Vari-Cam

[RAMM]

Please do! Stick a really strange cam in that 400 and get the Cam-A-Go to really influence the power curve. Would be VERY interesting. J.Rob

[kid7755]

That's the plan when time allows. It's gonna have to go back together as is to "calibrate" the hopefully new neighborhood dyno. Then I'm gonna hit up Randy Malik to borrow a couple cams. He has about 600 SBC cams.

[PackardV8]

While we're on this subject, I've noticed Jon Kaase, in addition to his small bore, short rod, long stroke short block has used some of the tightest LCA I've ever seen. IIRC, one year he was under 100 degrees.

Can someone with the software expertise plot a graph of what LCA would theoretically produce the most power at each 1,000 RPMs from 3,000-7,000?

The next logical step would be the cam-within-a cam as used by the Viper engines. It can vary the exhaust-to-intake LCA.

[lada ok]

While we're on this subject, I've noticed Jon Kaase, in addition to his small bore, short rod, long stroke short block has used some of the tightest LCA I've ever seen. IIRC, one year he was under 100 degrees.

Can someone with the software expertise plot a graph of what LCA would theoretically produce the most power at each 1,000 RPMs from 3,000-7,000?

The next logical step would be the cam-within-a cam as used by the Viper engines. It can vary the exhaust-to-intake LCA.

1969 Porsche flat 12 4494 cc ..104-104 - 105-75 ... 47 years past

[Stan Weiss]

While we're on this subject, I've noticed Jon Kaase, in addition to his small bore, short rod, long stroke short block has used some of the tightest LCA I've ever seen. IIRC, one year he was under 100 degrees.

Can someone with the software expertise plot a graph of what LCA would theoretically produce the most power at each 1,000 RPMs from 3,000-7,000?

The next logical step would be the cam-within-a cam as used by the Viper engines. It can vary the exhaust-to-intake LCA.

1969 Porsche flat 12 4494 cc ..104-104 - 105-75 ... 47 years past

Unless you have done some rounding, or I misunderstand the meaning of 105-75. But that = 105

Stan

[pamotorman]

original instructions for the vari-cam. worked great in SBC

[Walter R. Malik]

original instructions for the vari-cam. worked great in SBC

I was gonna try one but, I couldn't find one.

With a crank trigger ignition it seems it would work even better.

[PackardV8]

Like most good ideas, variable cam timing had to wait for technology to catch up with theory. Most recently designed engines have some form of it.

With a crank trigger ignition it seems it would work even better.

Agree, love them crank triggers, but most lawn mowers have had crank triggers for the past hunnerd years. It's the computer control and the interface with the cam position sensor which makes it all work so well, make so much power and get such good fuel mileage at the same time.

I was gonna try one but, I couldn't find one.

And back to the VariCam; I'm trying to remember ever seeing one on a serious performance build. Add it to the list of gimmicks Hot Rod has flogged over the years. (Remember the discussion of the Schaller Quarter Speed Cam?) It is such a crude device and the lack of computer control of ignition and injections is likely why it didn't catch on and become a staple in all street/strip builds. As valve spring loads increased, it's also likely the simple hairpin mechanism just couldn't cope.

[pamotorman]

yes they did break the pig tail spring. I still have one here for a chevy

[Kevin Johnson]

I'll try to find a link if anyone is interested.

Thanks
Randy

You should do that. Remember that it may take some time before any particular interested person responds. With a Wayback search the information may be retrievable; lacking the referent probably not. I do not think (could surely be wrong!) that archived web data can necessarily be found via Google.