Megan Racing 4-2-1 Stainless F22 F23 Header , Modification / Install

[A20A1]

Well here is the reality.

The port size is something I had expected to be larger due to the displacement being higher. It is much larger then expected though, the port is 1 X's as tall as ours but about 1.5 X's wider. Here is the comparison of the exhaust port size, it is nearly exact. A20 port 4/5ths the size of F22 ... I think I did the math right. The larger diameter tube will slow down velocity... if you make a good transition there souldn't be too much problems... you might want to make a new pipe in 1.625" (a little larger then stock) diameter from the A20 flange and then up the diameter to the F22 diameter.

• F22 Exhaust Port 100%
• A20 Exhaust Port 80%

The port spacing is pretty good in my opinion. especially for the two center ports. The outer ports will require a little more work on the pipe to get it to bend in enough to meet the A20 ports.

If using an A20 flange, the header tubes can be cut a few inches from the flange and removed or rotated 90 degrees and welded back on, there is no way around modiflying the ports shape because of issues with not enough material around the ports on the A20 flange. Other things you'll need is an A20 flange preferable in the same material as the header tubes. Once you cut the F22 flange, uless you plan to use some of it as a transistion to the A20 flange it's pretty much scrap. Overall this is very doable if you have a welder, hammer, and a torch.

Next step for me is to get a F22 header to work out fitment issues... and no I'd take my custom header over the F22 one anyday... this is for you guys if you want to take this route.

Accord 1997 F22 2.2 liter EX Accord --- Fel-Pro Header Gasket : MS 95535 --- $34.00
The actual number stamped on the gasket is : 94184
* Thank god it was a complete 1 piece gasket and not the 3 piece gasket set that the A20 comes with.
It says on the back that these are the same:

• F22B1
• F22B2
• F22B6
• Engine : 2.2l , 2156cc
• 1994 - 1997 Accord
• -
• F23A1
• F23A4
• F23A5
• Engine : 2.3l , 2254cc
• 1998 - 2002 Accord

This next image makes me very hopeful since it would allow me to use all of the F22 flange...




This is about as good as I can get it...
A20 Ports with F22 Ports turned 90* & circled in white, plus extra flange material added around the F22 port.
I have the scale image on my computer... it's very very close, but you may want to lay it over an actual A20 flange or head or gasket to double check the bolt hole allignment.
300 Pixles/Inch 12 x 3.76 Inches
Here is the shrunken image.



I think prior to cutting off the flange... use the flange as support to keep the oval shape of the F22 header tubes. Cut the flange inbetween the ports, first for the outer most ports... use a torch... hose clamps... a metal bar and start working the angle of the outer two tubes to get them alligned with cylinder port #1 & #4... then remove the flange and then finally cut the header tube to scrap or use later.
Next do the inner most ports. Remove flange material between them... allign them with #2 & #3 then cut the flange off, cut the pipe segments to scrap or use later

I you choose to rotate the pieces of tubes, it will first be fit to the flange and welded as starter tubes... any minor adjustments can be made to the primaries before finally rewelding all 4 tubes to the starter tubes on the flange.
Keep in mind the lower portion of the header... in order to allign with our exhaust you need the 15* tilt. ( 15* DOWN , in our case. ) You may be able to add the majority of the downward angle of the secondary tubes by unbending the tubes where they make the near 90* bend under the oil pan. So instead of having a secondary downpipe that bends 90* degrees... you bend it 75* degrees.

For those worried about port matching, The triangle cut could be used for regular header modification... since the port heights are the same we could triangle cut the header tubes and shrink them horizontally to form circles (_) instead of (__) ovals. It will give a nice transition from the A20 port diameter to the F22 header tube diameter... then with a little bending of the #1 and #4 tubes inwards all the ports should be alligned.
From (__)___(__)_(__)___(__) to (_)__(_)(_)__(_)


At least the oil pickup is on the same side... I have a feeling though that there will still be clearance issues.

[theDougler]

good thinking a20a1 and hopefully it will work

[gfrg88]

what about turbo manifolds??? do you think we would be able to do something similar???

[b20a86lude]

sorry to ruin the thread i want to say awsome work keep up the good work and thank god 4 people like u that make stuff happen

[A20A1]

So thats the difference... the 1994-1997 SE DX LX are 4-1 cast manifold stock, and the EX has the 4-2-1 cast manifold stock.

[AccordEpicenter]

with all that work why dont you guys just build or have an a20 turbo mani made? Think about the cost of buying and then ghetto rig modifying an f22 to work... There is alot of good info in this thread though.

[bobafett]

yeah this is WAY too much work and way too ghetto. just build what you WANT. a20 exhaust manifold flanges are available.

[b8er]

atleast somebody is trying new stuff, i love seeing this stuff, alot of work went into this thread and i say thanks

[bobafett]

true, but at this point you are completely reworking an f22 flange just to get it to fit onto an a20 head. you can BUY a20 flanges. so this makes this whole mod pointless unless you want to save $30 and hack and build your own not perfectly fitting flange.

now if you didnt have to modify it so substantially, i could see this being really benefitial, but since you could never utilize a manifold from this setup without extensive work, i just dont see the point, when with as much fabrication is involved to get an f22 manifold to work, you could have had a a20 manifold built that will fit or function however you want.

but that being said, this is very interesting and maybe someone will put this info to good use and do something cool with it!

[FyreDaug]

So is this the project you want that manifold and downpipe from me for?

btw, you should check your pm's

[A20A1]

Well this was originally just to fit a f22 header, then someone brought up modifying a turbo manifold... I think you can do it even easier then I proposed, you still need an A20 flange though.

As for the header, I think I figured out how to keep the F22 flange and even some bolt holes.

So is this the project you want that manifold and downpipe from me for?

btw, you should check your pm's

Nope, this is to fit a F22 header... greddy, etc. to the A20. It's not for turbo... thats why I wanted the downpipe... I need a placemarket to allign the F22 secondary pipe to the stock exhaust, since I don't have stock exhaust on my car. It's just my custom header + muffler on the end.

Basicly the stock header would go in... I'd make a stationary flange to connect the stock pipe to... then I'll remove the stock manifold and downpipe and then install the F23 header to see if it reaches and aligns with the stationary flange.

[AccordEpicenter]

theres not that much more support for F22s then there are A20s and any REAL race parts tend to be custom fab for these motors anyway

[b8er]

well for some reason im thinking if you got an f22 header, cut the flange, 'squished' the 2 inner pieces closer together and welded them back onto an a20 flange would make alot more sence and be easier then cutting a trianle, bending,bashing, etc. i would also asume that the 2 inner pipes would have alot more stress on them then they were designed for so would you then have a problem of welds cracking?

[gfrg88]

well for some reason im thinking if you got an f22 header, cut the flange, 'squished' the 2 inner pieces closer together and welded them back onto an a20 flange would make alot more sence and be easier then cutting a trianle, bending,bashing, etc. i would also asume that the 2 inner pipes would have alot more stress on them then they were designed for so would you then have a problem of welds cracking?

thats exactly what i had thought, i was going to ask that same question.

[A20A1]

If you are using an A20 flange then you can reshape the horizontal oval to be a vertical oval. Like I said. Then you just need to heat the secondary pipes and bend those.

Part of the how to is to make full use of the header so you don't need to spend time money getting flanges made.
Cutting triangles was first mentioned as a way to keep the Turbo flange intact on the F22 manifold while using an A20 flange.
For the F22 header flange on the A20, there is no way to reshape the F22 flange ports and size them right horizontally so you need to cut cut cut. You don't triangle cut the header flange, you just cut it up and reweld it so you have a) bolt holes and b) port shapes simmilar to the A20. Triagnle cutting the header tube was a way to taper the tubes to meet the smaller port diameter.
If you don't taper or cut the expanded F22 original oval off altogether, and instead you just squish the oval the other way, you'll have what I outlined in the black and white image above. The ports being very close to the A20 diameter on the flange but the header tubes leaving a rather large lip aroung the ports on the flange. This lip is so big and such a quick transistion from port to header diameter that it will act as a major "STEP" like that in Stepped headers. The Major part is what concerns me though, if the lip was smaller I would leave it as is and consider it a bonus.

Really if you don't have easy access to an A20 flange the best thing to do is cut the flange up and make it's ports closer to the A20's while using some of the bolt holes already there, then cut off the ovals on the F22 header pipes altogether, those pipes were probably expanded instead of pressed to get that big of and oval shape from that size header tube so the metal in that area is thinned.
Removing the thinned metal decreases the tune diameter and reduces the lip. Also depending on how much is removed from the header tube may bring the flange closer to the bends. If the flange is close enough to the bend the header will tilt itself towards the front cross member. So while that helps the secondary angle it hurts both header tube length and if it hits the Front :thumbsdown.

i would also asume that the 2 inner pipes would have alot more stress on them then they were designed for so would you then have a problem of welds cracking?

Nothing is going to be under stress when I'm done with it, all the header tubes will allign with the ports prior to welding anything to either a modified F22 or A20 flange, it's not like I'm bunching the pipes up and then using the welds to hold them in place... the pipes will hold their place/shape on their own.

well for some reason im thinking if you got an f22 header, cut the flange, 'squished' the 2 inner pieces closer together and welded them back onto an a20 flange would make alot more sence and be easier then cutting a trianle, bending,bashing, etc.

You are missing a critical part; you'd still have horizontal ovals with no transition to the A20 ports. Also you are doing it wrong. The Inner pieces do not need to move... the outer tube are the problem ones, they are not even close to the A20, they are the ones that need to be squished closer together.

[AccordEpicenter]

you can still get a20 exhaust flanges made and for cheap too (Under $50 or so) I paid like $30 for mine... I sure as hell wouldnt be using a hacked up F22 flange, but changing flanges and moving/bending runners could be viable if you got the original part for cheap. While this would work for a header, i dont think it would work very well for a turbo manifold due to the thicker construction

[A20A1]

Yeah I agree, and I didn't even want to do a tubro manifold, this was originally just to do a header.

I'm trying to cut costs where I can... if it turns out the header flange leaks or is otherwise unusable, everthing will stil be set to weld on an A20 flange. So the process I will eventually use and write out for you guys will be the same for anyone using the F22 or A20 flange.

[b8er]

You are missing a critical part; you'd still have horizontal ovals with no transition to the A20 ports. Also you are doing it wrong. The Inner pieces do not need to move... the outer tube are the problem ones, they are not even close to the A20, they are the ones that need to be squished closer together.

yea i was thinking about that on the way home from work today, anyways i hope to see everything work out and work out good

[A20A1]

As long as no one out bids me I should have a header to play with soon.

[AccordEpicenter]

well yea you can get cheap chinese ebay headers for f22 easily... To reshape the runners near the flange you could use a vise and good judgement and squish them to your desired shape.

[A20A1]

Is that why the site, site feedback, and responses had poor grammar and misspelling... I was looking at those but they looked too low of a price to be real. I was in the market for used namebrand headers and thats what I'm getting.

[AccordEpicenter]

they are real, but the quality usually just sucks, poor welds, thin/cheap materials, paper thin flanges usually, with suspect fitment... I cant vouch for all of the different guys on ebay selling cheap cheap headers etc but if i were you id do some research about the product and seller before you start buying junk. Usually for car stuff you get what you pay for, thats why say, a DC sports header a much higher price than say, a pacesetter. You get what you pay for.

[A20A1]

This isn't the one I got, but it was my backup incase I didn't get the other header.

If anyone wants to try modding one on their own, this is pretty much as cheap as they come.
http://cgi.ebay.com/ebaymotors/ws/eB...RK%3AMEWA%3AIT

[A20A1]

[MessyHonda]

so did it work?