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Derek

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Everything posted by Derek

  1. Back in the Datsun business!

    Let me be the first Derek to welcome you back Derek. Derek
  2. This is all Tony D’s fault:) Hi everyone. Some of you know me from my DIY EFI manifold project http://forums.hybridz.org/topic/63445-making-my-own-efi-intake-the-first-casting/ Well now I’m tackling a DOHC head. Some history: I get a PM from Tony D in September of 2012 about the Goerz-Paeco DOHC L6 Head coming up for air.http://forums.hybridz.org/index.php/topic/109116-dohc-l6-was-somebody-looking-for-the-goerz-paeco-dohc-l6-head/?&gopid=1020596 Which led to a brief discussion about what would be involved in producing a head. And that was the end of it... Or so you thought. Tony and I started trading emails about the feasibility of producing it and what kind of heads we could use as a donor for the valve train. Tony suggested bringing Jeff P on board because of his work with cooling the L6 head. Tony and I kicked around RB and KA motors for a while and then Tony suggested checking out the Honda K20. Bingo. Removable cam towers, factory roller rockers and a plethora of aftermarket parts. I called one oh my clients that is big in the import drag market and procured an old K20 head. I did some quick measurements and decided that it was probably workable. And so the journey began. The idea is to use the cam towers and valve train from a K20. I grabbed a quick scan with my white light scanner of the exterior. It’s dirty because I’m only using it as a reference scan to design against. I imported the scan into my solids program and then proceed to replace the mesh with solids. Jeff provided me with a great CAD drawing of his head gasket to work from. I decided to take a module approach to model the head. I made a single cylinder complete and the copied and offset it for the other cylinders. I then pulled the solids together to create a single model. At this point I was at a standstill until I could figure out what to do about the timing chain. Jeff and I had a long conversation about pros an cons of various designs. The preference would be a single chain so I ordered up a K20 set to see if it was workable. NOPE. Lower timing gear is too small to bore out to fit the L6 crank. Back to the drawing board. I decided to give the KA set a try. I decided the Altima set would be a good choice as it’s only a single row chain up top. With the roller rockers I don’t think you need a double row. I did a rough mockup on a piece of wood mounting all the pieces. Then I machined a chunk of plastic so I could actually mount it to the block. You can see I’m trying to incorporate the KA guides and lower tensioner but that won’t happen without a new lower timing cover. Here is the lower section with stock modified L6 components. The only tricky bit is I need to remove one link from the chain. I think this is a workable solution. Now I could finish modeling the front and back of the head. Next the front timing cover. The water outlet exits the head in the front and makes a 90 degree turn through the timing cover where the thermostat housing will mount. Now the valve cover. The K20 cam towers kind of dictated the overall size but I was still able to get the styling I was looking for. I was trying to have the flavor of the S20. I’m still tweaking the design but so far I’m pretty happy. The “NISSAN” and “3000” will be machined in so they are kind of placeholders for now. After talking with Jeff about his testing on coolant flow I decided to get the most out of the 3D sand printing process as I could. I designed a water jacket that would be pretty hard to duplicate traditionally. There is a lot of surface area so hopefully there will be large improvements in cooling. Here is a nice shot of the intake and exhaust cores, water core, and upper tensioner. You can see where the cross drilling will go to supply oil to the head, tensioner and idler gear lube. There will have to be additional oil supplied to the last three cam towers as the single feed in the front won’t cut it. Here is a cross section of the head. The cut plane is through the center of one of the intake valves so the ports look a bit off. There is machine allowance on the bottom so the combustion chamber is a little larger than it will be after surfacing. Well like I said in the original Goerz-Paeco post I think this is a very viable approach to producing DOHC head. Should make for an interesting conversation. Derek Oh and one more thing. What good would a thread about casting a head be without....... / / / / / / / / / / / / / / / / / / / An actual casting. We poured this Monday and I just got these pics from the foundry today. I haven't seen the head personally but we're pretty sure it is good enough to move forward with. Still lots to do but you can't imagine how happy I am to get the first one right. As long as things proceed as planned I will be selling these. There is still a lot to figure out. I have the foundry working up some pricing for me and I'll post that as soon as I can. Thanks for looking Derek EDIT: I now have a blog about this head on my site. I'm going to continue to post here but the blog is a condensed version of what you see here. There is a FAQ on the left side bar that has a lot of data. If you are new to this build you may want to come up to speed there and then start following it here as there is a lot of great back and forth that isn't on the blog. http://www.datsunworks.com/Blog/
  3. So here is what I ended up with the o-ring so far. I made the groove tighter than I normally would for a pressure seal. This way the o-ring stays in the groove well enough to handle without it falling out. For those of you that don't know o-ring grooves are wider than the o-ring to give the seal a place to go as it crushes. The valve cover isn't exactly a high pressure seal and the method of attachment doesn't have enough oomph to pull the seal down evenly. I started out with round but it seemed like it wasn’t providing enough contact area based on the mount of torque I could apply to the valve cover. I ran a square for a bit before the head shit the bed but I’m not sure if it was better or worse. My gut feeling is better because I really increased the contact area with the square profile. Makes sense in theoryville, the land of my people.
  4. Ready for battle! Getting geared up to start machining the heads. Officially the first production run.
  5. Got the valve covers done. They are machined and somewhat finished. I've decided that since I don't know what people plan to do for finishing that I would leave the final cleanup to them or their powder coater. I sanded down all of the sand tears, Rand a DA over most of it and then ran them in the vibratory finisher. The flange is grooved for a .125" o-ring. I also machine in clearance for the cam towers and bolts. There are 2 bosses on either side of the plug hole. This is for a KN20 COP. The bosses are positioned so that you can have the plug facing forward or backwards. It's up to the end user to drill and tap accordingly. Semi action shot.
  6. After this batch things should start picking up supply wise. All of the things I control move along quite quickly. Every thing else just takes forever.
  7. I did what I did because it looked nice:) Seriously.
  8. Hi. I don't know what tower with MPI refers to. I mean I probably do but not by that name. I hope demand is still there when I actually have heads to sell. No mater either way as long as I have one:)
  9. Probably not going to happen:) Actually V2 is a one of a kind head. V3 and V4 are virtually identical except for some adjustments to gating and wall thicknesses. V2 in visually different and totally unique. He also ended up with 2 valve covers and three timing covers since they only fit that head:)
  10. Well I hope to be making them for a good long time:) HP specs are based on estimations by Rebello since there are currently no running heads. V2 hasn't even been assembled yet since he decided to retire, build a custom house and shop and put a twin cam head on his Z car all at the same time. Hopefully that will be moving along soon. V3 is moving forward but slowly since it is only a small part of a comprehensive engine/car build.
  11. Thanks. It's kind of cool having a stack of DOHC castings sitting on the floor.
  12. Santa was late but better late than never:) Went down to the foundry and pored the remaining 4 heads right before the holiday break. Went down and picked them up a couple days ago. Next stop Ohio for hot isostatic pressing.
  13. L28 head 3D scan, flow, CNC

    Decent price is the sticking point. Even if you are starting with a raw casting the amount of machining is still pretty significant. A Mazworx 2JZ billet block is $9000.00 FYI.
  14. HybridZ may be shutting down.

    I would love to see a donation bar showing how much is still needed for the year. Also whatever is causing people to not show up as a donating member needs to be fixed if it hasn't already. Derek
  15. New 370Z Category?

    I personally think it is a good idea. They are Z cars and they are doing hybrid type work. Derek
  16. EFI newb advice/question maybe ITBs?

    One thing to consider is to hire a tuner to dial it all in. I had Jeff Linfert setup and tune my DOHC with ITBs and he did it all via email. Spending a little money up front getting things setup by a pro and then learning how to tweak may save you some frustration and get you on the road a lot quicker. I would find one in your area if you want to do dyno tuning as well. Derek
  17. GUAGE CONVERSIONS/SWAPS

    Search on hybridz for speedhut gauges. I love mine.
  18. Retap oil pressure vs adapter?

    Here is one from mcmaster carr. BST NPT adapter
  19. Tuning VVT-i with megasquirt II

    The word I got from my tuner is you need a MS3 unit to control VCT. There really isn't a lot out there about VCT/VVT with mega squirt. Miata conversions seem to be the most popular.
  20. VCT cam cores are finished. Really happy to have this behind me. I had one set of S7 blanks so there was no room for error. Cross drilling VCT control circuit. Talk about butt clenching. Sounds a little crispy as the drill bit breaks through the other side. S7 tool steel is some pretty tough stuff. Finished VCT circuit. Still have to deburr the holes. Here is a video of the finish pass ending on lobe 6 and starting on lobe 2. I finish them in the firing order so I don't get confused. The noise in the background are 2 other machines that I'm coding and running at the same time so I try and keep things simple:) Next they'r off to Crane for heat treating and OD grinding.
  21. L24 Crank Damper Replacement Options

    The dual pulley is what's going to mess you up for aftermarket. Probably rebuilding your existing damper is going to be the cheapest route. FYI I sell a 36:1 kit and sensor mount. EDIS Kit for $220.00
  22. Thanks for the info. Probably going to stick with the local guy for now. He's five minutes away and that is nice.
  23. How to mount an EDIS wheel for $0.75

    Not sure what your budget is but I sell a kit that will work with some dampers. $220.00 plus shipping. EDIS Kit
  24. Yea I hate guesswork too. 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.
  25. 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. 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. Thanks Derek
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