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Twin cam head for the L6 from Derek at Datsunworks


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Yep, the mechanism is offered aftermarket.


Like those VNT turbos with a PWM controlled valve (easily driven by MS), there is stuff out there.


Now, a PWM driven electrically variable inlet cam, coupled with that PWM controlled VNT Turbocharger with a PID overboard boost unloading controller on the inlet, and a turbo tachometer to PID control to most efficient tip speed.


Someone say "extending torque"? What does 14psi off idle through a head flowing 310cfm on the intake make at 1,700 rpms? 7,700rpms? 9,700rpms? Even a measly 2.8 or 3.0 is a 5.7 or 6.0 at 14.7psi inlet flow...


Not that I thought about this any on those 24 hour transpacific flights...

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Audi (and probably others) are dumping boost like this on their 3.0 supercharged V6. It's a blower car that can actually increase boost with only a chip. No need for a pulley change.


The EFR line of turbos come with a shaft speed sensor flange cast in, among other goodies. I'd love to try tuning a car with closed loop turbo shaft speed control.


Re: cam control, yes PWM for sure, but PID needed as well, since they tend to have a "hold" DC. Any significant change in DC will rail the cam to min or max retard.


Not that I'm a likely customer for one of your heads without a windfall, but DOOOOO EEET!!  (VVT, that is.) Or make it doable for those who want to. Even having just a 2 position cam timing switchover can make a big difference in torqueband.


/end enabling

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I think the point is though that it isn't all that necessary. It is nice if there was sufficient meat left for those chasing the dragon to do so, but the only underlying reason to not run the Vtec killer type of deal is insufficient torque down low, with a 2 liter there is a noticeable difference, once you shift to a 2.4 liter and up the compression less of a difference, and I imagine with a 2.8 liter 6-cylinder there would be even less of a difference.


The few guys I know who did it went back, but that is because they were both base k20a3 cars. Relatively low compression, daily driven, you miss the 30-50 tq down low off the line. With the L6 I don't think that is much a concern given how traditionally flat those torque curves are.


Would be interesting to see, but I'm not sure interesting would be enough to warrant that much of an investment given how the head flows enough up top and should rev to try and save torque off the line. 


With all that aside, I would love to see a comparison, would be quite interesting.

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Given how much the k20 power curve keeps climbing, would love to see a built bottom end reving to the moon. 


Hang in there! 


That's what TonyD and Xnke are advocating. V2 is going on a friends car and he's gravitating towards a high revver. I think it would be worth it for the sound alone:)

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Speaking of V2...I assume it will use this.  




Not sure why you didn't go with this option in the 1st place...No issues with cams, gears, chains, VTEC, etc.  It pretty much eliminates all of your challenges.  You really should have consulted me more on this build in the early stages.  ;)

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A 3.2 or larger really is what you want for max power, these heads will support a 90x90 engine to 8,000+ rpms.


Sadly, only on block in 10 can take that bore.


So at most, I could only have three in my back yard suitable for that kind of build.



But a turbocharged 3.0 with custom billet crank, shortened snout, dry sump, flanged flywheel....oh yeah I been hoarding parts for a LONG while!

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Finishing up the last little bits I need.


Made the filter housings today. They use the same wire mesh and oiled foam filters that I use on my other manifold. I've been very happy with the filtration from the foam and saw no reason to do anything different. The housing probably isn't the best choice for power as it will disturb the air flow around the bell. Meh who cares. I like the look.




They still need finishing so the tooling marks from a well used CNC mill are visible.


I have a little boss on either side that will hold a set screw to hold them in place.




this started out as a 4"X8"X.75" piece of 6061.






Word from Crane is I'll have my cams by the end of next week.


Did an oil flow test and I'm getting excellent results up through the towers to the cam journals. The upper chain tensioner is getting plenty of flow as well.  I won't know beyond that until I get the cams installed.


Closer every day!

Edited by Derek
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Why did i dream about a custom Corvair billet block with custom cast heads that accommodate those 109mm+ bore VW Jugs with altered stud patterns, and a custom stroker crank, using SBC gear drive to relocate the cam lower in the block to clear the stroker crank...and dry sumped...


Why did I have this dream... How could it ever come to fruition?

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