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Twin cam head for the L6 from Derek at Datsunworks


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I truely am excited that you are building this.  I can't wait to listen the the music from this motor on the road!


You and me both!  There is still a butt ton of stuff to do though.




Have you thought about header design yet? I wonder if just copying the primary length and diameter off a known good K series header would be a good idea. 




One of the Hybridz family is helping me out with exhaust design and fabrication. I'm sure he'll chime in at some point.



Got the intake manifold designed. I'm utilizing a balance tube like I did on my EFI manifold. It made my life a lot easier.  By doing three separate manifolds it reduces my risk of failure. I'm 3D printing the cores and I ordered them today. The pattern will be conventional. I designed the flanges to be a lot larger than I need but I want to have options when I do the machining.  I'm using the same injector boss mount as my manifold. This way I can hard line it if I want to. And I want to:) 





I got a call from the steel foundry and they are pouring the cams next week. Hopefully the first units will pass inspection. If they are good then I'll do some basic machining and then I'll ship them out to Isky for grinding.


And I'm painting my car




Base coat. 

Cleared it today.


No time to do a proper job but it's been off the road for almost two years and I had enough. I wanted to drive it again. It'll look ok. Basically painting in my fab shop so you can only imagine how clean that is:)

Edited by Derek
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Didnt you just paint it a few years ago? 


Well if December of 2007 is a few years ago then yes it "was" a few years ago:)   You're getting old. That's the first sign.

The big problem with it was I laid the base coat down too heavy and then cleared it too soon. It trapped solvents and the clear started coming off after about 4 years. I had to strip all the old clear and base off with a da. And of course there was new rust to be fixed....


That's looking awesome. What color is that red? I need to paint the Maverick red and that's a nice color.


I may need to place an order for some injector bosses...the stainless lines just look so cool....and I have a 12-injector fuel system that will need injector mounts later this year.


I use products from Southern Polyeurathanes http://www.southernpolyurethanes.com. Their products are really great (as long as you follow the directions) and the price is amazing. The red is their house brand red base. I had a little problem laying down the clear and the owner spent 20 min on the phone with me getting it dialed in.  Try that with PPG :)


Hard lines are more work but you can't beat the look IMHO.

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You know since you started this thread in September you have averaged 126 views a day? To be fair I might have been like 20 of those on a couple of the days. I usually just check the page smile, get super impressed, then leave but today I wanted to post again just to give you encouragement and kudos this is a fantastic project and even just reading it I am learning a ton. I have been thinking about a repaint for mine in the future (I painted mine in 2003ish memory is a bit fuzzy).


Good luck and I continue to look forward to your updates.

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It's my understanding that it will be an equal length header. I don't know what denotes a "long tube" from a "short tube". I do know that the large radius bends right off of the head will not be needed as the OSG head (and motor) as well as the S20 is tilted the opposite direction as ours. I don't believe that changing the tilt will be necessary on mine. This means shorter radius bends can be used and still achieve a decent length.



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Larger radius bends flow better, less restriction.

That is the purpose for using them.


Fujitsubo made a header for the non-cross flow L-Head that looks almost identical to the OSG DOHC u it...definitely a RHD Only piece...goes right through the steering shaft area on the U.S. Models.


Long gradual bends out of the head, almost to the strut tower before making a very large radius bend south to the collectors...

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Lotsa room over there now that the intake is on the other side...


Just sayin' :mrgreen:

You think JeffP isn't changing briefs and boxers regularly after going just a bit too far down the "what if" thought train? No need for an SFP Log without that inlet hanging overhead...


Not that there's anything wrong with that!

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