Couple questions about the F23;

I can use Prelude pistons in this right? More specifically could I use JE H22 pistons? They are 87mm, which the F23 can handle being rebored too because they don't use the special cylinder material the H22/3 does, just iron sleeves? Will the 10.0:1 JE H22 Pistons yeild a similar compression in the F23 or will it be higher?

This won't bump the displacement up much will it....probably bring it up an actual 2300cc displacement.

Also, and I know I could search this, but would it be better to use like an older H23 tranny instead of whatever the F23 comes with? Or are the older F22 trannies better geared, or just the same?

This would be going into a 3rd gen Integra (96 to be exact). LS to be even more exact, so VTEC isn't a big deal, if the F23 Non-VTEC is cheaper so be it. But the idea of putting an H23 head might be interesting, if it flows better. Does the F23/2 VTEC head flow better than the H23 head, specifically does it make more TQ in the 2500-5500 area, or is it negligable?

Lots of questions I know, but thanks for any help....

 

About the pistons....yes if you bore out the block but then you have to consider if they're going to fit on the stock rods unless your replacing those as well. I would imagine it would raise the compression on the F23 since its only 9.3:1 stock.

Displacement...I dunno

The H23 has shorter gearing. Go w/ the F23 or F22

Haha...your gonna try and fit this in a 96 Teg? Good luck. You'd be better off just swapping in another B-series or building up the Ls block and turboing it or whatever you desire.

H23 head swap <--- don't bother

For someone who has more posts than I do I would figure you'd know this already.

 

H-series in a integra is no problem, so obviosly an F-series shouldn't be either.

I don't really know much about the F-Series, other than like displacement, and general power outputs.

Already been down the B20 road....I need more TQ

Plus an F22/3 total won't cost much more than a B20B runs for, and certainly less then a Dart block. I just want a car thats easy to drive around town....nothing extreme.


Thanks for the starter info though

The rods are something to consider, is the wristpin fairly in the same place between the H and F? If so it shouldn't be a problem.

 

hey, I'm going to be doing a similar swap.

for your tranny, I would go with the H tranny for the shorter gears. The Accord tranny gears are to long IMO.

 

Don't know about f23, but f22's have shorter rods than h22's (1.5mm). Not sure on the deck height of the h22 either, I'm assuming it's the same for f22. These are all things you have to consider. I used h22 rods (eagle), but had to have custom pistons made (CP).

 

Did you just have the Wristpin moved down?, or did you have the dome lowered to accomodate the taller rod?


If the F rods are shorter then H pistons should fit. It would lower the compression a bit though.

I was under the impression that the F and H blocks were basically the same. The difference being the F23 had a longer stroke, so it would naturally have shorter rods.

On the Crower website it lists the F22 and H23 as having the same rods (141.73mm), and the H22 as being different (143.15mm). But the F23 would need even shorter rods due to the slightly longer stroke, correct?

Could somebody measure the distance from the center of the wristpin, to the top rim of the piston on a H and F? If there the same, you could just reuse the F23 rods.

 

my cp's have the wristpins moved up to accomodate for the longer H22 rod. We also worked the dish towards 9.5:1 c/r to raise compression a tad over stock.

During the whole process, it was hard to find good solid numbers measurements. My final calculations went off of the H22 rods being 143mm and the stock F22(b2) rods as 141.5mm for a 1.5mm difference. We also went off a deck height of 220.015mm (8.662 inches) for my F22b2 block. Knowing that and the stroke, 95mm in my case, it's easy to calculate what pistons you need/will work.

Keep in mind though, these are for an F22b2 block and crank and can't guarantee other F blocks. My combo seems to work for me though. Have about 500 miles on it so far. Last time I checked, I think it was about 180 - 185psi compression across the board.

If anyone wants, I have the job number for my custom CP's.

 

Thanks,

According to this thread, the F23 rods are 5.550" (140.97mm), so basically another 0.5mm shorter.

But again it still depends on what the wristpin center to piston top distance is. If they are the same on H and F, then it shouldn't matter what size the rods are, as the pistons should be interchangable (aside from bore size)

According to Crower's page the F and H have the same size pins at least...

Anyone know the combustion chamber size difference between the F and H various models?

 

This chart only goes to 96, but might help you out...

http://denniscraig.org/pics/ac...g.php

 

I have a leftover h23 top end and i have an f23a1 bottom end so i was thinking about building one just for fun... I would recommend the h23 head.... Even though the f23 has a vtec head the dohc h23 head will flow better... you could even use an h22 head if desired... I know the f-blocks are made of iron but the reason they made h-blocks was so that they could go to an 87mm bore safely... So I'm not sure if you could bore out 1mm and still be in the iron, but I'll have to double check that... f23 has the biggest stoke of all the honda four bangers excluding the newer k24... so with a 97mm stroke and 87mm bore you be somewhere in the 2.4L range... It would be a torque monster... And just to let you know: H23 and F22's share the exact same crank and rods... The f23 uses basically the same crank except it has 55mm mains as opposed to all the Honda blocks that are pre 98' and have 50 mm mains...

 

Thanks.


I was thinking of a H23 head, simply because I'm only looking for 7K redline, and I've lived this long without VTEC . I know the H23 head dies after 5000-5500RPM, but the B18B head is just the same.

Thanks for the info.

Oh by chance can you see if the F23 head and H23 head are noticablly different as far as combustion chamber volume? If you still have the F23 head available to you though.

 

I can't find the exact numbers for the f23, but an f22 head is 50.5 cc and the h23 head is 50 cc... My guess would be that the f23 head is in that same range...

 

Thanks

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dennis &raquo;</TD></TR><TR><TD CLASS="quote">This chart only goes to 96, but might help you out...

http://denniscraig.org/pics/ac...g.php</TD></TR></TABLE>


right click save

 

if you want tourque, a more fun swap would be an h23 block with f23 crank, h23 rods and h22 type s pistons...by our calculations at accordinglydone.com, this would bump displacement up to 2.38 liters, or essentially a 2.4 liter honda, using all honda parts...

now, you have a choice with heads...you can stick with an sohc head for this swap and have shitty upper end power...or, you could use an h23 or h22 head...but remember, you are using a 97 mm stroke, so revving isn't the name of the game here...

my ideal situation would be to use an h22 head with this setup, and set vtec to engage at around 3500 rpm's (as this would be the efficency range of vtec)...you would still redline at the 6200 rpm bench mark of the f23 though...of course you would have to use a system like hondata to get the full effect of vtec with timing and all and not just the high cam lobe or else it would be pointless...

anyways, that system should yield tons of tourque, and mighty pull in a teg...

and btw, don't use an h22 tranny with an f22...the gears will be too short...i read somewhere the 5th gear tops out at around 115-120 on the f22...h23 would be the shortest i would go...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Nick H &raquo;</TD></TR><TR><TD CLASS="quote">if you want tourque, a more fun swap would be an h23 block with f23 crank, h23 rods and h22 type s pistons...by our calculations at accordinglydone.com, this would bump displacement up to 2.38 liters, or essentially a 2.4 liter honda, using all honda parts...</TD></TR></TABLE>

You can't put an f23 crank into an h23 block because h23 blocks have 50 mm mains while f23 has 55 mm mains, however you can put an f23 crank into a 98+ h22 block because it has 55 mm mains, and that is my future setup....

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Nick H &raquo;</TD></TR><TR><TD CLASS="quote">now, you have a choice with heads...you can stick with an sohc head for this swap and have shitty upper end power...or, you could use an h23 or h22 head...but remember, you are using a 97 mm stroke, so revving isn't the name of the game here...

my ideal situation would be to use an h22 head with this setup, and set vtec to engage at around 3500 rpm's (as this would be the efficency range of vtec)...you would still redline at the 6200 rpm bench mark of the f23 though...of course you would have to use a system like hondata to get the full effect of vtec with timing and all and not just the high cam lobe or else it would be pointless...</TD></TR></TABLE>

3500 rpms is way to low to set vtec on a NA motor.... The best place for vtec would be at about 47ish... On my h23 tec toruqe peaks before vtec kicks in at about 45-4600 rpms and with a 97 mm storke it might be slightly higher
anyways, that system should yield tons of tourque, and mighty pull in a teg...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sam1am26 &raquo;</TD></TR><TR><TD CLASS="quote">
3500 rpms is way to low to set vtec on a NA motor.... The best place for vtec would be at about 47ish... On my h23 tec toruqe peaks before vtec kicks in at about 45-4600 rpms and with a 97 mm storke it might be slightly higher
anyways, that system should yield tons of tourque, and mighty pull in a teg...
</TD></TR></TABLE>

with a 97 mm stroke, 3500 to 4000 would be optimal for vtec...remember, that vtec becomes efficient at higher piston speeds (thus needing to force air in/out in more plentiful volumes)...because of the longer stroke, greater piston speed is achieved at much lower rpm's...