These cranks all share the same 55mm main journal sizing and the same rod journal sizing 48mm:

H22 from 98+ 90.7mm stroke
JDM H23Vtec 95mm stroke
K20 86mm stroke
K24 TSX or ACCORD 99mm stroke
And of course F20C and F22C

All these would need the snout and keyway modified to fit the S2k. Some like the H series need the rear of the crank modified also. Modification requires welding, machining and hardening. The crank that need the least amount of modifcations would be the K series. We've done these cranks before. I used an AP2 crank for this application: BlackTrax 600hp 2.2L RSX-T Need to scroll half way down.

The rod stroke ratio of the 2.4 will only rev to about 7-7500rpms before creating too much sidewall friction/loading. This has been proven on the dyno. Torque and hp start dropping substantially. Awesome low/mid powerbands. Tire smoking torque!

I currently just bought an 06 S2k and I was driving a 98 Prelude with a stoke JDM H23Vtec. Sorry to say but the prelude is much more fun to drive compared to the S2k...until the S2k hits vtec. I have the comparison dyno chart at the shop and will post it up here on Monday!

 

[QUOTE=BlackTrax,Jul 28 2006, 11:20 PM]

 

if i wasn't such an idiot i wouldn't have to ask so many questions....


That's pretty damn high, isn't it?

 

You have to look at rod/stroke ratio in the opposite. High rod stroke ratios reduce piston to cylinder wall loading therefore allowing you to rev higher.

B16 has r/s of about 1.74
F20C has about 1.82
Indy cars have r/s ratios of over 2

Most of the other honda engines are in the 1.5-1.6 ratios. The accord/tsx/element are in the low 1.5's. If using a 2.4L crank you can help improve the r/s ratios by custom length rods and custom pistons.

 

granted the cyl head technology is different but you get the point.

red is my H23vtec prelude H23 bottom end with H22 top end
purple is my stock 06 s2k

I put the markers in the midrange so you can see the difference