| OZDAT http://ozdat.com.au/forum/ |
|
| Bore spacing on L4 versus SR http://ozdat.com.au/forum/viewtopic.php?t=30642 |
Page 2 of 2 |
| Author: | 180BSSSt [ Mon May 06, 2013 8:05 pm ] |
| Post subject: | Re: Bore spacing on L4 versus SR |
I can't remember the diameter offhand (I made mine over a year ago. Just copied the diameter and O-ring sizes from a distributor) but I'll check it tomorrow. Those blanking plugs look good. The bolt holes in the flange may not match up to those in the KA head but I'm sure you can make something to retain it if it needs it. |
|
| Author: | 180BSSSt [ Wed May 08, 2013 10:50 pm ] |
| Post subject: | Re: Bore spacing on L4 versus SR |
Diameter = 33mm. I made mine 15mm long. |
|
| Author: | Killerbee [ Thu May 09, 2013 2:34 am ] |
| Post subject: | Re: Bore spacing on L4 versus SR |
Just wanted to say how good it is to see you thinking way outside the square thing that people always refer to, but back to the start - what would the weight of an SR18 block be? There could be the chance of an extra kg or two less, a few more rev's (na of course), and matched with a KA head..... Hell, if I had some parts I would send them to you just to see what would happen. |
|
| Author: | d [ Tue May 14, 2013 2:14 pm ] |
| Post subject: | Re: Bore spacing on L4 versus SR |
180bssst - thank you for the size they have some 33mm here maybe 15mm or more in depth http://www.ebay.com.au/itm/Swirl-Flap-B ... 20d1ec8a35 Hey KillerB I thought you Kiwi guys already built an SR with KA head already by now!  you guys are always ahead of us here. |
|
| Author: | d [ Sat Jun 01, 2013 9:01 pm ] | |
| Post subject: | Re: Bore spacing on L4 versus SR | |
I still havent received the SR20DET bottom end Ive been planning to use for this project. Ive been thinking will I need to worry about the centre spacing of the L series head in terms of chamber location if Im going to 89mm bores? I think there is like 3 mm difference in the centre section of the L series which is bugger all. Same deal with the KA24DE head the gap seems even smaller. Attachment: DSCF0036.jpg [ 137.38 KiB | Viewed 3256 times ]
We researched economical ways to do this by perusing the rod dimensions from other motors. We did not want to order custom rods for cost and timing reasons so we figured we could find a rod/bearing combo that was close and work with that. We ended up settling on the rods from a Honda H22 Prelude motor. The H22 rod is 5.630” long vs the stock SR20’s length of 5.365”. This would give a stroke to rod length ratio of 1.66:1 vs the stock 1.58:1. Not a huge difference but one that we could probably find measurable results from.
http://www.motoiq.com/magazine_articles ... ngine.aspx
Here is another chart of piston displacement in bore over degrees of crank rotation, rod length being the variable. The big end of the Prelude rod was 2.008" in diameter and the pin end was 0.866", both of which are identical to the SR20's rod. The main difference was the rod width, the Prelude was 0.938” wide vs the SR20’s 0.894”. We could make the H22 rod work by narrowing each side of the rod’s big end by 0.022”. When looking at the Prelude rod bearing, we realized that its shell thickness was the same as the SR20’s and that it was narrow enough to not overhang the rod even after we machined its width thinner. In addition, the undercut radii on each end of the SR20 rod journals allowed the H22 bearing to fit into place without any interference issues. Add the fact that there are many H22 performance bearing options and we were sold on the Prelude rod. |
||
| Author: | jaypjay [ Wed Aug 12, 2015 5:47 pm ] |
| Post subject: | Re: Bore spacing on L4 versus SR |
I'm looking at possibly using the NA20 head on a z24 (or any other) bottom end with a Z series rocker cover. From what i get from it is its good for NA applications but maybe not for turbo applications due to the chamber design, I believe you would want an open chamber head to get the flow right. My question is if the combustion chamber was opened up CNC'd could this be used for turbo application and cure some of the faults of the naps Z heads (Running bigger valves / cam etc). Worst case scenario, the roller rockers could possibly be used in the Z head. For the life of me i cant seem to find any info on the NA20 and what bottom end it uses. It looks to be using the z24 bottom end from visuals. Does anyone have any info on this NA20 head and it's compatibility with the Lseries or Z series bottom ends ? Cheers |
|
| Author: | Lurch [ Fri Aug 14, 2015 8:38 pm ] |
| Post subject: | Re: Bore spacing on L4 versus SR |
![[ img ]](http://s397.photobucket.com/user/spamaster240z/media/Doctor%20Zed/MJ.gif.html)
|
|
| Author: | d [ Mon Aug 17, 2015 8:43 pm ] | |
| Post subject: | Re: Bore spacing on L4 versus SR | |
I'm looking at possibly using the NA20 head on a z24 (or any other) bottom end with a Z series rocker cover.
whats it going into?From what i get from it is its good for NA applications but maybe not for turbo applications due to the chamber design, I believe you would want an open chamber head to get the flow right. My question is if the combustion chamber was opened up CNC'd could this be used for turbo application and cure some of the faults of the naps Z heads (Running bigger valves / cam etc). Worst case scenario, the roller rockers could possibly be used in the Z head. For the life of me i cant seem to find any info on the NA20 and what bottom end it uses. It looks to be using the z24 bottom end from visuals. Does anyone have any info on this NA20 head and it's compatibility with the Lseries or Z series bottom ends ? Cheers L series chambers are like the NA20 chambers so turbo shouldnt be an issue. Unfortunately NA20 heads mainly used in Asia so China has them new for export and the Chinese ones are actually better than the Japanese ones for valve sizes and chamber finish from what can be seen from the pics and better cast. The Jap ones have been used in taxis for usually over 800,000 kms so would not bother with them unless you want issues with softness and head gaskets. All in all the NA20 head is like the super expensive crossflow LY heads but you are better off with a KA24de head, much easier to get 150hp straight off the bat with factory manifolding and efi or 20hp more with webers or carbs than factory efi and 10.5:1 compression using the right 90mm pistons. |
||
| Author: | Bluebird_U [ Wed Jun 03, 2020 9:33 pm ] |
| Post subject: | Re: Bore spacing on L4 versus SR |
 Bringing this one back - hopefully people are still around. I know where a NA20(s) is so was wondering what the CR for that is, in comparison with the NA20(p), and if any other parts could be used on an L series. Thanks
|
|
| Page 2 of 2 | All times are UTC+11:00 |
| Powered by phpBB® Forum Software © phpBB Limited https://www.phpbb.com/ |
|