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Twin cam head for the L6 from Derek at Datsunworks


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39 minutes ago, grannyknot said:

Okay, I'll bite, how empty?  Superb work, I remember when you started this thread, pie in the sky we were thinking, happy to be wrong.


It has been quite the journey for sure. 


Finalizing my end of the pricing for the next four heads. Should have it tomorrow or Saturday.

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Watching with great interest. I've been saving my pennies since you mentioned the first ballpark figures, and I imagine others have as well. I didn't really want to be one of the early test subjects though, and I figured it would get old to spam the thread every day with "this is so cool, I absolutely must have one, etc" :icon54:


That being said, this is so cool and I absolutely must have one.

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Ok read em and weep.


There is still a lot of guess work since everything is setup to be a personal choice build. But these are some hard numbers for most everything in the picture above. Also just to point out the valve covers come raw aluminum and not powder coated.


All prices USD
Head, timing cover and valve cover machined. $7900.00 This is all you re required to buy from me everything else is individually priced.


These are items I offer and will have available with the heads.
Cam towers    $1250.00 for the set.

Semi finished S7 tool steel cam cores.  $ 2000.00 for the pair.
Cam tower bolts $45.00 Honda 
Cam tower shoulder bolts $40.00 Skunk Performance
Cam bolts from Honda 14115-PNA-000  12.00 pair
Cam washers from Honda 14113-PNA-003  14114-PNA-003   25.00 pair
Honda rocker shafts modification. $100.00 plus shafts. 
Honda Shafts  Currently $220.00 for 4.  
DCOE Intake manifolds $750.00  for the set.
Front sub plates for timing gear idler and upper tensioner $250.00
Martin 06p triplex sprocket un-machined. Currently $125.00 shipped to me.
Machine crank sprocket and shims $100.00
Cloyes 9-4180S Timing chain kit  $188.00-$220.00
Cloyes 9-4007 chain for tall deck $20.00
Idler gear shoulder washer washer.  $25.00
Idler gear shaft   13016-9E000   $42.47
Tensioner pivot bolt 13094-40F00  $4.58
Tension side guide rail bracket $35.00

Total $5245.00 depending on outside parts prices and options.

Total including head  $13,145

Cam lobe grind from Schneider Cams $250.00 each cam


Optional from me.
Valve cover breather and baffle $85.00
Oil Cap $65.00  Same thread as Nissan.


Stuff not pictured.


List of Honda valve train parts but no valves.


Honda Part numbers for springs, seats retainers etc.
These parts prices are from hondapartsnow.com and may a bit low since they are old.  They are hit or miss though on their stock. If they can’t locate it quickly in their US inventory they will cancel the  part. Another place I’ve been dealing with is hondapartsstore.com.  They are a little more money but are a more traditional dealership type parts house.

Valve Keeper 14781-PRB-A02  2.15 each *48 $103.20
Dished retainer - 14765-PRB-A01 2.65 each * 24 63.60
Rocker arms 14624-RAA-A00 24.34 * 12  292.08
Spring seat 14775-PCX-000 $2.29 each 55.00

These valve springs are recommended as a good choice for a lower performance type build.  They are a lot cheaper than aftermarket brands but do your own homework on this.
I will be using this combo on my build.

Yellow outer spring - 14761-PCX-003 6.82 * 24 163.68
Red inner spring - 14752-PRB-A01   5.63* 24  135.12

I get my Ferrea stuff from realstreetperformance.com but you may have a better source.
The head is sized to accept these guides:

VG1062    Ferrea Intake Valve Guide STD 
VG1064    Ferrea Exhaust Valve Guides STD 
VS1002    Ferrea Exhaust Valve Seal 
VS1003    Ferrea Intake Valve Seal 

Head work needed to be done:


Install and ream guides, Cut valve seat pockets and install seats. 

Valve job.
Surface head.

I'm trying to get a price nailed down from Bill at Extreme cylinder heads. He did SN005. but I would budget 2K including the seats.


You still need headers and induction on top of that price so don't forget that.


I had updated the pricing guess on my blog a while back from 12-14K to 14-16K.  My thoughts are you better have 16-18K before it is all said and done. I really tried my best to make a reasonably priced DOHC head and realistically there really isn't a cheap way to do this in the quantities that we are talking about.  Still cheaper than the other DOHC option though:)






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Economy of scale but it would take a very large financial commitment by someone who is an enthusiast because no investor in their right mind would tie their money up in this.  Plus a full redesign of the casting because it ins't designed to be made with traditional cores and the first thing that would need to go are the printed cores.



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I think that's a great price, and obviously anyone who buys one is supporting a fellow Z nut, so it's a good cause! Really cool that technology is enabling this kind of cottage industry, and it's no longer a case of "maybe some day Edelbrock or whoever will notice us".


One question I realize I still have: I can see how some of the parts in the "optional" list are actually optional, or can be sourced from the manufacturer directly (eg. the OEM Honda parts). But, when I scroll back through the pages and pages of R&D you did to get things like the camshafts right... I can't imagine any other viable way of making this seup work. I feel like you'd have to be NUTS to go it alone on almost any of that stuff. Am I missing something? I mean, I imagine someone with a similar skillset could duplicate all your effort and come to the same conclusion independently, but that seems risky, difficult, and slow.

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Everything except for the castings can be made by a competent machinist. Because of that I wanted to make sure that people were not forced into buying stuff they won't use. Case in point, Rebello has his own timing chain setup that he want's to see if he can incorporate into the head. I sold him blank plates for the idler and the upper tensioner. They have a milling machine in house and will modify the plates accordingly. Les Collins Racing have their own idea of how it should be and so on.


Robbie of Whitley Tune in New Zealand will at some point  be offering cams. I don't see any of this as a problem since people like Robbie, Les and Dave bring so much to the table and truth be told they have all been giving me feedback during the process. Especially Robbie. He has been my main sounding board for all things camshaft and VCT. I'll still be offering cams but I have no problem with other people offering them as well. 





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Really glad to see those names being supportive.  Nothing like having supporting hands of the most knowledgeable in the business.  Being Canadian, those price are outrageous. But if I made US dollars, after a few whiskeys I could possibly see myself making a silly purchase one evening. Your on Amazon right? Heck, I think I spent half that on my amateur built engine in my car now. I’m curious if it makes stock power. Ha

Edited by HuD 91gt
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  • 3 weeks later...

VCT bits and pieces.


Trying to get all all the incidental parts done so that when I get my head back from Xtreme I can concentrate on the final push. I’m locating the VCT valve in a different position than I had originally planed. I was unable to plumb it the way I wanted and that forced me to look at other options. I always hated the idea of hanging the valve off of the front of the timing cover. The control circuit is a little longer but I’m willing to take a chance for the sake of better looks.

Original 3D design:




Finished product:





It will hang below intake #1 and will be mostly out of sight.




Made the CPS mount for the back of the valve cover. This required a pretty major rework of the fuel distribution block and a new mounting bracket. I got really lucky with the block in that I didn’t need to start from scratch.




Tight fit!







It only took two versions of the CPS plate and fuel block brackets and one version of the VCT valve bracket. I must be getting the hang of this:)






Things should be picking up speed since the only thing holding me up is having the head back. 



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I cut them in the mill. It's a bit of a pain when doing single pieces since it's not worth making a fixture. I hold the stock in a vice but the jaws need to be longer than the cut out or things get ugly when your doing the outline and the setup suddenly looses is grip on the material. 

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  • 2 weeks later...



VCT Plumbing

Got the hardlines mostly done for the intake phaser control. Went well just tedious and time consuming.

The bottom two lines are advance and retard and the top two lines are returns. The center is the feed. They are 5/16 OD which gives me an ID that closely matches the Honda circuit.




It started off easy and then I remembered that an alternator needed to sit in there. That made things a little more interesting.




The bulkhead fittings worked out great.




I chose to use soft aluminum tubing for the interior lines. I knew routing them was going to be a bitch and I wasn’t wrong. Looks a little rough but it will work. Non of the fittings are compressed yet. I’ll lock everything down during the final assembly and then tweak everything so they have clearance.




Feeding through the caps turned out to be a better way to go than through the tower bases.




I had to redesign the EDIS coil bracket since the valve was now in the way. It’s not as hidden as it used to be but when the throttle bodies and stacks are on it should be buried pretty well.





I’m super glad I went this route with the VCT valve. The look of it is exactly what I wanted and he hard lines fit the whole theme of the build.




Lots happening over the next few weeks as I try and finish it up and get it back in the car.


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