Powell Machine had some storm damage but let's talk cams anyway.

[toolmanmike]

He has the generator running and sets outside his garage and records content. Love it. Let's talk about LSA and such.

 

[Garrett Ellison]

I've been following the Weingartner Camshaft Challenge, too. Even though it's a 408 LS3 based contest, it's going to be interesting (TO SAY THE LEAST!) what testing shows.

 

[toolmanmike]

I've been following the Weingartner Camshaft Challenge, too. Even though it's a 408 LS3 based contest, it's going to be interesting (TO SAY THE LEAST!) what testing shows.

He is haveing fun with that. I like the idea behind it.

 

[Bewy]

Like a lot of others, Powell claims that the intake closing is one of the two most important cam events. Sorry, could never see the logic.
An engine needs to ingest air to make hp; ingest more air, more hp. At IVC, there is zero air ingested. I would think what happens before the IVC is more important when air is still flowing into the cyl &.....

 

[GTX JOHN]

I agree with you = at least on engines for performance or racing purposes.

Like a lot of others, Powell claims that the intake closing is one of the two most important cam events. Sorry, could never see the logic.
An engine needs to ingest air to make hp; ingest more air, more hp. At IVC, there is zero air ingested. I would think what happens before the IVC is more important when air is still flowing into the cyl &.....

 

[AJ/FormS]

Like a lot of others, Powell claims that the intake closing is one of the two most important cam events. Sorry, could never see the logic.
An engine needs to ingest air to make hp; ingest more air, more hp. At IVC, there is zero air ingested. I would think what happens before the IVC is more important when air is still flowing into the cyl &.....

well, he was talking about TWO (or Three) events, and how to fill the time between them, for the Cam-Challenge.
I'm just a shade-tree mechanic, and I understood exactly his point, and those exact points are what I used to select cams for my cars over the years; as I learned what he also did. It was like he was talking straight at me!
My first cam was waay too big.
My second cam was a lil small.
#3 is a winner. But it took three tries and 4 years to get there. The learning curve was expensive.

 

[Bewy]

ALL of the events have some importance, some more so than others. I do not agree with Powell's selection of the most important event.
That would only be determined by dyno testing, not some computer program, because there is no computer made that can guess what all the variables that are happening in the the engine are doing/will do.
Piston speed [ PS ] is very important. It is needed to create vacuum to pull air into the cyls; air makes the hp. At TDC & BDC, PS is zero. Somewhere between TDC & BDC, is the maximum PS.
I believe that D. Vizard's dyno testing of 19,000+ cams found the sweet spot. And it is NOT IVC. It is the relationship between valve at or near max open....& piston speed. And valve max open corresponds to the LSA....

One cam was too big, one too small? That is what the 128 rule was supposed to fix; you buy one cam...& it is the correct cam.