KA/L-series block crankshaft specifications

[geeaj]

I was sitting on the shitter last night pinching a loaf and decided to pickup my old trusty "How to modify your Datsun OHC engine" book for some good reading....

Some interesting info:
- L20b, Z22, Z24 cranks have six 12mm flywheel bolts
- L20b cranks are fully counterweighted
- All Nissan/Datsun have the same 49.97 connecting rod journals. (now, i'm not sure what size the ka crank journals are, but they should be the same since a z24 crank is basically the same)

Stroke:

L20b - 86.0mm
Z22 - 92.0mm
Z24 - 96.0mm
KA24E(DE) - 96.0

Main Bearing Journal Diameter

KA24E(DE) - 59.942mm
Z24 - same
Z22 - same
L20b - same

So what does this mean? There seems to be tons of choice as far as building a destroked KA motor, one that can potentially rev with a sr20. How about a destroked ka running about 2.2liters with a Z22 crank? Perfect medium between sewing machine and stump puller. Don't like that, prefer to rev? Then you can put in a L20B crank (which are very cheap on the z and 510 boards) and turn the ka into a 2.0 liter buzzsaw. Being that the L20B crank is fully counterweighted, it should be very stable at high rpm.

Some food for thought, err, digestion..... <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/blush.gif" border="0" valign="absmiddle" alt=':blush:'>

[BadMoJo]

hmmmmmm, very interesting......except for the info about you on the shitter. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/crazy.gif" border="0" valign="absmiddle" alt=':crazy:'> &nbsp;Has anyone ever tried this? I think that if was actually possible a 2.2 would be a very sweet engine. I want more info on this. &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/notify.gif" border="0" valign="absmiddle" alt=':notify:'>

[wherezmytofu]

motion 2 archive <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/smile.gif" border="0" valign="absmiddle" alt=':)'> .......west? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/thumbs-up.gif" border="0" valign="absmiddle" alt=':thumbsup:'>

[geeaj]

On the flip side, I am working on compiling data for various bore/piston combinations as well. Since crank journal sizes and main bearing sizes are similiar between KA and L series, the possibilities of piston configurations are endless as well.

Please post this in the FAQ, since I am sure that many may potentially benefit from it...

Hehe, I seen another Del Sol on the way to work this morning... <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/blush.gif" border="0" valign="absmiddle" alt=':blush:'>

[Jeff240sx]

geeaj,
edit that post and include the bores of each engine.
I'm not seeing how a l22 crank could make the ka a 2.2L engine. &nbsp;Cuz with domestic iron, a 350 block with a 400 crank makes a 383cid engine.
I can see the l20 making a 2.2L with this logic, unless, the bores are the same.
And this whole ka22de makes a helluva good idea, seeing as the JUN kit for their precious SR makes it a 2.2L motor too. &nbsp;Coincidence?
Someone try this! &nbsp;Now! &nbsp;Or buy me the crank and I'll try it!
-Jeff

[S14lover]

yes ..yes ..YES...DO IT....DO IT !!!!!i must have more power ..seriously though i really hope you guys can compile some raw data on this ...this could blow the whole KA haters world apart!(insert sinister laugh) &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sly.gif" border="0" valign="absmiddle" alt=':sly:'> P.S. tofu that axl sig you got is a fucking riot it makes me laugh everytime i read it <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/hehe.gif" border="0" valign="absmiddle" alt=':hehe:'>

[sykikchimp]

This is exactly what Ace was talking about doing a while back. &nbsp;Maybe he will chime in with some extra useful info.

Isn't the KA 86mm bore? &nbsp;if so you would have a square bore storke ratio.. &nbsp;can you say 9000 rpm KA???

[TheTimanator]

I was pondering this the other day. I didn't realize that Nissan engines were so interchangebale. What is the r/s ratio of the KA24DE? w/KA crank? w/L20B crank? and w/Z22 crank? Which is the closest to the magic 1.75?

A 9000+ redline turbo RWD car would be awesome!

Edit: Anybody know what the SR r/s ratio is?

[geeaj]

KA bore size is 89mm i believe..I'll get some updated information later...

[obruT ES 41S 79&#39;]

KA has a bore of 89mm. So does the Z24.

The cranks will interchange, it's just the matter of crank journal width.

The hot bearings for the KAT are the cutdown L series Nissan Motorsport rod bearings. KA uses narrower bearings.

The rod to stroke ratio for the KA is 1.71. SR is about 1.6x IIRC. KA with the 6.7" Carillo rods and the offset piston runs a ratio of 1.74. Even better.

The original thoughts as presented by several folks from way back in the days of the 240sx amarok list. There was already discussion about the possibility of destroking the KA. Ace picked up the discussion from my discussion on FA.

[Sean1978]

did anyone ever get anywhere on this?