Announcement

Collapse
1 of 2 < >

ANY BUYING/SELLING IN THIS FORUM WILL RESULT IN AN INSTANT BAN!

Read the rules: http://www.cb7tuner.com/vbb/showthread.php?t=43956

Myself, and the other mods have been very nice and lenient with the rules. We have been deleting threads, and giving out warnings. Some members didn't get the clue and re-posted over and over... Now ANY member buying or selling in this section will be banned... No IF's AND's or BUT's.
2 of 2 < >

Beginner Forum Rules - EVERYBODY read! (old and new members alike!)

Beginners start here. Once you have 30 worthwhile posts (off topic doesn't count) you may post outside of the Beginner forums. Any "whoring" (posting simply to raise your post count) will return your count to 0, or result in a ban.

These are the rules. Read them. Live by them.

1) Absolutely NO flaming! "Flaming" is an outright attack on a member. ALL questions are encouraged to be asked here, no matter how basic. Members with over 30 posts will be subject to a ONE WEEK ban if caught flaming in this forum (and yes, moderators can read deleted posts). Members with under 30 posts will be subject to a ONE DAY ban.

2) Use appropriate language. Racial or sexual slurs will not be tolerated. A ban will be issued at the discretion of the cb7tuner.com staff.

3) No items may be sold in the Beginner forums. Any "for sale" threads will be deleted.

4) Temporarily banned members will be PERMANTLY banned if they are found posting on another account.

The rules can and will be added to. Any updates will be marked in the title.

The rules for the overall forum can be found here:
http://www.cb7tuner.com/vbb/forumdisplay.php?f=144
Read them. You will be expected to follow them.
See more
See less

F22B/H23 head vs F22A?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    F22B/H23 head vs F22A?

    I've seen others swap F22B and H23 DOHC heads on there F22A blocks. Is there is significant power increase in doing so? I've heard the SOHC F22A actually flows better than most other Honda DOHC's

    #2
    The F22A head flows very well when properly ported. Stock, it’s not all that special.

    The F22B DOHC head is the most direct and reliable head swap option, and should be good for maybe 15hp over the F22A6. That’s with the proper ecu and manifolds to go with it. The F22B DOHC has higher compression than the F22A (9.3:1 vs 8.8:1), though im not sure if that increase comes from the head, pistons, or a combination of the two. If the pistons are the same as those in the F22A, then the gain will be closer to 20hp.






    Comment


      #3
      The increase in compression between the F22A/F22B DOHC is the piston. From what I have seen the H23A1 Non VTEC, F22A1-6 and F22B DOHC, F22B1-2 combustion chambers are the same volume. it is only the VTEC P13 & P5M heads that have a smaller combustion chamber.


      As far as flow goes, the F22B1-2 and F23A1-5 castings flow better out of the box than any of the DOHC versions. The PT3 F22A1-6 head casting flows just shy of the aforementioned SOHC F series heads. Minor porting is required in order for it to easily outflow the SOHC F22B series heads. The only real bonus to the DOHC is the ability to adjust the intake and exhaust cams individually. That being said, there are SOHC camsharf grinds that can be suited to whatever goals you are looking to achieve.

      What are your goals, maximum cylinder head port CFM, actual power or a low budget build with the best out of the box head?
      MR Thread
      GhostAccord 2.4L Blog

      by Chappy, on Flickr

      Comment


        #4
        Originally posted by GhostAccord View Post
        What are your goals, maximum cylinder head port CFM, actual power or a low budget build with the best out of the box head?
        Yeah, that last one lol. Mild N/A set up, daily driven, MAYBE ITB's. Was thinking about just shaving the head for more comp. but unsure how much could be taken off before things like quench area become a issue. Would rather not rip into the block to upgrade pistons as I know once I'm in there I'll start replacing everything, and need to keep things in budget

        Comment


          #5
          In that case the F22B DOHC would probably be your best bet. Same combustion chamber diameter so there would be no issues with a lip around the head. The Honda shop manual states 0.2mm (0.008) for the limit of head surfacing. That would only get you from 8.8:1 to 8.9:1 compression ratio. You would have to remove 1.62mm (0.064) to bump the compression up to 10:1.

          I'm sure you can do more than the Honda specified 0.2mm and get away with it. However, I've never tried myself so I'm not one to speak on specifics on how far you can go before you start messing with clearance issues. I'm sure someone else could chime in on that.
          MR Thread
          GhostAccord 2.4L Blog

          by Chappy, on Flickr

          Comment


            #6
            Looks like thats the head I'll be going with then. Now to figure out if I want to hassle with ITB's...

            Comment


              #7
              Originally posted by CB7Xhris View Post
              Looks like thats the head I'll be going with then. Now to figure out if I want to hassle with ITB's...

              For a daily driver it would probably be more trouble than it's worth. It takes a GOOD tuner to make them work correctly and for a mild setup as you described it wouldn't even take full advantage of them. A single plenum manifold is better for drivability and it is easier to work with both in tuning and in related parts.

              Comment


                #8
                Originally posted by deevergote View Post
                The F22A head flows very well when properly ported. Stock, it’s not all that special.
                Well actually, I would not be so sure. I have messed around the F22A stock head in 3D CAD and the impression I have so far is that the cam is the reason why F22A is not that special stock. The head flows remarkably well even stock. Just clean out the rough casting debris and it flows a lot better. Drop in bigger valves with proper seat work and it will outflow anything. Of course, this is all theoretical and some will argue that in real life it's different. I will not go any further as my own head is still in preparation and will be for a good while since my pockets are only so deep.

                What seems interesting to me is that at least visually, the PT3 F22A and F22B DOHC non-vtec ports look nearly identical. I wonder if they have used the same casting components...

                Comment


                  #9
                  Originally posted by GhostAccord View Post
                  The only real bonus to the DOHC is the ability to adjust the intake and exhaust cams individually.
                  Ghost, I always find it funny how people claim DOHC is so much superior and only mention this specific property ... The funny fact is that DOHC lovers practically never adjust their cams at all. I only know one guy that adjusts his cams here locally, he happens to be a moto-GP rider and has all the dial indicators for the job. Still people do not realize it takes adjustable gears to do that. In my opinion the only real advantage for average people is the looks while they pop the hood. For engineers - it's a different story. Yes, DOHC gives you better valve control, yes it decreases the requirements for valve springs. Yes it allows for all sorts of fancy mechanisms like VTEC. To be honest, DOHC is really an advantage only if you are playing serious. And even then the number of cams is not the most important thing, it's the overall geometry and design. The cam has to have a big base circle for aggressive profiles, the finger followers or tappets have to support that, the springs have to support the lift and be short enough not to push the ports down and so on. There are plenty examples where SOHC performs just as well even in hardcore racing environment. Take the Honda CRF MX bike as example. It has never lacked the power or potential, yet it's smaller, lighter and easier to work with. It is the ignorance of dull people that demands DOHC in the market so it is being delivered whether beneficial or not.

                  Comment


                    #10
                    KBA, did you read the OP's original question? He wants the best bang for the buck out of a stock head on a budget build. Not some hardcore SOHC racing application. But thanks for the lesson on 1990's tech.
                    Last edited by GhostAccord; 04-04-2018, 06:24 PM.
                    MR Thread
                    GhostAccord 2.4L Blog

                    by Chappy, on Flickr

                    Comment


                      #11
                      Those ports....they beautiful... lol

                      Comment


                        #12
                        In order not to disrespect the OP further, my post was irrelevant, my mistake and apologies. It was by no way meant to flame on anyone.

                        Ghost, you have a PM.

                        Comment


                          #13
                          You will probably get more from the H23/F22A6 hybrid intake, a ground cam, and full exhaust. Hell you can skip the cam and run all that on a stock PT6 ECU. I had that setup back in the day and it was glorious


                          Originally posted by lordoja
                          im with you on that one bro! aint nothing beat free food and drinks any day of the week, even if its at a funeral

                          Comment


                            #14
                            Originally posted by gloryaccordy View Post
                            You will probably get more from the H23/F22A6 hybrid intake
                            More info on this? I got a lead on a H23 upper intake for cheap

                            Comment


                              #15
                              There should be something in the DIY section. You will need the EX ECU and a pin out to connect to the IM if you don't have an EX/SE from what I remember. But even on my EX I felt huge butt dyno gains from just swapping the plenum.


                              Originally posted by lordoja
                              im with you on that one bro! aint nothing beat free food and drinks any day of the week, even if its at a funeral

                              Comment

                              Working...
                              X