Diskovod

Will the F22B2 DOHC non-VTEC head (JDM) practically bolt on F20B?

PirateMcFred

The oil drains near the timing side won't line up very well on the F20B DOHC VTEC engine. Yes, it can be done but it's easier/better to bolt the F22B DOHC nonVTEC head onto any SOHC F-series block as it's a perfect fit.

Diskovod

Thanks for your answer!
Well, the F20B is F20B6 SOHC VTEC inside euro-spec '99 Accord, so that's a perfect fit? I have an F22B2 head only, partly assembled, with cams and cover. I guess all parts like timing belt should be used from F22B (lame question, but what if not).
And will the intake from F20 bolt on F22 head?
I hope to swap the head only, raise compression and port&polish it, maybe, get some cams... The car is my friend's, the head is mine.

p.s. Spent 2 or 3 hours recognizing what head I have. Luckily I have a valve cover, so soon after 2 hours of browsing JGE I found H23A and F22B2 engines having similiar valve covers and finally I checked the bore to define the head. Yup, 85 mm - F22B2.

PirateMcFred

All timing components should be taken from the DOHC F22B to swap onto the other F-series blocks.

The nonVTEC SOHC intake and exhaust manifolds should also swap just fine. The distributor will probably be different so get the F22B unit too.

The DOHC F22B head has a larger chamber than the SOHC heads and will drop compression considerably. You should look at installing higher compression forged pistons to raise the compression. If that's out of your budget then look into flat faced valves, and milling a good amount of material off the head to bump compression back up. If you mill the head you should get adjustable cam gears to put the cam timing back in the proper time.

It is less important to port the head than it is to consider a cam upgrade to suit the compression ratio. You can get a few different regrinds but if you're serious about making a good amount of nonVTEC power then look into "H23A" cams from Crower.com. You should also consider a good tuning device to adjust air fuel ratio after any significant modification.

I know about this subject since I have a 2.3 liter 11.7:1 CR version of what your suggesting. After everything was said and done I made 200whp 183wtq after tuning. None too shabby for a cheap beater engine.
https://honda-tech.com/forums/honda-prelude-4/new-frankenstein-engine-%3D-g23-f23-h23-write-up-long-56k-beware-1046336/

Diskovod

Crank timing gear also? any tensioners?

The F20B6 is VTEC SOHC... Probably I need to eliminate the VTEC. Thanks for distrubutor point.

I'm up to "square" the chambers, use flat oversize titanium valves (custom grind, so cheap) and mill the head. Will the timing get so weird by milling a mm? The cam sprockets use teeth so the timing should be the same as the belt will travel less in height, but its length and number of teeth is the same... or... am I losing something?

I think this project will be running on a budget, but thanks anyway. Probably I'll get the cams upgraded in the old school way - adding some metal and regrinding better cam profiles from stock cams.

I've read your build-up! Very good one and well written! You're the man!

Hmm, I definitely need to get rid of VTEC to swap the head. It has a usual SOHC cam sprocket, so its VTECness is only inside the head, VTEC actuators and ECU. How the VTEC is actuated? Can it be activated/de-activated (linked) on the ECU? I've never liked metal noodles under the hood.

Diskovod

up!