l/z/ka hybrid ?s, devious?

[Xero]

i've got a z22 block, L20 crank, 152mm rods, and a dohc head in my garage that I'm going to start working on now that I'm all situated in my new place.

I've read various of devious' posts on various web forums about this hybrid, and I'm pretty sure what all I need, just got a couple questions, and I can't seem to get a hold of gabe via email.

1) lower timing chain. do you still offer the service of making a kit for the dohc head on the Z22 block?

2) timing cover. is this a full custom, or can you make the z22 lower cover work with the dohc front cover.

3) pistons. with the long rods, I'm gonna net near 12:1 with regular low-comp forged pistons for the KA, right? so getting some Arias low comp pistons will be high comp in the hybrid, I think that's what I calculated. and I'm 100% sure i'm going to have to fly cut valve clearances in them too.

thanks man, sorry if i'm uber annoying, seems your the only one who has spoken anything about what you've done

--Justin

[deviousKA]

Hey, sounds cool.

Send me an email and I can let you know a little more about the timing chain setup. gabe AT hybridka.com

Timing covers are not 'full' custom, but a little bit of work is required to mate the two, depending on which dohc cylinder head you use (240sx version the worst canditate).

With those rods and the dohc head you will need to take 1.5-2mm off the top of a standard KA piston (if you plan to use those). You need no less than .030" proximity to the deck surface of the cylinder head, or in this case, the quench area of the combustion chamber. Crushed standard gasket is approximately .040-.047" crushed depending on the manufacture, so your looking to get those pistons at just about top deck (or no more than .015" over the deck surface). With those current specs and assuming a KA piston, they will be about 1.5-2mm (.060-.080") above deck.

Flycutting/valve relief will all depend on your cam setting and durations. You could get away with a completely flat top piston sitting at exactly top deck without flycuts, if the exhaust cam is slightly advanced (assuming stock profiles). Due to the large valve size of this configuration on the 2.2l, oem 2.4l cam lift is a plenty. Because of the slow piston acceleration to and away from tdc/bdc (due to stroke and rod angles), cylinders will have a better chance to fill without extended duration.

In other words, stock KA cams work great on hybrids. You can obtain the static compression ratios you want without a whole lot of piston or head modifications, but as with any, you should be claying your pistons in the assembled engine to find out.

[Xero]

thanks Gabe, sent an email, let me know if you don't get it.

[Xero]

you get the email?

if not xerography11 at yahoo or cerenkov.170 at gmail