Derek Posted July 24, 2016 Author Share Posted July 24, 2016 (edited) V2 has been with the new owner for the last few weeks. He has been cleaning up the ports. It's like a million degrees right now in central Florida so it's slow going. He did a great job as far as I'm concerned. He will finish the port match after the valve work is done. I had a couple different exhaust bolt patterns on V2 and unfortunately I loaded an old one by mistake. I caught it after the first hole and the water soluble coolant drained out of the hole. Never a good sign. The head is heat treated to T6 so I didn't want to weld them up . So there is an extra set of spot drills. NBD. I have a few holes to finish tapping and then it goes out for resin impregnation. Then it's back to me for pressure testing then off to have the valve work done. Derek Edited July 7, 2017 by Derek Quote Link to comment Share on other sites More sharing options...
Derek Posted July 24, 2016 Author Share Posted July 24, 2016 (edited) V1 was running great but needed some work for a variety of reasons. It actually stayed on a lot longer than I thought it would. I always had reservations about the way I had the timing chain guides and decided to test a new setup before I committed to V2. I'm using both the KA24 guides and pivoting the tensioner rail at the top. Excuse the dirty mockup block I'm using as I didn't have time to clean it. I also had 1mm shaved which brought the chambers to 50cc. It's back together and runs great except for some chain noise. I had to modify the timing cover for the slack side guide to clear. I can see with a flashlight that it's rubbing so that could be it. I'm going to run it for a few days and then tear it down. I hate to because it runs great. Derek Edited July 7, 2017 by Derek Quote Link to comment Share on other sites More sharing options...
Noddle Posted August 17, 2016 Share Posted August 17, 2016 anymore progress, pictures ? Quote Link to comment Share on other sites More sharing options...
Derek Posted August 17, 2016 Author Share Posted August 17, 2016 Not much going on. I pressure tested the casting before resin impregnation at 75 psi and it passed with flying colors. I still had it impregnated though. The head is in transit to the machine shop to have the valve work done. I don't have the cam cores back from Crane yet but I'm expecting them soon. They still have to go out for finished grind on the lobes. Kind of at a standstill until I get the head back. Derek 1 Quote Link to comment Share on other sites More sharing options...
Derek Posted September 8, 2016 Author Share Posted September 8, 2016 (edited) Got the V2 cam cores back from Crane. I've incorporated the thrust area into the actual cam. The Honda and V1 has a washer that bolts to the cam. This change allowed me to strengthen the front of the cam and also do away with the cam gear adapters. On the front of the cam I had 3 dowel holes drilled. The only way to adjust the cam timing on the K24 is to buy or make modified cam gears with offset dowel holes. The single dowel gives you 2.5 degrees adjustment at the crank per hole. By using three holes I was able to split that to 1.25 degrees advanced and 1.25 degrees retard. This is a big improvement over V1 with the adjustable hubs. The cam is semi finished from Crane. The lobes will be dialed in buy whomever ends up doing the final grind. Slowly but surely making progress. Edited July 7, 2017 by Derek Quote Link to comment Share on other sites More sharing options...
supernova_6969 Posted September 9, 2016 Share Posted September 9, 2016 this is a newbie question, but why does the cam have a copper-like finish? Quote Link to comment Share on other sites More sharing options...
Derek Posted September 9, 2016 Author Share Posted September 9, 2016 (edited) this is a newbie question, but why does the cam have a copper-like finish? That is copper plating. It is masking for the heat treat process. The cams are copper plated then everywhere you want hardened you grind away the copper. This keeps the inside of the cam soft and chewy Edited September 9, 2016 by Derek Quote Link to comment Share on other sites More sharing options...
supernova_6969 Posted September 9, 2016 Share Posted September 9, 2016 ok. newbie follow up. why would one prefer a softer cam? I know cams twist from the torque required to do their jobs ans that's all calculated. is it to allow this without it snapping, or is there another reason? Quote Link to comment Share on other sites More sharing options...
JavelinZ Posted September 9, 2016 Share Posted September 9, 2016 The wear surfaces are what need to be hard. Ductility and strength/hardness are a trade off. If you have ever messed with carbide milling cutters you will see the difference between how a piece of mild steel breaks versus a solid carbide cutter. A through hardened carbide cutter will cut through all kinds of stuff that is softer than the cutter. But when you apply too much force/stress to the carbide cutter (i.e. you exceeded the ultimate strength) that cutter is going to shatter into pieces without showing you any prior signs of deformation. Whereas you can bend a piece of mild steel around quite a bit before it work hardens to the point of breaking. In this case a through hardened cam is going to be so rigid that you would probably have a hard time not snapping when tightening the cam towers. It's not so much wanting it soft or hard, it is having the right material properties in the right place for the application. Having a hardened wear surface in a non wear region is a waste of time and ultimately money. If you have enough non hardened material cross section in the cam to prevent measurable deformation as the cam rotates and moves the rockers. Then why would the non wear regions need to be hardened? I may have not used some of the material mechanics terms properly (solid mechanics was a couple years ago for me) but that is the basic gist of things. Hopefully some of what I said will help you to think about it from another angle to make some sense of it. Quote Link to comment Share on other sites More sharing options...
texis30O Posted October 4, 2016 Share Posted October 4, 2016 Any updates? Quote Link to comment Share on other sites More sharing options...
Derek Posted October 4, 2016 Author Share Posted October 4, 2016 Nope. Head and cams at the machine shop. They are super busy and the new owner of the head isn't in a huge hurry so it's dragging on a bit. I'm sure they want to be really comfortable with the head before they go charging in. The word I got was they are starting on it this week. It's really amazing how long this stuff takes. Quote Link to comment Share on other sites More sharing options...
texis30O Posted October 4, 2016 Share Posted October 4, 2016 If you want to do it right..... yes it takes time. but if you want to slap something together and hope for the best.... well..... you go ahead and do that I am going to take my time..... Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 10, 2016 Share Posted October 10, 2016 Ahhh were we all to be idly rich with a budget for toys in the millions. I'm sure the guy I watched put his Vintage GT40 into the wall at Spa 6 Hours Historic three years running would not take this long on such a trivial project. Last I heard, his repair bill was just over $1.1 million each time to completely reconstruct a GT40 that went backwards into a wall at speed and broke in two... Custom DOHC Datsun Head? Pfft! Here's $100K let me know if you need more, otherwise I expect it in a month. BWAHAHAHAHAHAHAHAHA! Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 10, 2016 Share Posted October 10, 2016 I wonder if we can get that guy turned on to Datsun L's? Hmmmmm Quote Link to comment Share on other sites More sharing options...
texis30O Posted November 11, 2016 Share Posted November 11, 2016 Monthly check in...... Quote Link to comment Share on other sites More sharing options...
Derek Posted November 11, 2016 Author Share Posted November 11, 2016 Not much to report. The cams are at the grinder getting gun drilled as it was requested by the builder. The head should have the seats installed by now but I'm not sure on that. When they get the head back from having the seats installed they are going to flow it then come up with a grind. I've been paid for the head and the customer is fine with the pace of things so I don't have a ton of leverage. Quote Link to comment Share on other sites More sharing options...
texis30O Posted November 14, 2016 Share Posted November 14, 2016 Cool just figured I would check in. I now have 2 more 240z cars in my stable so I am now planning things out on my end. Just want to figure out the intake exhaust for this set up. I am torn between a N/A screamer or a Turbo big HP car ( but I already have a big hp Datsun). I might just keep it simple. Quote Link to comment Share on other sites More sharing options...
Derek Posted November 14, 2016 Author Share Posted November 14, 2016 Well V2 is a NA build and it will be making a trip to the dyno so that may help make your decision. Quote Link to comment Share on other sites More sharing options...
texis30O Posted November 14, 2016 Share Posted November 14, 2016 can you divulge what head/cam/valve combo it will have? Intake system? Long tubes? Stroker? compression? Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 15, 2016 Share Posted November 15, 2016 The Turbo Possibilities on this setup with even a short stroke L28 crank and a cleaned up bore for true-round will be something. GT42 is a very small starting point with no intake over it, top mount twins is a distinct possibility for some real big flow. Stock these ports flow near 300 cfm... at 8psi calculate your pounds-per hour and you will get an idea of power potential, and having turbos that spool at 3500 and go go go to 9000+ is one hell of a power band... As stroker just gives you more torque down low. 1 Quote Link to comment Share on other sites More sharing options...
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