Just got a bit disappointed, saw an Ad in Classic motorsports for OS Giken that had pics of a Z car with the very rare OS Giken DOHC crossflow head on it's L series engine and thought that maybe they were producing this vintage rare part once again. So I go to the OS Giken website and no I guess just a marketing ploy......sucks! I'm sure my Z car friends would have had similar feelings.
Chris Rummel
Man you guys are tough!
Nowhere in the ad does it say they are going to be reproducing this head. In the ad, it clearly states that they sell Close Ratio Gear Sets, Racing Clutches, and Super Lock LSDs for a variety of makes.
If they were going to start making this head again, don't you think they would announce it more prominently?
The Z car was in the ad, no doubt to pay tribute to O.S. Giken's heritage, and to remind enthusiasts that they have been in the performance world for a long, long time.
If Porsche ran an image of a 550 Spyder in an ad, would you think they were re-releasing it?
Marketing ploy? Well I guess if you are talking about it, and thinking about their company it worked. I don't see anything unscrupulous, or misleading about the ad though.
I don't see anything wrong with a company recalling it's performance history.
Besides, that thing is damn sexy!
Yeah, to call it a fakeout is probably a little harsh. It's a picture that helps show how long OS Giken has been in business. If the text suggested they had cylinder heads for those applications, I'd see your point.
Maybe they'll see this thread and get some castings made...we can dream, right?
Tom Heath wrote: Maybe they'll see this thread and get some castings made...we can dream, right?
Id offer, but thats waaaaay outa my league, but I can make wicked cool VW belt buckles lol
In all seriousness, I know people who can cast those...not sure what OSG would have to say about it, but I can put person A in touch with person B. Not sure what castings like that might run, not to mention youd need the patterns.
I apologize for being a knucklehead to a good advertiser. Hey, those advertisers allow me to buy the magazine for a cheaper rate. Do check this out.....2009 SEMA Show
http://japanesenostalgiccar.com/blog/2009/11/05/sema-2009-os-giken-tc24-b1-twin-cam-l-series-head/
No problem Pete! I didn't realize they were considering making even a limited run of those heads. Who wouldn't want a DOHC L-series!
With all the talent this board holds, who says the GRM Forum couldn't get a run of heads made for something? Something crazy, like a raised port Miata head! Or maybe a really nice head for the 2.5 BMW inliner-6 found in the E30? How exciting would that be?
i'd like to see a crossflow jeep inline 6 head.
pete240z wrote: I apologize for being a knucklehead to a good advertiser. Hey, those advertisers allow me to buy the magazine for a cheaper rate. Do check this out.....2009 SEMA Show http://japanesenostalgiccar.com/blog/2009/11/05/sema-2009-os-giken-tc24-b1-twin-cam-l-series-head/
Linked article said:
Now, nearly three decades later, they’re thinking of making another run of 10 units or so. Anyone who wants the unicorn of aftermarket Z parts can then do so for the price of a cool $30,000. Ouch!!!
Obviously with a 3D scanner and an existing casting, this would no longer be an issue, but there was a rumor that they were considering another TC24 production run some time ago, only to discover that the wood patterns had just been thrown on a top shelf in a damp warehouse, and all were split and warped beyond use. Or maybe that was a rumor about the TC16... I get my Datsun rumors confused.
I like this guy's approach- sectioning two KA24DE heads to make a DOHC 6 cyl. He's probably got far less than $30,000 in the head, you know, as long as he doesn't count machine time, and values his own time at $0/hr.
In reply to WilberM3:
I wonder if there is an off the shelf camshaft that would work with that in an SOHC arrangement, kind of like when Pontiac created their SOHC take on the Chevy inline six...
I just realized the problem with this is that it would probably require making a manifold for the thing. I might need an extra bucket of Legos for this one.
Why only 10? To keep up the mystique?
I want a slant six crossflow. Yes!
I really like OS Giken's products, but they will cost you everything from your phalanges to your scapula, as well as your coxal and lower phalanges.
I really want an LSD for my Supra, but their unit is more expensive than what I paid for my Supra....
I recall the guy merging the 2 KA24 heads, it was pretty labor intensive. Essentially they were bolted together, for cams I believe they used RB cams since the KA is basically an RB with two cylinders cut off. Since you can just use KA valve gear etc the thing to do would be to do as mentioned above. Take your bolted together head get all the machineing points off it and CNC a big block of alumninum into a bolt on head for an L series engine. Then you just have the cost of the billet and machining costs. Definatly less then $30K. This is what suprises me that has not been done. Granted it would still be expensive, but if I had a Z car I would be saving pennys to get it.......
Chris Rummel
Problem: Coolant passages. How would you CNC inside the billet to make the head cooling possible? This is why I think a casting would need to be made and machined into a final product, with internal passages for coolant (and oil but those are probably easier to deal with).
In reply to pres589:
Good question, I guess that depends on how complex the coolant passages were.......Don't know for sure
Has anyone machined and not cast a water cooled head before? You could do it with air, just get in and work the fins over, a CNC mill could do that with enough time (and forgetting about wear on the mill bit) but if you can't see a water passage on the outside, I don't understand how a mill could actually create it. They don't exactly tunnel well...
The only way I would think you could CNC a head from scratch is to split it horizontally. That way you could actually get to the cooling channels and areas and get as detailed as you want.
I bet if you left the ports on the bottom half and the cams/ oiling system on the top half it wouldn't be too bad. Certainly less then 30K.
I wonder if the best bet is to take the modified KA head and use it as a positive to make more raw castings.
~Alex
Or you could just drop an RB in and be done. Did that to my friends S30. It would just be nice to use the L-series block already there. Apparently, putting an RB into an S30 is a little frowned on in Japan......not traditional or something.
I think they send the Yakuza to castrate you or something....LOL
Chris Rummel
I'd only put an RB30 in a S30. And I own an RB20. :D
I'm sure they get a little more pissy when you export an older skyline. like the 60/70's era ones.
~Alex
Check out the bottom of the sheet. This is not the OK Giken head.
Ah then thats the S20 
Also a good engine. Lower displacement though.
Any one have any idea what the OS giken topped L24/6/8's made NA? I never really bothered to check that out.
~Alex
Jesus, how old is that ad? A Z-432 shipped to the west coast for $5500???
If I remember correctly the OS Giken head topped L-28 made ~300+ hp without too much trouble.....
The RB I swapped into my friends S30 was a RB25DET with an HKS GT2540 turbo greddy intake and a full 3 inch exhaust made over 300hp at the wheels on a dyno, so it was a nice trade off for lack of a Giken head.
By the way I documented the swap and did a wiring guide on HybridZ.
Chris Rummel
Rumnhammer wrote: how old is that ad?
Sorry I didn't mention.
Road & Track - July, 1971
Every once in a while I want to call my dad and yell at him.........."why didn't you buy at least one...."
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