High RPM KA24DE... With L20B crank

[Iceman.kcmo]

Hello, my name is Steve. For a little while now I have been researching building a KA24DE that can rev to 9k RPM. On thing that hinders that is the half counterweighted crankshaft. Now the KA comes from the L block family. I know there are differences in the crankshafts. What I need is some Exact measurements of the L20b crankshaft. I am going to put the L20b crankshaft in the KA block and give it highter RPM range. WHere can I find these Specs? Also, would it be easier to just build a KA24E with that crank?

Thanks,
Steve.

P.S. I am staying N/A with this engine. ITB and the such. I think it will be a real beast.

[icehouse]

why not just do a ca? They rev high! I once attemped putting a ka head on a L16 bottom end for that purpose, I had bigger goals though. (10k) but I was only board for a couple days then never went back to it. maybe some day.

ps I'm the true ICE haha

[510Freak]

lol the true ice ,I thought hainz owned you Beotch,or at least thats what he says,jk .

[duke]

Icehouse, I don't think that NA CA18 are very widely available, unlike a KA and l20. Iceman, I would recomend getting a few books that specialize in L motors for more specs on the crank (how to modify nissan/datsun l-series engines for one). Also, is this just a pipe dream that you are having, or have you actually looked into it? I think it would be an awesome engine.

[duke]

Also check out the sticky in the tech section with the copy of Jason Greys page. Alot of good specs.

[datzenmike]

The KA is 20mm taller than the L20B so longer rods... hmmm have to look at this tonight when I get home.

[Paul]

Why 10K? What type of racing do you plan on doing? I hear the KA is horrible after about 4500, so a high rev KA sounds really appealing. Good luck with the project, keep us informed

[zuum510]

Even with this "horrible" motor, and shot valve guides, and smoking like a school bus... my old 240sx beat a bmw M6. Its a great motor stock. I dont understand why people are always dreaming of building "frankestein" motors and reducing reliability just to say they can or did... build something thats proven. There are some pretty awesome KA-E motors making well into the 200+ territory all motor with carbs, and its pretty easy for the average do-it-yourselfer. If you want a high rev motor without caring about making good power (torque is more fun on the street than high HP), maybe you should think about building an NA SR20DE

[Paul]

Even with this "horrible" motor, and shot valve guides, and smoking like a school bus... my old 240sx beat a bmw M6.

You can prove how reliable and 'quick' they are without laying out a big fat lie like that... haha.

[zuum510]

screw you dude. I got nothing to prove to anyone by lying. Go back to honda boards. (btw it was a 1987 not the new one) I didnt piss on your post when you said you "heard" when you dont know Shhh... so stop talkin out your exhaust bung talk about soething you know.

[sleeper123]

To respond with that kind of attitude shows a lack of self control and an unwarranted attitude. Don't react like the kind of person that would hit his fender with a wrench because he cannot get the exhaust nut loose. Take a breath and give a decent and well thought out explanation that you can be happy with yourself about unless you like to lose your temper and have your blood pressure escalate to an unhealthy level.

I am by no means flaming you but if you want help from others on this board, you need to watch what you say to others out of anger. Just a little food for thought.
Sleeper123

[zuum510]

I dont come here for help, know what your talking about before you let bats out of the attic next time. 90% of the post I put on here are to help others.

[datzenmike]

The KA is 20mm taller than the L20B so longer rods... hmmm have to look at this tonight when I get home.

Using Datsun parts only, and assuming a 45 cc head chamber volume on the DE head...

L20B crank
Z24 block (89 mm bore)
Z24 or KA24 rods
KA24 pistons (2.8dish)
I get a -5.45mm below deck height, with 7.19 compression in a 2,140 cc motor... good for a turbo.
If 5.45mm longer rods, or 5.45mm taller pistons could be found the compression goes up to 8.9 but not attainable with Datsun rods and pistons.
If there are flat top KA24 pistons the compression goes up to 7.4 (not much)

OR TRY...

L20B crank in
Z22 block bored to 89mm
Z24 pistons on
late Z22 rods for
-1mm deck height, 8.32 compression and 2,140cc motor
no special parts.
substitute KA24 pistons for 9.7 compression

Boys, calm down, or no one will even look at this post.

[datzenmike]

Sorry I was not paying attention yesterday.
The KA24E and KA24DE crankshafts have a main bearing diameter of 2.3609 the L20B's is 2.1631 so a crank swap is out. Period. The rod diameters are the same though.
The L20B crank will swap into a Z20, Z22, Z24 block, so. All the previous post above will work with a Z24 block.

[Paul]

Zuum, I was trying to say it more jokingly I'm sorry you took it so harsh. You must understand, when you said your old KA ran down an M6 I thought you were talking 2007 500hp V10 M6 lol. I'm sure you would have had a laugh as well but I didn't know you were talking about an older one.

I wasn't trying to piss on your post, I wasn't trying to talk out of my exhaust bung, and I've never been a member of any Honda boards
This is a very friendly place and I love the information everybody shares. I don't want to get anybody stirred up. Sorry if I offended you.