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Derek

Twin cam head for the L6 from Derek at Datsunworks

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5 hours ago, turbogrill said:

For us that hasn't followed the 50 pages in this thread, is it possible to get a 3-4 sentence summary regarding progess, cost and expected use case?

Not sure this is a Champcar legal head, but I won't protest you if you run it.

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8 hours ago, zack_280 said:

Not sure this is a Champcar legal head, but I won't protest you if you run it.

 

The rules are clear, non-OE cylinder head is 100pts.

 

If Derek gives me one for free I would be happy to stress it for him. It would involve irresponsible drivers and ziptie loving mechanics...and somehow beer.

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On 3/27/2018 at 6:42 AM, Derek said:

Owner of V3 sent me an update picture.

 

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Pretty freaking cool if you ask me.

 

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I checked the 3D model and tilted the amount they did the intake side of the water jacket is just below the outlet so hopefully there won't be any steam pocket issues.

 

Snifff....I'm so proud:)

 

I wish I would have loved the ladder out of the background 

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VCT Progress!

 

So slowly but surely I have been chipping away at making the VCT fit in the available space. What a freaking PIA. The problem with timing chains is you are constrained distance wise by the pitch of the chain and the adjustment can be a bit coarse.  Multiply that by two and you can see how it can get tricky. I model things the best I can in 3D but when it comes to something like this I find a hands on approach leads to a more satisfactory result. 

 

Machined of the small gear from the KA24 idler.

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I'm using a 5C expanding mandrel that I machined to fit. 

 

Test fitting the Honda exhaust cam gear that I machined previously.

 

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Happy with the fit for sure.

 

 

Quick test fit with the first idler sub plate. Looks good but I know from experience that there is a really long road from this point to the final fitting.

 

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Here are the finalish mockup sub plates for the idler gear and the tensioner arm pivot. I may move the idler up another .010" but I haven't decided.

 

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I do the majority of my prototyping in plastic. Easier to work with than aluminum and a lot cheaper. The idler plate will be steel and the pivot plate will be aluminum.

 

Upper tensioner mount.

 

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The semi finished layout.

 

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Upper tensioner is from a Mazda 626. Hybridz member Tioga turned me on to this one . I reshaped the contact shoe a bit and slapped it on there. It is a ratcheting style. They can be problematic if the lobe design on the cams are crappy. The constant pumping on the chain can break the pawls. I'm making the assumption at this point the Schneiders lobe design is a lot better than Cranes and won't be a problem. I had to reshape the contact shoe and will probably work it some more if I stick with it.

 

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Tight fit but the bottom line is....It fits. Which is a good thing since I committed to the cams before I knew for sure.  Unfortunately I can't access the VCT oil ports on the head because the idler gear is covering them but I already designed a manifold as a work around.

 

So if the pictures make it look like this was a walk in the park here is a shot of the different versions of the sub plates I made to get the relationship between all those moving components the way I wanted them as well as fitting in the space I had to work with.

 

20180526100808-8b0f7ef1-me.jpg

 

I picked the wrong time to quit sniffing glue:)

 

 

 

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Derek,   I came to the L6 forum looking for tips on updating an L28 during rebuild and what did I find?  THIS!  This is amazing, I just read all 50 pages of this, and this has been a fantastic thread. I'll definitely keep watching. The 3D sand printing is intriguing, and seems to have great resolution.  You know I love 3D printing, and I understand what a big job this has been  The Fact that v1 lasted a good long time was great! I look forward to hearing how V2 and V3 (+VTC) will work out. you've got a lot of great partners that realize how amazing this is.  I won't be able to afford one of these for some time, if ever, but I would bet they'll hold their value well! Hopefully next time I'm in FL I can come by and see your shop!

 

Question though,  How did you figure the cam profile for 6 cylinders vs the Honda 4cy? Is it based on any existing L6 cam, or fully custom, derived from L28 cams?   I will keep watching this thread and lurk your Datsunworks site.  Amazing work! 

 

Phar

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Hi Phar

2 hours ago, Pharaohabq said:

and what did I find?  THIS! 

 

Took you long enough:)

2 hours ago, Pharaohabq said:

The 3D sand printing is intriguing, and seems to have great resolution

 

It truly is an amazing process. It opens up so many things to be produced that would not have been practical before.

2 hours ago, Pharaohabq said:

Question though,  How did you figure the cam profile for 6 cylinders vs the Honda 4cy? Is it based on any existing L6 cam, or fully custom, derived from L28 cams?

 

The profile that I machine into the cams are oversized based on a Schneider profile. At that point any cam grinder with a Honda profile can finish them off. The lobe is large enough for most builds. It's S7 which means it's through hardened so you are not restricted by case thickness. 

2 hours ago, Pharaohabq said:

I will keep watching this thread and lurk your Datsunworks site

 

Yea the VCT should be pretty interesting. I'm starting a pool for how many valves I bend before I get it all sorted:)  

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8 hours ago, texis30O said:

Is this a v2 or v3 head?  Robello not doing the build on the head?

 

This is a production head or V4. I now refer to the production heads by their serial number.   S/N005  is being assembled buy the person who bought it. He chose Xtreme  to do the head work and so far I think he chose wisely. They take raw Porsche head castings and bring them all the way to a finished product so I felt comfortable with them doing the work. They also have experience with the K20. I'm hoping they become an option for people who can't wait on Rebello or like S/N005 want's to do their own build. I'm assuming they will flow the head so they will have good data for people that want to go that route. 

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On 6/2/2018 at 5:46 AM, Derek said:

 

This is a production head or V4. I now refer to the production heads by their serial number.   S/N005  is being assembled buy the person who bought it. He chose Xtreme  to do the head work and so far I think he chose wisely. They take raw Porsche head castings and bring them all the way to a finished product so I felt comfortable with them doing the work. They also have experience with the K20. I'm hoping they become an option for people who can't wait on Rebello or like S/N005 want's to do their own build. I'm assuming they will flow the head so they will have good data for people that want to go that route. 

This is very interesting.....very....

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Yea hopefully it will open up some options for people. SN005 took a bullet for the team and payed for the fixtures and the programing. The tentative pricing I saw seemed pretty reasonable depending of course on the flow gains. I hand cleaned up the ports on my new head only removing the casting finish and then smoothing. I'm going to get if flowed so there will be some sort of base line.

 

 

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I am EXTREMELY happy that someone has availed of the CNC porting experience that is out there on the K20 Head, this is EXACTLY as intentioned!

The only thing remaining is for Derek to ship him a kit of Red and Blue colored expanding silicone foam to do the intake and exhaust ports once ported so he can scan them and incorporate them as a "Race Ported' option with accompanying flow expectations...

You can do this with the sand print technology.

This pleases me greatly.

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On 5/30/2018 at 6:05 PM, Pharaohabq said:

Question though,  How did you figure the cam profile for 6 cylinders vs the Honda 4cy? Is it based on any existing L6 cam, or fully custom, derived from L28 cams?   I will keep watching this thread and lurk your Datsunworks site.  Amazing work! 

 

Phar

 
You index the cam lobes for a six cylinder firing sequence, and use the Honda Profile. The CC of the cylinder is similar and it will work reasonably well out of the gate. The Rod-Stroke and piston position should come into a proper lobe design, but I forecast that the Hondas will be close enough on an 89mm bore due to strokes being almost identical that they will work without any major modification (like I've mentioned before, there was 500 hours a year on transpacific flights in Coach that I had considering a LOT of variables before deciding on the K20 as the example to emulate!)

These are symetric profiles in many cases. If you get radical with some of the assymetric cam profiles available for Hondas out there, all you need to do is specify the cam be ground for 'reverse rotation' as these cams actually spin opposite of the way they spin in the Honda application. Not an issue on symetric bumplobes, but it does matter on the  assymetric stuff.

Once on the cam grinding machine, they index for a six cylinder with the cam profile blanks  indexed...and now I'm talking out my arse due to age because I'm almost betting the old tracer profile grinders used back in the 70's and 80's are not used in the USA at these new high production shops anymore, and they have CNC lobe profiles they simply specify and then grind on a six cylinder firing order cam blank... no more metal profiles clamped in a tracer profile slot on the grinder... 

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5 hours ago, Tony D said:

The only thing remaining is for Derek to ship him a kit of Red and Blue colored expanding silicone foam to do the intake and exhaust ports once ported so he can scan them and incorporate them as a "Race Ported' option with accompanying flow expectations...

 

Nope nope nope.   Derek won't be lifting anyones port work nor will he be offering a "race version" so lets nip that right in the bud. I'm done with versions and design changes. This is the final version.

 

It's amazing how even minor changes in a design can lead to a ton of extra work in downstream operations.

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This is so amazing...   I can't wait to hear the next version run.  Which will make it first?  The #0005 or the VCT head.  #0005 sounds like they're going to do an amazing job. Have they contacted you for consultation?   I wonder what their CR will end up with after all that work.  What will your CR be with the VCT head? Will you require higher octane?  Lastly what engine control are you going to use? Does Megasquirt handle VCT, or is this an oil pressure thing? 

 

So... stupid numbers, but a turnkey bolt on head complete might run how much $$$$???  Are you relying only on Rebello or another distributor or could we buy one straight from Datsunworks Complete?  Sorry I haven't checked your site yet.

 

Phar

 

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Hi Phar

On 6/28/2018 at 1:04 AM, Pharaohabq said:

This is so amazing... 

 

Thanks

 

On 6/28/2018 at 1:04 AM, Pharaohabq said:

I can't wait to hear the next version run.  Which will make it first?  The #0005 or the VCT head.  #0005 sounds like they're going to do an amazing job. Have they contacted you for consultation?

Probably the VCT version will be running first since I have a running motor in a car to put the head on.

 

On 6/28/2018 at 1:04 AM, Pharaohabq said:

I wonder what their CR will end up with after all that work.  What will your CR be with the VCT head? Will you require higher octane? 

 

Not sure what they will end up with. I'm planning on 11.5:1 on mine which will easily run pump gas. But that won't happen until I build my stroker.  I'm helping SN005 with things directly related to the head but as far as engine building they know more than I do for sure. Xtreme is only doing the head machine work the owner is doing the rest of the build himself.

 

On 6/28/2018 at 1:04 AM, Pharaohabq said:

Does Megasquirt handle VCT, or is this an oil pressure thing

I'm going to be running MS3 as it's required for the VCT. It uses pulse width modulation to vary an oil valve to the phaser and a sensor on the crank and intake cam to determine position. Jeff at Linfert Performance is handling all things ECU and VCT for me. He is doing SN005 as well. It is non VCT and running a MS3 and using Jenevy Heritage ITBs.

 

On 6/28/2018 at 1:04 AM, Pharaohabq said:

So... stupid numbers, but a turnkey bolt on head complete might run how much $$$$???  Are you relying only on Rebello or another distributor or could we buy one straight from Datsunworks Complete?  Sorry I haven't checked your site yet.

 

No numbers on a turnkey head because (by design) currently no two head builds are the same. Of the three that have been sold they are very different levels. I upped the basic estimate on my  FAQ for DOHC to $14-16 K at this point. Keep in mind this is without induction or exhaust. 

On 6/28/2018 at 1:04 AM, Pharaohabq said:

Are you relying only on Rebello or another distributor or could we buy one straight from Datsunworks Complete?

 

I'm not relying on Rebello as the sole source. Xtreme Has a lot of experience with K20 heads and that directly applies to the KN20. Right now I'm being very picky about who I sell to because it is really easy to get sideways on certain aspects of this. I only sold the head to SN005 because he had lined up Xtreme already and I made him qualify with me over the phone that he had the skills to do the rest of the build.

 

I have no plans at all to offer a ready to bolt on head. 

 

 

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