I know this has been done before on F22B motors and even on some F23 motors, but everyone always seems to just slap it on there with no port matching, or with absolutely no control of the IABs. To me that kinda nullifies the whole point of swapping it, so I'm gonna take a stab at it, doing it the 'correct' way.

My goal is to install the H23 IM with an aluminum adapter plate to blend the larger H23 ports down to the F23 ports with as little turbulence as possible, control the IABs using my ECU, dyno tune to find the optimum engagement point for them, and provide before and after dynos to demonstrate the true gains (or losses) of this modification.

Parts thus far include:

-H23 Intake Manifold
-JDM H22 Fuel Rail
-Bisimoto H23 Heat shielding gasket
-1/2" 7000 series Aluminum plate
-74mm Custom TB
-Longer IM studs

Work to be done:

Chris @ Polar Bear tuning will be fabricating the 74mm custom TB, polishing the H23 IM, and port matching it to the TB.

Tuning will be performed by Joseph Davis on a Dynacom dyno at Blue Ridge Motorsports in Morganton NC.

All other fabrication, installation, and R&D will be done by myself, along with some input from you guys.

I'll have some photos up tomorrow, and post up my progress so far. My intended completion date for this is around the 15th of Nov, with dyno tuning taking place around the first of Dec.

 

post pics when you're done, i wanna see'em.

 

I looked at this a while back and decided it was too much work to be worth while. I figured it would require serious head work to match the ports, and was concerned about getting into the water jacket if I opened it up that much. I guess a with transition plate you solve some of that problem. What do you plan to do about the coolant port. I don't know if it was due to core shift or what, but the H23 mani I had missed the f23 head coolant port by quite a bit.

Anyway, good luck

 

The coolant ports actually overlap by ~40%. Some people have done the swap using the F23 IM gasket, and had no problems, but as I stated I want to do this the correct way. I already have the mounting holes drilled into the adapter plate, so I simply have to trace the H23 gasket on one side and trace the F23 gasket on the other side, then drill diagonally to match them up. The die grinder will take care of the finishing touches.

Once this plate's done, it will probably be my masterpiece of fabrication on the car. lol

 

If I'm not mistaken, you have to look into the coolant pipe. possibly from an F22Ax
And also the thermo housing for the H23 as well.

And if you happen to sell that F23 Intake Manifold let me know. Looking for this IM for a while

 

Yeah, I've heard about some of those issues as well. I have a friend who's already done the swap, but with no adapter plate and no IABs, who is giving me tips as I go along.

Already sold all my F23 IM's except the one that's on the car now. I'm pretty sure someone posted one for sale in the Wanted/For Sale thread recently.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AFAccord &raquo;</TD></TR><TR><TD CLASS="quote">Yeah, I've heard about some of those issues as well. I have a friend who's already done the swap, but with no adapter plate and no IABs, who is giving me tips as I go along.</TD></TR></TABLE>

I myself tried this swap, but stopped cuz I forgot about the coolant pipe (which I have now) and Thermo housing.

Reason I haven't performed the swap: Since I have everything for a complete head swap (F22A6), I might as well go that route. I would gain more from the slightly more aggressive A6 cam and I wouldn't have to worry about the coolant leak between the head and IM

 

Here are a few pics comparing the gaskets.





Here you can see that if the F23 gasket were used, it would effectively seal the offset between the H23 IM and F23 head.

 

Moar Updates!

Got all the holes drilled out. Some are prettier than others, but it fits squarely against the head. Good enough for Government work!












Now I need to source some longer studs. I'll be dropping the plate off at the machine shop next week to be trimmed and have the rough shape of the F23 ports drilled out.

 

Nice job, can't wait to see this thing done. Where are you going to be looking for the extended studs?

 

update?

 

I plan on finding the studs from a giant Ace hardware here in town. If I can't find them there, I'll just have to order them online. I ordered some various pieces from Honda yesterday, like the spaces to mount the fuel rail, and rubber rings for the water pipe.

I've been searching for a machine shop that can cut out the initial shape of the ports for me. Unfortunately there's only one place within about an hour's drive that can do it, and since they usually just do commercial work it's going to be towards the end of next week before they can fit me in.

My die grinder wasn't doing too hot shaping the aluminum with any of the bits that I already have, and again, there's not a good selection locally. However I did find a dremel bit that seems to shape the metal nicely.

In the meantime, I've got a Quaife LSD to install, and some E46's to retro-fit. Just wish these were for me.


Modified by AFAccord at 10:09 AM 11/1/2008

 

nice looks like you're busy. Where did you get that plate anyway, how thick is that?

Keep us posted

 

The plate I purchased from Fortal Aluminum, a distributor on eBay for ~$28+ shipping. It's 5"x 25"x.534".

Most distributors I found were selling 1'x2' plates for ~$64 per square foot, but I only need 4"x16" to cover all the ports, passages and bolts.

Once it's mostly finished, I plan to have about 1/16" milled off both sides to make sure it's flat with a good surface for the gaskets to mate to.

 

Cool nice to know

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by AFAccord &raquo;</TD></TR><TR><TD CLASS="quote">The plate I purchased from Fortal Aluminum, a distributor on eBay for ~$28+ shipping. It's 5"x 25"x.534".</TD></TR></TABLE>

another place to check out is Metal Express

for a piece of 5x25x1/2 6061-t6 aluminum it would be $32 (plus shipping if there isn't a location near you).

I've bought some metal from them a couple times and prices have been pretty good, plus they are local so I can usually get stuff within an hour of calling.

 

Their site looks awesome! I know I checked over 25 suppliers online, and 5 locally, but all the prices were ridiculous!

 

if you look at a "plate" of 6061-t6 aluminum of the same sizes I think it said $55 but if you look at the "flat", it's only $32 for the same sizes. The "flat" is extruded but since you plan to mill both sides flat at the end it wouldn't matter.

just have to look at the different options to see what way is going to be cheaper.

 

I've got this set of carbide bits and they are pretty good for aluminum. they do tend to load up, but they should do what you need pretty well.

http://www.eastwoodco.com/jump...ODUCT

Eastwood is about the most expensive place on earth to buy them, but summit or jegs should have the same thing.

the studs you might have to get from Mcmaster carr.

 

Cool! I've actually got that first bit (on the left) in a dremel diamond bit, and the 2nd and 4th ones I have as well, but i'm not sure what they're made from. I've been using that last one the most so far, but I'll probably go to the second one once I start flaring the ports out.

Good find!

 

cool project. this half inch spacer might also move your powerband down a little bit. good stuff. throttle body spacers are common power mods for all types of engines

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by frosti108 &raquo;</TD></TR><TR><TD CLASS="quote">cool project. this half inch spacer might also move your powerband down a little bit.</TD></TR></TABLE>

Hopefully not. The point of the manifold swap is to utilize a better flowing manifold with shorter runners, hence moving the powerband upwards. The idea is to have the plate as thin as possible to keep the runner length short, while being thick enough to funnel the air into the F23 ports without creating a bottleneck or slowing down the air's velocity.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by frosti108 &raquo;</TD></TR><TR><TD CLASS="quote">good stuff. throttle body spacers are common power mods for all types of engines</TD></TR></TABLE>

Thank you for your valuable contributions.

 

Just picked up the H23 water pipe and Thermo housing.

 

why would you want to move the powerband upward?

 

I don't know if the H23 water pipe is going to work. They look a little different from A6 water pipes.
You probably know this as well, but for information sake for people who don't know. Both H23A1 and F22A6 are almost the same. Differences are runner length A6 are shorter by 1/2" maybe, Throttle bodies are different in size (H23 is bigger) and bolt configuration, A6 TB doesn't have the FITV bolted under it (H23 does), and the IACV is different as well. Oh yeah, H23 plenum is bigger.

H23:
http://slhondaparts.com/browse...=true

A6:
http://slhondaparts.com/browse...=true

Maybe you can mock up the water pipe you just got to the IM and take a pic. I wanna see