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h23 throttle body

8K views 31 replies 12 participants last post by  hardwhite 
#1 ·
i've searched and haven't found anything answering my question. i've been told that the top half of the intake manifold of an h23 and h22 are the same, it's just the bottom half thats different. so this means all these performance throttle body's for h22's will also work with an h23 correct?
 
#3 ·
sweet! i was hoping it'd work. i'm thnking about doin a little h23 build. so is it the bigger the throttle body the better or is there overkill? cuz i found a 78mm one and was wondering if itd be a little too much
 
#6 ·
H22 and H23 tb's are the same, B16 and ITR and Ap1 S2000 throttles are also the same bolt pattern. F series are probably the same too, but D and most B series are different, and if any aftermarket company sells them as fitting the H, B, D, then their bolt patterns are probably slotted.

I've measured up several throttle bodies and found the above I mentioned to be the same as far as hole patterns go (relative to the bore center). I then measured the skunk2 tb I have and found a few holes to be slightly off from Honda's bolt pattern of the H22 tb. I'm guessing they are purposely offset and probably oversized to fit more than one manifold and I've seen pics where other manufacturers are doing the same so be careful.
 
#10 ·
H22 and H23 tb's are the same, B16 and ITR and Ap1 S2000 throttles are also the same bolt pattern. F series are probably the same too, but D and most B series are different, and if any aftermarket company sells them as fitting the H, B, D, then their bolt patterns are probably slotted.

I've measured up several throttle bodies and found the above I mentioned to be the same as far as hole patterns go (relative to the bore center). I then measured the skunk2 tb I have and found a few holes to be slightly off from Honda's bolt pattern of the H22 tb. I'm guessing they are purposely offset and probably oversized to fit more than one manifold and I've seen pics where other manufacturers are doing the same so be careful.
not trying to be an ass but are you saying the d and b dont interchange? because my friend has a d15 tb on his b18 and the only difference is the size. dont know if you were referring to the size when you said they were different or you were saying that they wouldnt interchange. oh and also the prelude b series TB doesnt fit a b18 so im guessing it wont fit anything else either.
 
#13 ·
wow i guess i just learned alot. but how big is the ITR throttle body? or the b16 one that'll fit? and still have't found an answer to my question on if bigger is better or too much is overkill and will decrease performance? thanks for all the replies though
 
#14 ·
I think bigger is better in most cases, depends on your setup. Might be overkill if you are stock. The important part is the size of the blade, the opening may be 78mm but what does it taper down to?? I used to run a 70mm on my stock H23vtec with great results, and I also ran a 70mm on my built motor as well. Now I'm running dual 60mm's :)

BTW the B16 is 60mm and the ITR/S2K are 62mm.
 
#17 ·
well all these throttle bodys might fit each other but the vacumm lines inside each other are diff i know that for a fact ..the h23 and h22 one u can use ..i woudlnt mix and match with any other...MAYBE all after market ones u can use on which ever cause they dont come with the idle thermal vavle under the throttle body
 
#18 ·
Yeah you are right, the B16, ITR and S2K are all obd2 tb's so they are gonna be slightly different and none of them have the fast idle (which I think is useless myself). As long as the gasket matches the tb you shoudl be ok. The S2K I know doesnt have an idle screw or the evap hose connection, I think the ITR does but I cant say for sure. The obd2 tb's also have a tb mounted MAP sensor, you can still use the stock MAP on the firewall as long as the hole on the tb is plugged (either with a blockoff or a spare sensor)

What was the combo you had problems with? My expierience with these has all been using the Euro-R manifold, however I know the S2K tb has been used on stock H22 manis with no issues so I cant see anything being wrong with the others.

Hers a pic... H22 on the left, S2000 tb on the right:

 
#20 ·
its funny though that the S2K TB has the cutout for the idle screw, but its just not there.

makes you wonder what they used that casting from
Yeah I know haha, I ended up adding it to that tb above, everything is there you just have to finish drill the small vac hole through the casting and then tap the threads for the idle screw which you can order for an H22. I also added the evap hose nipple too.
 
#21 ·
hmmm so say a 70mm on a h23 with bolt-ons? overkill? or what would a good size be?
 
#24 ·
how do they know its not the stock one if it bolts right in? do they cal in a prelude guru or something? haha
 
#26 ·
you know of any companies that do that have good rep? i don't wanna send my shit to no bullshit people
 
#28 ·
does it feel faster? lol. as in worth the 190 dollars?
 
#30 ·
correction: throttle response feels better

with a larger TB at the same throttle position more air is let in versus a smaller TB, so you're essentially opening the throttle farther on your smaller TB to get the same as your larger TB at smaller throttle plate angle.

thats why it feels faster, but a larger TB really has no effect until WOT or close to it, otherwise you're still playing with the same amount of air as the smaller TB, just at more/less throttle angle
 
#32 ·
sweet. i wanna see a dyno of a h23 before and after a bigger throttle body. guess its time to search around
 
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