back in 2013
If you got and understand everything he had to say in the first video, this one might be boring. But he get into a little bit more detail, and has picture, on the difference between Lift, Duration,Intake Center line, Exhaust Center line, Lobe Separation and how that creates Overlap.
And this one is a little bit shorter.

Like i said if you understood 100% of what he said before this on will be a little dry, but if not it will help understand the spec of a cam better.
I guess this one is what "are" cam spec's and the first one I post up is more focused on how to pick a camshaft.
 
They say that you should always be broadening your horizon.
Does that apply to Stickys????
There is a 20 sec spot were you have to read lips, but you don't lose any part of any step.......so i decide to post it anyway.
Degreeing a Cam.

 
Just watched both those videos. Excellent. It's a matter of math and procedure. That's it.
Cudafever said:
Have no intention on building any kind of chry Big Block............but watched and enjoyed all them videos.

In the process i found his video on cam shaft Spec that he did back in 2013
If you got and understand everything he had to say in the first video, this one might be boring. But he get into a little bit more detail, and has picture, on the difference between Lift, Duration,Intake Center line, Exhaust Center line, Lobe Separation and how that creates Overlap.
And this one is a little bit shorter.

Like i said if you understood 100% of what he said before this on will be a little dry, but if not it will help understand the spec of a cam better.
I guess this one is what "are" cam spec's and the first one I post up is more focused on how to pick a camshaft.
Click to expand...


Cudafever said:
They say that you should always be broadening your horizon.
Does that apply to Stickys????
There is a 20 sec spot were you have to read lips, but you don't lose any part of any step.......so i decide to post it anyway.
Degreeing a Cam.

Click to expand...
 
Cudafever said:
I was surfing around YouTube today, and found this video
The most complete explanation i have seen in one video.

Two Warning: It a long Video and it gets kinda technical at the end. But for someone that hasn't done a bunch of research on the science of a camshaft.......and want to learn some. This Is For You.

Click to expand...

I don't think this guy mentioned how important intake closing is on cylinder pressure
 
I've watched this guy's videos before.... He has a shop and is knowledgeable but GET TO THE POINT! Keep it pithy..

One thing he does well is explaining ICL/ECL. LSA is a result of the math. So when you design a cam those figures determine the LSA.... They don't figure LSA first.... And two different sets of ICL and ECL will change the performance of the cam even if the LSA is the same. A 104/108 will act differently than a 102/110 even though the LSA is the same. Important in a performance cam.
 
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this was a great video to learn what are the main points to help choose your cams, kind of like the 80/20 rule. Was a good watch and thank you for posting.
 
Cudafever said:
I was surfing around YouTube today, and found this video
The most complete explanation i have seen in one video.

Two Warning: It a long Video and it gets kinda technical at the end. But for someone that hasn't done a bunch of research on the science of a camshaft.......and want to learn some. This Is For You.
Click to expand...

Just seeing this post by you for the first time. This video has been up before. I've been mostly picking cams this way for ever. It also depends on the build and target.
I've been telling people to choose there duration on the RPM band the cam operates in & what there are using it in as well as to get as much lift as the head allows nearly forever. A quick ramp rate for a beastly build, otherwise, it nearly doesn't matter. It's such small potatoes.

After that, the general guide rule of C lines for the new guy;

112 and up, smooth idle. Early F.I. systems liked this.
110 = typical hot rod
108 = more serious street machine, for sure on a manual trans car
106 & lower = more a race car cam

If you want to science out a cam, knock yourself out. For general hot rodding and medium duty race cars, I don't bother going nuts 90% of the time.
 
Ine time I put in a smaller cam on a fresh up cause my machine shop said it had more hp at lower rpm and same weather conditions it ran 2 tenths faster off the trailer. I wish I still had that car 511 cid 3060ib car street trim 5.50/5.60's dependscon the weather
 
273 said:
I Feel overlap is the most over looked camshaft spec, lift is the easiest spec to figure out. I like David Vizards approach, figure the LSA and overlap you want/need and the duration will take care of itself.

Not saying got to follow his formula 100% just like the basic idea of it.

Engine Camshaft Basics - Popular Hot Rodding Magazine
Click to expand...
Intake closing for me, a person can do alot with a big cam or a small cam to deal with one accepted pump gas compression. Plus if your doing a stroker you want to use the cubes available & and not throw it away .
 
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