Tony D Posted March 25, 2015 Share Posted March 25, 2015 So what's the cost for a 3D printed plastic head? Quote Link to comment Share on other sites More sharing options...
Derek Posted March 27, 2015 Author Share Posted March 27, 2015 (edited) Made some real progress. One of the biggest fears I’ve had about the machine work was getting the valves in the right place. Lined up on the rockers at the top and centered on the ports at the bottom. The choices were coming in from the bottom or drilling in from the top. My “brain trust” and I came to the conclusion the having the valves line up on the rockers was more important than having them line up on the ports. The method that seemed to work the best was machine the combustion chamber and drill the spark plug hole. Roll the head over 180 degrees and indicate off of the spark plug bore. I then faced the top surface and drilled, tapped and reamed the dowel holes for the cam towers. I rotated the head to the angle I wanted and found the center of the rocker shaft that corresponded with the guides I was drilling. By working from the shaft I knew that would give me the best consistency. I then stripped the cam towers from the head and drilled the holes. For the test I used a 5.5mm drill. Thats the diameter of the valve stems. Despite all my measuring I couldn’t decide whether they needed to be at 25 degrees or 25.5 degrees. I started at 25 and naturally 25.5 seemed to line up a lot better. The nice thing about the printed sand is when I finally get the right data it will remain consistent from casting to casting. Now that this hurdle is behind me I’ll finish up a few more things on the mockup and hopefully be loading up the casting next week. Really happy with what I ended up with. The valves are sitting up since the chamber is mimicking the raw casting but the spacing is great. I drilled out the original 25 degree holes and plugged them. I also bumped the exhaust valves outward a bit. Hard to see but the valves line up really well on the rockers. Hope it goes this well when it's in aluminum Edited July 7, 2017 by Derek Quote Link to comment Share on other sites More sharing options...
ImNtUrBuddyGuy Posted March 27, 2015 Share Posted March 27, 2015 Derek, I just want to thank you for undertaking such a time and resource consuming task. I have never seen anything like it on any other forum. As far as the head construction goes, what are the proper steps to constructing, building, and testing these? Will Flow bench test be next? Quote Link to comment Share on other sites More sharing options...
ImNtUrBuddyGuy Posted March 27, 2015 Share Posted March 27, 2015 One more thing: which would be easier to build and more cost effective? An aluminum head or regular iron heads? Forgive me if this has been said before. Quote Link to comment Share on other sites More sharing options...
Derek Posted March 27, 2015 Author Share Posted March 27, 2015 Derek, I just want to thank you for undertaking such a time and resource consuming task. I have never seen anything like it on any other forum. As far as the head construction goes, what are the proper steps to constructing, building, and testing these? Will Flow bench test be next? Thanks This head is about longevity as opposed to power. If the opportunity avails itself I'll get it flowed. Earlier in the thread flow numbers were discussed but I can't remember them off of the top of my head. Iron would be tougher to work with and would not offer any benefits. Quote Link to comment Share on other sites More sharing options...
texis30O Posted March 27, 2015 Share Posted March 27, 2015 I am really happy to see progress. You are really setting the bar high. I will happily purchase one of these when you decide to make a production run. I will just have to build a motor around the head....... I am really interested to see what you come up with for an intake ( I would like to think you would do a ITB option. Quote Link to comment Share on other sites More sharing options...
Derek Posted March 27, 2015 Author Share Posted March 27, 2015 I am really happy to see progress. You are really setting the bar high. I will happily purchase one of these when you decide to make a production run. I will just have to build a motor around the head....... I am really interested to see what you come up with for an intake ( I would like to think you would do a ITB option. You should probably check out post#163 Quote Link to comment Share on other sites More sharing options...
texis30O Posted March 27, 2015 Share Posted March 27, 2015 Oh yeah, I forgot you bought those. Quote Link to comment Share on other sites More sharing options...
Tony D Posted March 29, 2015 Share Posted March 29, 2015 Flow Testing is basically greed speaking. The ports should flow more than 2X what a stock L28 (take your pick) head, and at least 50-75% better than the most advanced ports out there currently. Technology exists from several vendors that get this port flowing over 400CFM. The down fall to any Datsun DOHC Conversion has always been cost versus flow...and the ability of "just anybody" to get the parts to do the conversion. I believe this project addresses these concerns, Quote Link to comment Share on other sites More sharing options...
ImNtUrBuddyGuy Posted March 29, 2015 Share Posted March 29, 2015 Flow Testing is basically greed speaking. The ports should flow more than 2X what a stock L28 (take your pick) head, and at least 50-75% better than the most advanced ports out there currently. Technology exists from several vendors that get this port flowing over 400CFM. 400 CFM !! I've heard of people getting 200-210 out of very-well massaged Z heads but 400 cfm is out of this world! What are these heads getting stock? Quote Link to comment Share on other sites More sharing options...
Tony D Posted March 29, 2015 Share Posted March 29, 2015 It ate my response. On stock valves and a light port cleaning that head will flow 320cfm at 28" @ 0.500" lift. On the stock head they flow 200 CFM @ 0.250", 260 Cfm @ 0.350", 275 CFM @ 0.450", and over that they flatten out around 280/290cfm at 0.700" Best you're going to see on an L-Head Intake Side is around 220, and you will need 0.575 - 0.620" to do it. Going radical with 1mm oversize valves, removing valve guides and flow dividers you can get crazy flow numbers for NA, sized for 600cc cylinders and similar bore sizes. The idea was to not HAVE to do that work. Think about the streetability of a roller cam at 350" lift, with strong vacuum for an EFI MAP signal and those same camps being able to have timing events altered independently to work well NA OR turbo. And now...MS3 can do VVT control... Quote Link to comment Share on other sites More sharing options...
Derek Posted March 30, 2015 Author Share Posted March 30, 2015 (edited) And so it begins. I had some imperfections in the bottom of the casting that I needed to weld up. I made a light cleanup pass to make sure I got everything filled. Next is mapping out the combustion chambers to see exactly where they ended up. Castings shrink when they cool. Although there are formulas to use as guidelines it's still a bit of a guessing game. All the core sand inside makes it especially hard. So far so good! Edited July 7, 2017 by Derek Quote Link to comment Share on other sites More sharing options...
JoshuA Posted March 31, 2015 Share Posted March 31, 2015 Man, that's really exciting! The casting looks really good off the printed moulds. Buying a $10K head is off the table this year, sad to say it just isn't in the budget. It definitely goes in the bin of must have though. This year money goes into my RZs. Excellent work there Derek! Quote Link to comment Share on other sites More sharing options...
Derek Posted April 1, 2015 Author Share Posted April 1, 2015 (edited) made some progress today. Got the chambers mapped out and ran a finish pass over them. I designed the chambers to be "as cast' but I knew that was a mistake as soon as I saw the casting. Since I didn't have any machine allowance to work with I did the best I could. There are a few spots I'll have to hand work. I finished the surfacing and recut the water passages to make sure they were in the right spot. They were off a hair. Really happy with the quality of the casting so far. I engineered the gating system to prioritize the combustion chambers and bottom of the head. The metal is super clean so far. Tomorrow is head bolts and spark plug holes and hopefully decent progress on the top side. Edited July 7, 2017 by Derek 1 Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted April 1, 2015 Share Posted April 1, 2015 Man that's going to be nice... Quote Link to comment Share on other sites More sharing options...
texis30O Posted April 1, 2015 Share Posted April 1, 2015 The angels sang when I clicked on the photos..... I wonder why that is...... Quote Link to comment Share on other sites More sharing options...
dangerZone Posted April 1, 2015 Share Posted April 1, 2015 Would it be possible to buy 3D printed plastic ones to hang up? Or to help shape exhaust manifolds and the like for other Nissans with L engines. Quote Link to comment Share on other sites More sharing options...
Clive Posted April 1, 2015 Share Posted April 1, 2015 Sorry, have gone through all the pages and can only like it once a day it seems - needs far more! Great work and effort and keep doing what we can only imagine. Any chance of removing two cylinders to open it up to a larger public? Quote Link to comment Share on other sites More sharing options...
ImNtUrBuddyGuy Posted April 1, 2015 Share Posted April 1, 2015 Sorry, have gone through all the pages and can only like it once a day it seems - needs far more! Great work and effort and keep doing what we can only imagine. Any chance of removing two cylinders to open it up to a larger public? The head is based off a Honda K20 4 cylinder head. Of course it's being modified to fit a L series engine. Quote Link to comment Share on other sites More sharing options...
Sovereign Z Posted April 1, 2015 Share Posted April 1, 2015 I'm working my ass off this year to be able to afford one of these. I'm not sure it will happen but this is legendary Quote Link to comment Share on other sites More sharing options...
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