Anyone know how much is involved to take the L18 or l20 to this size. Is it the ka24 crank???

I thought they use a Z series crank..I think you have to use the taller L20B block, they normally use the kidney shaped 180B head. For a reliable 2.4, you might need to buy 3 or 4 engines to get one with even bore thicknesses. Nissan sometimes didn't have very accurate castings, especially in the 80s. And some of the bore thicknesses differ, which leads to hot spots and piston/bore failure. My brothers old 2.4 got it's crank ground in Melbourne.. via SSS up in Girraween (When it was owned by Stewart Wilkins, and the engine work was done 3 doors down, towards the road). I wouldn't know where to get it done these days.

Chris

For 2.4 from an L18 (ALA GLEN BAKKER) you need the Z24 crank machined down and a 25mm steel spacer fitted to the top of the block that you bore through and fit a top lipped press in liner through.
Big bucks but fun!!!!!!!!!

What can these things do in hp and torque??

No more than any other L20B stroker, its just that in some rally car classes you need to use a particular block that came with the car.

chris,you might like to try wilkins performance at seven hills,that is graham wilkins,stewarts brother,its off abbott rd,it's unit 13/2 stanton rd seven hills,just up from costello pl.that's the road the m2 ends onto.he does all the machining for arthur jackson at the road & rally centre,& has a very good reputation.i've had lots of stuff balanced & machined by him,too,plus he straighted the cranks i've had nitrided,so i do recommend him.he also has a very dry sense of humour.the phone is 02-9674-7037. ps i think he used to be the guy 3 doors up from sss.

how much hp and torque is that compared to a works L20 out of curiosity?

Has anyone ever turboed a z24? instead of the more commonly used z18?