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Derek

Twin cam head for the L6 from Derek at Datsunworks

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Putting the finishing touches on V3. 

 

I decided to put the head back in the mill to do more work to the face. This is no easy task because I have to hang the head off of the table and rack the mill over.  Originally I was going to put the sealing o-rings in the sub plates. I realized that this would make it really difficult for someone with a manual mill to make new plates. I also determined that the idler sub plate was going to be around 6mm thick. This wasn't going to be enough meat for the bolt so I made a pocket in the head so that the plate could be thicker in that spot.  The oval holes are oil scuppers. 

 

 

 

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Oh look a pile of speaker panels on the floor:)

 

 

 

I had to offset the bolt holes on the idler to miss an oil passage. 

 

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I'm so happy with the sub plates that V2 will be going back in the mill for a modification.

 

 

 

Thanks

Derek

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Would be cool if you could fit VVT sprockets to the cams.

 

Mr Monkey you really need to pay better attention. Post #1116 clearly shows VCT being implemented.  You are receiving 1 demerit :)

 

 

Here is one of the pics to make it easier

 

 

 

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Family Portrait. 

V1 V2 V3

I snapped this before I shipped V3 to Rebello and V2 went for a visit to it's owner. Probably (hopefully) the last time they will be all together.

 

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My feeble attempt at an art shot :)
 
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Run off to the jungle to get chimps throwing crap at me through the fence, work 176 hours, and come back to find all this..

 

Things move pretty quick around these parts:)

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Since I'm planning on trying out VCT on my build I figured I'd better finalize the valving. For me it's alway a balance of (not necessarily in this order)  function, manufacturing and style. On the VCT it's always function first since what's the point if it looks better than it works.  I knew what valve I wanted to use ( manufacturing) and where it needed to go (function) but not how to make it work ( manufacturing ) and not have it be butt ugly (style).

 

I picked the valve I did because of the fact it came with it's own manifold. This makes manufacturing a lot easier since I don't have to do any precision boring. Since it's an open pressure (bleed) circuit believe I need to locate the valve as close to the cam phaser as possible to try and minimize the response lag. I also have to deliver a pretty good volume of oil at times where a fast response is necessary. 

 

I mapped out the valve with the 4 circuits. Oil in, 2 drains, advanced and retard. 

 

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The valve is a spring return and defaults to retarded cam position. Retarded seems to be the default for the phaser as well. Which makes sense.

 

Lets start with the fact that I'm not crazy style wise about hanging this valve off of the front of the timing cover. But it's the closest I can get it to the phaser and still be able to plumb it. Here is a shot of the final plumbing. Red is oil in. Light blue are the drains. brown is retard and purple is advance.

 

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Since I didn't want the valve there to begin with you can imagine how I felt when I finally gave in to the fact that I needed a .625" thick manifold block to handle all the cross drilling. I tried a bunch of scenarios but it would have added a ton of time to the machining because of doing that kind of work on a short production run casting is tough. 

 

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I also had to flip the valve 180 from my original position to get the advance and retard ports to match the head.

 

It's all about compromises in life:)

 

Derek:

 

 

 

 

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Question for you Florida peeps. I'm looking for a machine shop in central florida with a Serdi valve machine. After my problem with V1 dropping a seat I'm inclined to steer away from any shop that doesn't do seats on a regular basis or with a modern machine. Rebello is hooked up with someone but I really don't want to ship my head across the country and back if I don't have to. 

 

Thanks

Derek

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8 minutes ago, clarkspeed said:

Big Jim @ Dover Cylinder in Orlando does all our work. Best in central FL. He has a very good eye for detail that you need.  Don't know what machine he uses. 407_481_0088. Tell him you know me. 

I believe I called him and he doesn't have a Serdi.  He also seemed to take offense that I asked. Maybe I caught him at a bad time. I have a local guy here that can do it with the older style equipment. I'm really thinking about cutting the seat pockets on mine myself. I mean it's in the 4th axis and it should be more accurate than lining up via the guide. 

A tech at Ferrea told me about mixing dry ice and acetone to shrink the seats. Or I may look at nitrogen. It seems that shrinking the seats in a controlled bath would give predictable results.

My guides and seats were installed by someone who was very capable. They were just having a bad day. I'm hoping to minimize that by going with the Serdi. I may be fooling myself though.

Thanks

Derek

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On 10/14/2017 at 4:51 PM, Derek said:

A tech at Ferrea told me about mixing dry ice and acetone to shrink the seats. Or I may look at nitrogen. It seems that shrinking the seats in a controlled bath would give predictable results.

I may be misreading this, but if you mean a liquid nitrogen bath would hold temp better then dry ice and acetone, they would both hold their temperatures respectively well. We do dry ice and 200 proof ethanol to flash freeze. Use half crushed dry ice and half of the bigger pieces, the smaller pieces will super cool the ethanol as it evaporates and the bigger chunks will maintain the temperature. Until the big pieces fully evaporate you won't have any problem with maintaining a low temp. 

If you mean either liquid nitrogen or dry ice and acetone, then disregard. Although I will say if you have access to liquid nitrogen it might be cheaper, granted you would have to probably borrow a doer and container if you wanted to keep it around a while, whereas with dry ice and acetone we use a variety of containers.

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Thanks for the info.

Yes I meant either would do a good job of consistency. Seems like ethanol and dry ice would be easier to manage.  I'm going to talk to my local guy. He has the skills for sure it's just that I know the value of technology and precision and his gear is on the older side. My valve seat didn't fail due to lack of technology. It failed because of poor installation and a Serdi won't help that. 

 

Derek

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Cam core lathe work finished.

Gun drilled S7 tool steel. Eight standard and two VCT.

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My poor little lathe got quite the workout:)

These are the fronts of the VCT cams.

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I'm copying the K20 dimensions as closely as possible. For some reason they use a very shallow feed groove on the cam bearing and a much deeper groove on the phaser end.

 

Number one cam tower with the VCT grooves machined in. The drilled holes lead down to the head and the grooves will line up with the cam when I bore the towers.

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The letter C is where the intake cam will be. Although that is a coincidence as this is tower 1 set C. The next step is numbering the towers and after that they are machined as sets. I'm doing five sets this run.

 

Making progress!

Derek

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Finished machining the cam towers. I already posted some of these on my blog and facebook page but figured I'd go ahed and dump them here as well.  

First up is really the last but since is the most interesting part I figured I'd lead off with it. So from V3 forward I have been working on making sure that people who wanted to upgrade to VCT down the road wouldn't be stuck buying a whole new head. This has turned out to be pretty difficult but not impossible. Complete redesign of the valve cover and modifying the pattern, new timing cover design and pattern, modification to the front of the head and redesign of the cam towers.   Finding room to fit two oil delivery systems was the trickiest part. 

Here is a shot of two number one towers with the caps off. VCT on top and regular on the bottom. 

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The only modification to the head and cam towers to switch to VCT is to mill two channels from the 6mm holes out to the oil grooves. To be clear you will need VCT cams and all the timing and valving bits.  My opinion on VCT is still that it's probably an expensive gadget but I needed a new challenge and figured I'd see if I can make it happen. So if you are planning on a budget build I wouldn't be holding out for VCT:)

Here are some in progress pics. Regulars to this thread have seen this stuff before but people seem to like shots of me making chips.

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Thanks

Derek

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On 11/15/2017 at 5:55 PM, grannyknot said:

Love it when the manufacture clearly labels the cam and main bearing caps.

Yea I hate guesswork too.

8 hours ago, theczechone said:

I may have missed it previously, but curious to why you chose to use cam towers instead of just caps? 

It's as simple as "that's how Honda does it".  I never considered it because I don't like to change Honda's design much. Looking at it again I don't know if you could make the journals big enough to clear the lobes and not hit the tower bolts. Also it would make plumbing the VCT a little more difficult.

Interesting thought though.

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8 hours ago, Dusty said:

Laz at Mesabalancing outside Miami has a serdi last time I was in there.  Nice guy and works on quite a variety of stuff

Thanks for the info. Probably going to stick with the local guy for now. He's five minutes away and that is nice. 

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