1969honda Posted October 18, 2015 Share Posted October 18, 2015 Looks amazing, can't wait to see how the cans and everything look! Quote Link to comment Share on other sites More sharing options...
dangerZone Posted October 18, 2015 Share Posted October 18, 2015 Are those Australian made throttle bodies? Quote Link to comment Share on other sites More sharing options...
Derek Posted October 18, 2015 Author Share Posted October 18, 2015 Are those Australian made throttle bodies? Yes I got the from EFI hardware. They are their DC&O economy brand. The quality is quite good for what I paid. Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 18, 2015 Share Posted October 18, 2015 O-Ring seal on the back of the manifold to the head? Or gasket? That Throttle Body and Trumpet almost makes me want to go N/A. Almost.... Quote Link to comment Share on other sites More sharing options...
G-E Posted October 18, 2015 Share Posted October 18, 2015 Haha! The art of tracing will never die! Looks awesome... Quote Link to comment Share on other sites More sharing options...
Derek Posted October 18, 2015 Author Share Posted October 18, 2015 O-Ring seal on the back of the manifold to the head? Or gasket? That Throttle Body and Trumpet almost makes me want to go N/A. Almost.... It's going to be O-ring. And I'm not looking forward to it. 3/32 end mill in an old Bridgeport in cast aluminum...Ugh... 5500 RPM spindle can be a little restrictive with small bits. The stacks and hardlines are going to give it exactly the look I want. Which kind of makes sense since I'm building it for me:) Haha! The art of tracing will never die! Looks awesome... I have a $20,000 white light scanner and I still use the tracing method all the time. Now though instead of a flatbed scanner I just photograph the tracing with my phone. Thanks for the compliments everyone. I'm chomping at the bit to get back at it tomorrow:) Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 18, 2015 Share Posted October 18, 2015 Some suggest a 3.4 is what you need under that head to make power at 8,000 or so.... That should make for more than enough breathing on an L28 at 9K+ Big Bores, Short Strokes, Long Rods breathe nicely! Quote Link to comment Share on other sites More sharing options...
Z-Dreamer Posted October 19, 2015 Share Posted October 19, 2015 (edited) Some suggest a 3.4 is what you need under that head to make power at 8,000 or so.... That should make for more than enough breathing on an L28 at 9K+ Big Bores, Short Strokes, Long Rods breathe nicely! Hm... How about this? L28 block bored .040 over, L24 crank, 87mm Mahle PowerPak RB30DET Pistons (32.10 pin height), 140mm FJ20 rods or aftermarket H-beams. This combination yields 2629cc's with a 1.90 Rod/Stroke ratio. The pistons will stick out the bore 1mm, but could be milled or use a 1 or 2mm head gasket. Edited October 19, 2015 by Z-Dreamer Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 19, 2015 Share Posted October 19, 2015 (edited) About three milimeters shy in bore sizing. 89 or 90.... This is not a head you want to cobble together pistons and scrap parts to assemble. The smaller engines will need a lot of Revs to make use of the breathing potential of the head. A 3.4L would be supported to 7,000+, a 3.3 to 8,000+... see the trend forming? Remember these heads were centered around a 600cc cylinder displacement... Edited October 19, 2015 by Tony D Quote Link to comment Share on other sites More sharing options...
Derek Posted October 19, 2015 Author Share Posted October 19, 2015 I think on any NA setup you are going to need custom pistons to make any kind of power. The K20 has a large combustion chamber and even ones that have been welded extensively are still 47 cc's. This is a head with a 47cc chamber done by theoldone.com I'm going to pattern the raw castings around this design since all of the chambers will get machined to order. I think from a off the shelf piston standpoint the turbo people will have a better chance. Quote Link to comment Share on other sites More sharing options...
Derek Posted October 20, 2015 Author Share Posted October 20, 2015 (edited) Making some progress. Got the manifold to head flange done. I still need to de-burr the sharp edges but I'm happy with the results. Hard to tell in this picture but the ports match really well. 1/3 of a money shot:) Should be able to finish up the other 2 tomorrow. Now If I could just get my valve cover I'd be set for a while. Edited July 7, 2017 by Derek Quote Link to comment Share on other sites More sharing options...
texis30O Posted October 21, 2015 Share Posted October 21, 2015 You are making it hard for me to decide N/A or Turbo...... I have been leaning to N/A but LOVE Big power..... Quote Link to comment Share on other sites More sharing options...
Derek Posted October 21, 2015 Author Share Posted October 21, 2015 (edited) And then there were three..... Here are some process shots for those of you that are interested. After rough surface and fly cutting. Outlining the flange. O-ring groove. Port matched and injector clearance machined in. I'll hand finish the injector area. Edited July 7, 2017 by Derek Quote Link to comment Share on other sites More sharing options...
Derek Posted October 21, 2015 Author Share Posted October 21, 2015 You are making it hard for me to decide N/A or Turbo...... I have been leaning to N/A but LOVE Big power..... Simple....Build two:) Quote Link to comment Share on other sites More sharing options...
greg Posted October 21, 2015 Share Posted October 21, 2015 Very nice job! Amazing! Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 22, 2015 Share Posted October 22, 2015 I forget the stock C Chamber size, it was fairly low given what most modify them to accomplish for N/A. The 47cc chamber is right there for a 500CC swept volume 3.0 turbo. Most of the HOMO guys are running 10:1 on their turbos, and N/A is easily run 12:1 on pump gas. Even from that perspective, an L28 with a bigdome would have better torque characteristics from the high static CR. The nice thing is the flow is achieved at relatively low lift, meaning stability at higher rpms and long valve spring life. Looks to be coming along well. Quote Link to comment Share on other sites More sharing options...
oatmilk Posted October 22, 2015 Share Posted October 22, 2015 Just wow! Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 22, 2015 Share Posted October 22, 2015 Is that a Honda O-Ring, or a generic A-XXX O-Ring going in there? Might try to see if there is an A-Series O-Ring that fits that groove acceptably, it will allow you to buy a bag for a couple of bucks and not have to buy two Four-Cylinder Kits and have two sitting around forever... Quote Link to comment Share on other sites More sharing options...
madkaw Posted October 22, 2015 Share Posted October 22, 2015 Amazing talent to put all this together. Thanks again for documenting all this for us wishers. I feel an extravagant expenditure in my future. Megasquirt is already in place. Quote Link to comment Share on other sites More sharing options...
1969honda Posted October 22, 2015 Share Posted October 22, 2015 Nissan Titan v8 has similar looking o-ring. I can get measurements if desired, I think a set is $15-20? Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.