I have the chance to buy a clean 91 Accord LX with a dicked up crank bolt. Of course the easiest option is to get another bottom end. Well I have to have a nice F23a Bottom end and the head on the F22a1 is still good of course. What could be the effects of having this setup and is it doable? I have looked at the F23 and seen that its pretty much the same block accept the fact that it has a bigger bore than the F22. Would I be running the 9.5:1 compression? What if I wanted to put in K24a pistons and put the F22a head on it....will the compression be too high? I am trying to get as much information as I can before I start pissing up a rope.

 

I am not sure if this is doable without a ton of work.

When you start mixing engine halves, you have to look at how they would seal. You would have to look at the cylinder head gaskets to see what differences exist.

Also, the timing belt may be different between the engines. You would have to see if the aftermarket belts for the two engines have the same part number.

If only the F23a1 crank bolt is messed up, you may be able to remove it with an ez-out. I have read where people were able to do this. It would be a pretty cheap fix if that is all that is wrong with that engine.

 

Im buying it from a 20 year Honda mechanic and if he can't fix it, then there isn't anybody going to be fixing it. I would think I would use a the F23a1 head gasket when I do it. After some research on the web I have found it has been done without mods. The little bit extra displacement and the high flowing F22a head would make the thing a monster turbo or all motor.

 

yes it can be done. I don't think your c/r will go up it should go down...don't hold me to that just yet. Since the bore is 86mm...but both heads have a 50cc dome. But the next thing to look at is the f23 crank is 97mm vs. the f22 crank is 95mm. But the f23 rod height it 5.551 vs. the f22 height its 5.572.
So might be valve clearance issues...you would need and want to clay the engine be4 actually running it. This would be a good set up since the f22a heads out flow the f23 heads. You will have a 1mm over bore than the f22 block and with more stroke. SO you should see some nice tq. numbers.
I know this swap has been done a few times look around on cb7tuner.com and google this swap also I know the info is out there. As for the timing belt they should be the same. But the f23 block should be a obd2 engine...that really shouldn’t matter but you won’t have a knock sensor anymore and another sensor that you can't use anymore but I can't remember what it is right now. As for the k20 pistons if your goin n/a compression is good the more the merrier but you don’t want to go to high b/c you will need to compensate by using race fuel. But again you will need to clay the engine and make sure there is no valve clearance issues

Read this thread - this info is GOLD

https://www.hondaaccordforum.com/for...ad.php?t=33975

 

I would get on CB7tuner but I am permabanned because of some extremely stupid rule that everybody else on there breaks every day. Plus Deev is a douchebag anyway so I am done with that forum. I cant even look at it because I am IP banned or something. Im sure a changing of my IP will fix that but its w/e.

On the lighter note, I know that the VTEC F23A1 has a 9.5:1 compression and the non-vtec ones have 8.8. The question now is if the compression ratios lie in the head or block. I have done a bunch of heavy duty research but all I can come up with is the G23 which is something I dont want to play with YET. I just want a high compression F-series that will make a built B-series look like a POS. I am already giving new Si's a run for their money but I just wanna have the power there when I want it. And god knows I NEED the extra torque because I tow a trailer with this car that weighs close to 800lbs empty.

 

compression ratio comes from a little bit of everything. Mainly it comes from your pistons. But you can bump up c/r by milling the head or decking the block also can be done by using a single layer head gasket. But the RIGHT way to gain compression is by using diff. pistons.

 

Cool deal. I think what I am going to do is buy this CB out here thats got a dicked up crank and I am going to throw the head from that motor onto this F23a and see how it runs and if it needs a tune or not. I actually can't find a set of K20 pistons to go in the thing without paying $600. If I am going to pay that much, Ill just get F23 pistons. Anybody have a good source for pistons besides Honda?

 

don’t use f23 pistons. get custom pistons for the c/r you want. try bisimoto for your pistions needs. BTW your gonna spend 500-600bucks on pistons. If you use OEM f23 pistons you won’t gain anything. C/r is WAY too low for a n/a build now they would be good for boost until you start adding tons of boost to each cyl