So from what I've read so far on this topic, I get the impression that a H23 block with H22 head is a bad idea. Why is that. I've heard that turbocharging the H22 is not a good idea, because it is a high compressed engine? And a turbocharged H23/H22 Frankie would be pretty powerful?? Can someone clarify.

 

ive ridden and seen a supercharged 5th gen h22a prelude and it was fast i see nothing really wrong with going with a supercharger on the h22a super is very reliable and considered a bolt on part it all depends on the money time and maintance you want to spend if you turbo a motor and its done right there low maintance there to so its all up to you be orginal and i cant help you with the frank side of it though

 

biggest misconception that the h23a has such low compression.

i believe it's 9:8:1 to 10:1 for the h22a. this is negligable.

 

another big misconception is that you can make more power with turbo on a stock H23 then a stock H22

 

An H22/23 isn't really a bad idea, but it is somewhat costly and involved. It's an awesome idea for a drag setup like many have done before but for a street car daily driving would be compensated, mainly engine longevity. If it's a side project i'd reccomend it. Turbocharging an H22 isn't a bad idea either. Considering the stock 10:1 compression ratio you should be very conservative with the ammount of boost, it's safe to say don't go over 10lbs. for every day driving. If you lowered the compression to around 8:1 or 8 1/2:1 higher boost levels can be run easly. Also the rods are a concern when turbocharging. Being a lot thinner than you would expect they handle N/A power without a problem, but once you get a slight hint of detonation under boost they'll bend in a heartbeat. A turbo H22/23 you produce ungodly amounts of torque, but trying to spin that combo for higher RPMs while under boost your cylinder pressures and piston speeds would be very high so you would have to limit RPMs an just rely on the mid/high RPM power from the turbocharger. I would ramble on all day but I have to get back to work

 

ditto h22si. The h22head h23 block is highly unreliable for a daily driver. A buddy of mine tried this head swap, after 6 months of troubles, he finally decided to say F it and just get a brand new h23a. a pro shop, forgot the name, had a prelude and did this hybrid, they went through 3 motors before they had it running properly. and keep in mind, this was a strict drag car. the h22a or h23a are both great motors to boost. whoever told you it was such a high compression engine was probably talking about the jdm h22a engine, which has 11:1 compression i believe.

 

Hey man, could you do me a big favor and find out who it was that attempted the H22/23 hybrid, or a number where I could get in contact with them? I'm just wondering what modifications they did.

 

Well, i'm not sure which engine you have, but if it's the h22, consider overboring it and get more than 2.3l of displacement(89-90mm). It should be cheaper, and much less of a headache; not to mention the peace of mind having a solid motor verses a timebomb waiting to happen.

The difference in c/r between the h22 and h23 is negligible. If you plan on anything more than 7-8lbs you should upgrade internals anyway. Not that the stockers won't hold out for a while, but if and when they go, it will be a lot more expensive replacing the block than just building it before.

.02

 

my friend kyle did the hybrid, trust me on this.... do NOT waste your time on this! you could easily throw a 50shot of NOS on a h23a and wax a hybrid and still have dependability, all for 500 bucks. But i think nos sucks, so get a h22a You can ask my buddy kyle what they had to do to run this hybrid, typer845@aol.com tell him you are one of anthony's friends.

 

Thanks bro! I'm not even considering doing it, if anything i'm just going to punch out the cylinders for more displacement. I'm mainly wondering just for the hell of it. Knowledge is power!

 

just in case you didnt know, you cannot bore or hone out prelude cylinder walls. they are made of fiber reinforced material. so if you want to do this and upgrade pistons, you have to resleeve your block. get darton to do it, they rock ***!

 

Ya, a year or two back I called a local shop asking how much they would charge to make the sleeves, install, then align bore. Total price was $400 then. I used a set from Darton when I put together a 2.2 VW motor, the cylinder head temps actually went down!

 

You CAN bore and hone the Prelude cylinders. You just can't bore them out very much. There are .25 overbore OEM pistons available the Prelude for rebuilds and there are proper honing instructions in the Helms manual.

 

WHAT, not reliable? NOT worth it ?

First stock bore size are the same, and you can't bore out the stock sleeves
What makes the difference is the stroke, some say the position of the wrist pin. So it can draw more air....but if you are going N/A set-up H23 stock pistons will lose compression All depends on your set up.
.Now having it bored out with some aftermarket sleeves with a 2.3 block is the
Frankenstein......N/A or FI.....Now one thing that plays a major role is DETONATION, I request as soon the break-in period is over DYNO it. A.S.A.P


[Modified by D.specs, 3:04 PM 5/1/2002]

 

Let's get this falacy over with. There are countless overbored h22a's that have been rebuilt with .25 OEM (Yes that means a Honda made replacement part) overbore pistons. They are working fine with high mileage. Did you think that Honda made overbore pistons that can't be used?

Ya, that's called displacement. The longer stroke does not increase the VE of the motor.

 

So since you know so much... Do you bore it out or honed it out. I know that Honda Type S piston comes .25. The hard part is to find so one that does the work

Plus what does VE means......


[Modified by D.specs, 11:50 AM 5/2/2002]

 

It may not increase the volumetric efficency of the motor but it does modify it. With a longer stroke V.E. at lower RPMs is increased slightly, while in the upper RPM range V.E. "should" drop off. It does depend greatly though on how well the head is matched with the airflow capabilities of the bottom-end.
The amount of horsepower an engine makes is directly related to the mass airflow of the engine. Mass airflow is determined by volumetric efficiency VE, and the density (pressure-and-temperature) of the air. In turn, if you know the actual efficency of the engine, and energy content of the fuel used, you can predict horsepower.


[Modified by H22Si, 3:11 PM 5/2/2002]


[Modified by H22Si, 3:16 PM 5/2/2002]

 

Boring and honing are two different things. Boring is the cutting of the cylinder to accept larger pistons and honing is the texturing of the cylinder walls to ensure proper ring seating. Are you saying your having a hard time finding someone who will bore and hone your cylinders? Any automotive machine shop should do the work. Boring an honing the FRM sleeves is no different than on other motors and the proper procedure is outlined in the Helms manual.

With efficency and energy content you can calculate indicated power. Which I never found all that useful. I agree that the VE to rpm map will change slightly, but there other factors regarding the design change of this engine that effect output more than VE being slightly changed relative to RPM.


[Modified by DirtyLude, 9:19 PM 5/2/2002]

 

Forget about mating the h23 block with h22 head. Just go with the J-spec H23 VTEC from the '94^ Accord SiR-T.