1994-1995 Honda Accord F22B2 to F22B1 Vtec Head Swap Write Up

Before I begin please understand this swap was done as part of maintenance and a “factory like” LX to EX engine upgrade to my Wagon. Just a basic a little more HP, Torque, and MPG than it had before. Please hold any “should’ve done a DOHC swap with parts and money that fall from the sky” comments. SOHC parts are plentiful in the junkyards where I am and if that’s the same for you this swap can be pulled off pretty easy and affordably. In my area I was able to get ahold of the Vtec Ecu, Entire F22B1 engine head with the fixin’s, and matching sparkplug wires I needed for 90 US dollars. These parts were obtained from a 1994 Honda Accord EX in a junkyard. I took the used head cleaned the hell out of it, lapped the valves, and replaced the valve stem seals before starting the swap. The whole build is documented on my Youtube Channel Foxi’s Retrofitting if you need a visual instruction or more information. I will leave the “basic maintenance” items and gaskets out of this writeup that don’t apply directly to swap items. I believe swapping on a F23A1 Engine Head works generally the same except you will need the ODB1 vtec ECU and sensors. If you need information on other items it’s on my channel as well as extras like my how to on how to relocate the awfully located Accord fuel filter and other things. Now on to the swap.

vTHE PARTS LISTv

What can carry over from F22B2 Top End:

The Intake Manifold, Sparkplugs, Distributor, Cam Gear, Exhaust Manifold & Gasket, Fuel Rail, Fuel injectors (Both F22B1 & F22B2 injectors are 235 flowrate), All sensors on the engine head are the same.

Engine Head Mechanical:

F22B1 Engine Head with matching Vtec Solenoid

Vtec Valve Cover with matching bolts (If you find a nice F23 valve cover you like you can use it. (I found an Acura 2.2 cover from an Acura CL I liked)

New Vtec Valve Cover Gasket Set I used (Apex AVC 139S)

New Head Bolts (I used Mahle GS33407)

New Head Gasket (I used Fel Pro 9958PT1)

You can use your F22B2 Cam Gear as it is identical.

Engine Block:

MAKE SURE TO REMOVE THE OIL RESTRICTOR FROM THE TOP MIDDLE OF THE ENGINE BLOCK BEFORE INSTALLING THE VTEC ENGINE HEAD

This is done by threading one of the timing cover bolts into the restrictor and pulling it directly up with a pair of pliers.

Electrical:

You will need a 1994-1995 OBD1 Honda Accord EX Vtec ECU (37820-p0a-a51)

You will need some spare wire and will need to add pinned connections to A4 & D6 on the ecu harness. (A4 going to Vtec Solenoid Valve and D6 going to the Vtec Oil Pressure Sensor)

For pinned connectors I cut up an abused harness from a 2000 civic to use the pins and wire.

You can ground the ground wire coming from the Vtec Oil Pressure Sensor to the engine. I grounded mine to the thermostat housing via ring terminal.



Here’s my video showing the ECU connections along with how to run the wire to the engine bay. The pinout for what connections you are making is in the description as well.


Timing:

The Timing belt is different between F22B1 & F22B2 and will need to be swapped. (I used Beck Arnley 0260339)



Intake Manifold:

I carried over the F22B2 intake manifold from the original head. You can use either engines intake gasket set with this manifold. (I used the F22B1 Mahle MS16161 Intake Manifold gasket because it looked neater than the F22B2 gasket would.)



Ignition Coil Relocation:

The F22B2 non vtec external ignition coil will need to be relocated. Fortunately there is a tapped hole in the engine bay metal close enough to the harness so you don’t have to make an extension. I just cut the wrap back on the harness enough to allow the plug to reach the coil when relocated.



Here’s my video showing exactly where I mounted the coil:


Spark Plug Wires:

Wires for the Vtec model will have to be used. NGK 8028 or cheaper equivalent will work.

A custom plug wire to go between the distributor cap and ignition coil will have to be made. This is easily done with a cable that’s long enough to reach. Just take the sparkplug boot and lead off and restrip and crimp on a coil lead. I used a pocket knife to cut and a cheap pair of flat styled wire strippers to hold it while I cut and to crimp the lead with.



If you need to see things in more detail or would like to watch me go through the process including torque specs and maintence items like the rear motor mount, oil pressure sensor, etc you can view it on my Youtube Channel Foxi’s Retrofitting.



So now your conversion is done. The car runs and everything’s fine. What next?

After you’re done and you’ve tested everything out, congratulations you did great! If you want a little bit more of a boost to your performance you can always add an aftermarket exhaust header.

The F23A1 Intake Manifold is rumored to be slightly better. I found this information just on the basic design: The 2.3-liter Accord 4-cylinder engine intake manifold has been redesigned to add more power and lower emissions. The individual cast-aluminum runners have revised dimensions to better take advantage of the different air-flow characteristics of the 2.3-liter engine. A larger plenum chamber reduces induction noise and the incorporation of exhaust gas recirculation (EGR) ports into the plenum, upstream of the throttle plates, eliminates the need for a separate fitting and port in each intake runner. If you do this upgrade later you will need F23A4 Intake manifold gaskets and will need to convert the IACV as well. They make kits for converting the IACV if you go that route.



I hope this helps. Alot of this information is pretty sparse and I had to dig for it or figure it out myself. If anyone has any questions or need specifics on anything just ask.