Announcement

**cokinut** · 01-20-2005, 12:21 PM

Valves and sensors

- EGR: f22x and h23 egr�s are swapple � they use the same gasket. I�m using the F22 EGR on the H23 Intake Manifold b/c the f22 egr has the plug.

- FITV (fast idle thermo valve): It�s on the front of the upper half of the manifold on the F22, it�s right under the TB (throttle body) on the H23. You either need to reroute the coolant lines or you can completely bypass the coolant (connect the 2 lines together).

- IAT sensor (air intake temp): they are interchangeable. Mine is broken so I�m using my F22 IAT.

- Intake Air Bypass (IAB) valve body assembly: they are the same between the F22 and H23. they use the same part numbers and you need 2 gaskets if you�re taking apart the assembly.

- Starting Air Valve: use h23.

- (IACV) Idle Air Control Valve: use h23, you can bypass it if you want, you�ll have rougher idles in colder climates.

- Intake Manifold Gaskets � they are the same, that�s why we�re doing the swap

- Fuel Rail � the f22 and h23 fuel rail and injectors are interchangeable. The fuel line going into the fuel rail is on the opposite side on the h23. That�s why I�m going to use the F22 fuel rail.

- TPS (throttle position sensor) � I believe most if not all 4 cyl Honda engines use the same tps sensor. Replace if your new intake manifold tps is broken. In order to get it off, use a dremel, slot the �rivet screw� on the top, take a flat head screw driver and unscrew it. Replace old screws with a bolt � you�ll need the size M5 0.8 metric.

- Throttle Bodies: they will not fit. Different pattern.

**cokinut** · 01-20-2005, 12:22 PM

Vaccum Lines:

this view shows the IAT and the diaphragm.

- Well, out the black box on the passenger side of the car you have like 3 hoses that come out on top, # 21,20 and 24 or something, 20 and 24 go to the intake manifold (two plugs right next to each other on the back of the mani), the #21 is on the throttle body, Then a red hose goes from the big port on the throttle body to the charcoal canister, and the #3 hose goes from the charcoal canister to the bottom of the black box. FPR goes to the center port on the intake mani, little sensor thing on the drivers side of the mani goes to your intake tube.

- IAB valve actuator – you can use the IAB control box and wire it to pin A17 on the EX ecu (PT6) or you can do it like I’m doing and get a vacuum line from the nipple of the diaphragm and connect it to the nipple on the back drivers side nipple (where the IAB control box would usually go) (EDIT: Running a properly wired IAB box and a PT6 ECU is the correct and most effective way to do this... running the IAB sytsem on vacuum alone is not as effective, and should be avoided. -deev)

here's accordaffair's write up, which will help also:
http://users.adelphia.net/~hagakure962

**cokinut** · 01-20-2005, 12:22 PM

Things You should do:

EGR cleaning

- Clean out the EGR ports. It�s a TON easier cleaning out the EGR ports while the intake manifold is off of the car.
- For the H23 Intake manifold, find a drill bit (around � inch sized) and drill through each of the 6 EGR ports. It�s easier to use a center punch to get started.

- Once drilled through, get some brake parts cleaner and some compressed air and spray it in their accordingly.
- I used a dremel and a brush bit and went in their.
- Also take off the EGR valve. The port should be crusted. Use a brush or a dremel with the brush bit and go at it.
- This might take an hour or 2 depending on how fast you work.
- Lastly, I blasted each drilled port with a blast from my pressure washer. I also did the same with the EGR valve port.
- Clean The underside of the EGR vavle too as it will be crusted over.
- The ports will be clean once you can see all the way to the bottom of each port that is above each intake runner.
- 4 of the 6 ports lead into the intake runner tract thing.
- When everything is done, replace the EGR gasket with a new one and reinstall the valve.
- I plugged up each hole with some quick hardening epoxy steel. You can also tap screw in place for easier cleaning, I was just too lazy.
- Now you�re done.

**cokinut** · 01-20-2005, 12:23 PM

VIEWS
front

back

top

Comparison of F22a6 (left) and H23 (right) | thanks to hondafan81 for the pic

Here's the F22a1 (old manifold) engine shot

**cokinut** · 01-20-2005, 12:24 PM

DIRECTIONS:
Disclaimer: I�m not responsible for anything that goes wrong during your swap. These instructions may not be 100% complete and should be used as a guide and not a bible.

- Read your Haynes or Helms manual and read and visualize the removal process.
- Drain your coolant
- You will need to relieve the fuel pressure because you are going to take off the fuel rail. http://board.hondasociety.com/showth...21#post1074021 thanks to accordztech for the fuel injector seal replacement guide.

First thing I did was I raised up the car. I jacked up the front end. Make sure to have wheel chocks, jack stands, and other safety precautions. Safety first.

Next thing on the agenda was to drain the coolant. Get a bucket and place it under the drain hole on the bottom of the radiator drain hole. Go on top and remove the radiator cap and place it somewhere where you won�t lose it. Now unscrew the plug a little bit until radiator fluid starts flowing out of the drain hole. Now just wait 10-15 minutes for the system to drain. Why are we doing this? This is because coolant lines run thru your throttle body and intake manifold.

Next thing on the list is to relieve the fuel pressure because you will be removing the fuel rail and the fuel line. Do this by uncapping the gas cap. Follow Accordztech�s guide to removing the fuel rail. http://board.hondasociety.com/showth...21#post1074021 thanks to accordztech for the fuel injector seal replacement guide.

One thing you should do before unhooking everything is to label everything you�re not sure of. It�ll make it 10x easier in the end when reassembling.

Now it�s time to start unhooking everything. I�ll list what needs to be taken off and if there were any special things I needed to do.

1. Strut Bar
2. My oil catch can (you probably won�t have)
3. Intake
4. PCV valve hose
5. IACV plug (goes from your fuel injector clips)
6. IAT plug (on the side near your brake master cylinder)
7. TPS sensor plug
8. Throttle Cable & tranny cable (might not have this)
9. All vacuum lines � the red charcoal canister vacuum line that attaches to the throttle body was a biatch to take out. Again, pry with a screw driver.
10. All radiator hoses that go to the TB and thru the IACV. Now, as warning, these took a while for me to get out. What I did was got a sharp flat head screwdriver and broke the �seal� around the hoses to get them loose. Then I pried them out and I also had a handy dandy tube/hose separator which made things easier.
11. Remove fuel pressure regulator (10mm).
12. Remove Injector clips from injectors
- Now, if this is your first time taking off the clips from the injectors, it might stump you �cause it stumped me. If you look at the plastic clip that attaches around the top of the injector, you�ll see a metal clip hugging the outside of the plastic housing clip. What you�ll need to do is remove those clips out of the way so that the injectors can come out � they should come out easily.
- Follow Accordztech�s guide to removing the fuel rail. http://board.hondasociety.com/showth...21#post1074021 thanks to accordztech for the fuel injector seal replacement guide.
13. remove the ignition coil / starter thing bolted on to the water housing. The EGR plug is attached to this assembly. It should be a 12 mm bolt.
14. Now start unbolting the top half of the old f22a1 manifold. There should be I believe 5 bolts � 3 in the front and 2 near the firewall. Take off the top half and this should leave you open space.
15. Now, I forget, there will a lot of brackets attached to the manifold � I want to say perhaps 2-3. Just unbolt those.
16. Go under the car and just unbolt the one bolt that attaches the intake manifold bracket to the manifold. Not the bracket to the engine block.
17. Now unbolt the bolts that attach the intake manifold to the head. They are 12mm. The top bolts will be relatively easy to get to and I found out to my surprise that they weren�t torqued down as bad as I thought they were. You�ll notice you can reach the 3 bolts on the bottom of the manifold towards the cam gear side easy too. It�s just when you need to get the last 2 bolts that are towards the distributor side, it�s a tight squeeze and that�s no joke. What I did was use a gear head ratchet on the second one closest to the distributor side. You can access that bolt from above inbetween the intake manifold. Now for the last bolt, which was a PITA �cause this was my first time doing this, you�ll need to remove the water housing assembly held on by 3 10mm screws. You�ll notice the water housing is �stuck.� There�s a fat radiator hose that runs from the block to the housing. Just pull on it and that hose should pop out. Now you have access to the last bolt. Voila.
18. Tap the manifold with a rubber mallot to loosen it up.
19. Once you remove the manifold, there will be some coolant in there still, so just let it drip out and don�t be too worried about it.
20. Now the old intake manifold is out.

**cokinut** · 01-20-2005, 12:24 PM

Reinstalling everything.

21. You�ll need to swap out the EGR valve to the new H23 manifold. Do this first before the injectors so you�ll have room for your wrench to tighten down the EGR valve. You�ll also need a new gasket. Remove the old one with a razor blade. Mine came cleanly off with a razor, just don�t scratch up the surface. As a side note, the h23 and f22 egr�s fit each other�s manifold, but use the accords EGR as it has the correct plug for our purpose.
22. Now swap over the injectors and fuel rail. Clean the injectors with some carb cleaner. You�ll notice that the yellow tip that was in the intake manifold is crusted with carbon. Get the carb cleaner, spray it on a towel, and wipe it away. MAKE SURE NOT TO CLOG THE INJECTOR NOZZLE. REPLACE ALL INJECTOR SEALS as stated in accordztech�s injector seal replacement guide. I didn�t do this and put me behind a day. So do everything right the first time. Side note: we are using the F22 Fuel rail because the service bolt on the H23 manifold is on the wrong side and our fuel line won�t reach it. So just use the F22 because they are interchangeable.
23. I also had to change out the IAT. Don�t lose the little o-ring washer.
24. As for the TPS sensor on the throttle body, I had to use the old one on my f22 tb. You�ll notice that the sensor is �riveted� in there. You�ll need to make a slot on top of each bolt and then get a flat head screw driver and unscrew them. Voila. I�ll get to setting the tps sensor later. You may need a new tps gasket, I just reused my old one.
25. Throttle Rotor � this step may be optional. I�m not sure if this is a manual / auto thing. But the h23 Throttle rotor (TR) only had one plug for the throttle cable. My auto f22 TR had 2 plugs/holes - 1 for the throttle cable, 1 for the auto tranny cable. You�ll see what I�m saying if you get to this point. You may not have to do it.
In order to remove the rotor, you have to remove the 10mm bolt and the washer on top of the throttle rotor. Then unclip the springs. The rotor will be stuck on there, so pry it off with a screw driver. Now be careful, the TR might fly off �cause of the spring. Now just switch the throttle rotors out. One problem I encountered was that when I used the f22 TR, the butterfly for the TB didn�t close all the way. There is an adjusting screw that allows the TB butterfly plate to close all the way. I believe it�s an 8mm screw.
26. Go to back to the engine bay and remove the old intake manifold gasket. Use a razor blade and putty knife. You can also get gasket remover spray from auto zone. This process was time consuming for me (about an hour to an hour and a half) because everything was caked on there good.
27. Now life is good, I put the bottom half of the h23 (just the runners) and hand tightened the bolts just so the intake manifold would stay put.
28. make sure all wires are out of the way (tps wire, iat). Make sure you transferred everything over, yada yada yada.
29. Torque down the bolts on the manifold in a criss cross pattern to 16 ft lbs. this is a time consuming process also and am not going to lie to you.
30. Now everything is pretty reverse of removal.
31. Reconnect the water housing and MAKE SURE you reinsert that radiator house that goes from the water housing to the engine block. Bolt everything down good.
32. Bolt on the Fuel Pressure Regulator (FPR)
33. Bolt on the upper half of the intake manifold � 16 ft lbs.
34. Now hook up all the coolant lines. Now your FITV valve is under your TB instead of on the front of the IM. Just reroute the coolant lines. Same thing goes with the other pair of coolant lines that pass thru the IACV. The only that was hard for me was to get the clamps to go around the iacv � it�s a pretty tight fit. So I unbolted it and clamped it from the bottom. As for the throttle body, you may have to cut some of the existing coolant lines b/c they may be too long.

IACV VALVE radiator hose

TB radiator hoses

35. bolt back the intake manifold bracket. It fits perfectly unlike the F22a6 dual runner.
36. bolt on the starter / ignition coil.
37. replug the IAT and EGR sensors.
38. Reattach the vacuum lines. Remember to cap off unused vacuum nipples.

- Well, out the black box on the passenger side of the car you have like 3 hoses that come out on top, # 21,20 and 24 or something, 20 and 24 go to the intake manifold (two plugs right next to each other on the back of the mani), the #21 is on the throttle body, Then a red hose goes from the big port on the throttle body to the charcoal canister, and the #3 hose goes from the charcoal canister to the bottom of the black box. FPR goes to the center port on the intake mani, little sensor thing on the drivers side of the mani goes to your intake tube.

- IAB valve actuator � you can use the IAB control box and wire it to pin A17 on the EX ecu (PT6) or you can do it like I�m doing and get a vacuum line from the nipple of the diaphragm and connect it to an unused nipple.

39. reinstall all brackets removed. The H23 has the same bracket points as the F22.
40. put back the injector clip rail. Don�t forget it has 2 black 10mm bolts. Don�t over tighten it too much.
41. Bolt down the 17mm service bolt.

**cokinut** · 01-20-2005, 12:25 PM

42. If your TPS sensor is good, just keep the throttle body on, no need to tinker with it. If you need to adjust the TPS sensor, you�ll need to unbolt the throttle body. Also make sure you use a new gasket when reinstalling. Here are the directions, thanks to dutchaccord for searching for me:

- Setting the TPS

You have to use a voltmeter to set the Throttle Position Sensor, the TPS sends a voltage signal to the computer to tell it how far open the throttle is. If it isn't set properly then the TPS will send the wrong voltage to the ECU when the throttle is closed, creating a bad idle.

To fix this you need it sending the right voltage when the throttle is closed.
There will be three wires going to the TPS.

The Green one is a ground
The yellow one is constant 5V
The red one fluctuates between 0 and 5V depending on how open or closed the throttle is.

You need to connect the voltmeter to the grounding wire OR (what I did) touch the engine a ground point (such as the engine block ) and the other one to the fluctuating wire by exposing some of the wires. Loosen the screws and shift the TPS around until it gives a voltage of 0.45 Volts when the throttle is CLOSED. It doesn't matter what it says at open throttle.
side note : one person said that if that 0.45 volts does not work, then 0.32 might because that�s what his integra�s tps said at OEM specs.
The harness must be plugged into the TPS which must be attached to the TB, therefore it is much easier to do this with the TB removed.

If you need to adjust the TPS, loosen the two small bolts holding it on and turn it either way until it gives the correct voltage. Some TPS's are attached with rivets instead, in this case you will need to use a Dremel tool or similar to remove it. If there are rivets holding it it is most likely still set from the factory and will not need setting.

If you need to adjust you idle, turn the idle adjustment screw with a flat blade screwdriver. If the screw is loose you may need some silicon to hold it still like I have.

43. once that is set, put back your intake.
44. install your strut bar
45. reattach your oil catch can (if you have one like me). If not, just make sure you use the hose that goes from the pcv valve to the big nipple on the front of the intake manifold.
46. Reattach the negative side of the battery.
47. close the radiator drain plug and fill your radiator.
There is a 12mm bleeding nipple attached to the water housing, near the egr and starter. Looks like a little nipple thing. Unscrew that a little, not all the way. Fill your radiator a 50/50 mixture (use the appropriate color anti-freeze). When filling, fill until you see fluid come out of the bleeding screw/nipple/valve in a steady stream. When it does, screw it back down. Fill the coolant overflow bottle (in front of the battery in the white plastic bottle) to the max level.
48. Lower your car from the jack stands
49. turn the ignition on to the second click and listen for the fuel pump. Make sure none of the fuel is leaking.
50. Pray that your car starts and runs fine. Haha.
51. Congratulations, you�ve made it through.

final pictures
before

after

**Michalob** · 01-20-2005, 12:36 PM

Very very well written write up. I would love to do this in the future before i try and boost. please let us know how the cars runs with the better manifold. im curious on the performance gains from it! mad props once again and keep up the good work!

**accordztech** · 01-20-2005, 12:53 PM

mad props on the writeup...

thats some good shit =)

**Boost_Lee** · 01-20-2005, 01:08 PM

Great write up Les....questions...

can i use the f22a6 IACV on the h23 plenum>?
F22 TPS will work on a H23 TB correct?
When do your IAB's open?

**91AccordLX** · 01-20-2005, 03:23 PM

hey cokinut freeking awesome DIY. you made it look so easy with all the pics and what not..i have one question for ya....the red vacuum hose that conects to the charcoal canister...umm mine is unplugged, and i cant find where it connects to, what will happen if i keep it unplugged?

**cokinut** · 01-20-2005, 07:13 PM

Originally posted by 91accordexr33

Great write up Les....questions...

can i use the f22a6 IACV on the h23 plenum>?
F22 TPS will work on a H23 TB correct?
When do your IAB's open?

1. i'm not sure. haha. didn't check. sorry. i'll line them up and see when it's not too cold outside.

2. F22 TPS will work on an H23 TB. from what i know, most 4 banger honda's have the same TPS.

3. From the butt dyno, they are close on idle and i can really feel them around 3900 rpm - redline. you can also hear it.

Originally posted by 91accordlx

hey cokinut freeking awesome DIY. you made it look so easy with all the pics and what not..i have one question for ya....the red vacuum hose that conects to the charcoal canister...umm mine is unplugged, and i cant find where it connects to, what will happen if i keep it unplugged?

thanks! the red vacuum hose that connects to the charcoal canister, i believe, is for emissions. It might affect your vacuum issues, not sure. Is it unplugged at the TB or at the Canister area? either way, get it hooked up.

**SoySauceCb7** · 01-20-2005, 07:16 PM

Holy shit rep for u!!! you took mad time to right this shit up, you should of just been like slap her in LOL.

**cokinut** · 01-20-2005, 07:23 PM

i would also like to give props to accordztech and a bunch of others who have done the swap, especially accordaffairs write up. Let me say that i was hessitant to do it b/c of all the wires, fuel rail swapping, tps adjusting, etc. I was kinda intimidated. Yes, it might take some grunting, sweating, and cursing. But if you look at this project like taking apart a car model or putting together some nuts and bolts, this is exactly what it is. My pointers are just to study where everything goes and familiarize yourself with the engine and the new manifold and all shall go well.

power? So this is the question most people will ask.

is it a big power difference?
It's definately noticeable via the butt dyno and the ears. But it's nothing like forced induction or anything. there's definately more power after 3900 rpm's - prolly 5 whp or so. It sounds like a mini-dohc car now. my next step is to add a delta regrind + cam gear.

is it worth the money and time
Definately. I labored prolly a week with it (on and off b/c of school), but in the end, when the car starts with no problems, it's the best feeling around. But mind you, i encountered 3 problems that set me back - 1) not changing the injector seals after installing the intake manifold (big mistake) | 2) setting the tps sensor | 3) changing out the rotor (set me back an hour).

Now, i'm pretty sure i can gain a little bit more power if I had the IAB black box hooked since the computer controls the A/F ratio. But for right now, it feels good. And i'm surprised that the H23 manifold fits better than the F22 in terms of the mounting bracket. good job honda.

If you guys have any questions, PM, IM, email me. Oh and the F22-DOHC intake manifold should work with the F22 block as well.

Announcement

ENG: H23 Intake Manifold Swap (56K die!!!)

ENG: H23 Intake Manifold Swap (56K die!!!)

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment