F22A1 to H23 Intake Manifold Swap Questions

[SOHC-FTW]

Yeah, there is a distinct loss of low end torque, but also a noticeable increase of mid and top end power. And the engine is about twice as loud as it was @ WOT.

F1 F22 intake growl!

[jdm92_accorn]

still sounds better with 4 holes vs 8, lol. and even better with compression

[Mishakol129]

I mean gut the plate and make the runners look like this.



Removing the throttle plates is only taking away some of the turbulence.... If you have it like the above intake there is no restriction and the runners are still the same length....more volume though.

What kind of power increase did you have when you installed that? I am about to install mine once I get the gasket in on monday.

I'm curious to know what im in for on this. There's no cat on my car right now and it definitely feels like it needs more air. Just how much is too much? I figure it can't hurt as long as I keep a stock TB on it which I do. I ported out the TB and the ends of the runners, its a 62mm TB.


btw it looks liek you deleted your FTIV and IACV, i'm not doing that.

[Jarrett]

Yes, it can hurt. Remember that whole property I told you about called velocity?

Truthfully, what other supporting modifications are you installing concurrently in order to see benefits from this type of effort.

[Mishakol129]

Yes, it can hurt. Remember that whole property I told you about called velocity?

Truthfully, what other supporting modifications are you installing concurrently in order to see benefits from this type of effort.

Velocity yeah, but if you look at it this way the TB creates velocity and so do the runners.


The mods I have are I/E/H, P12 ecu, no cat and cat back exhaust. Its not much but it definitely something. The intake on the f22a1 is just restrictive, I wanna put this bad boy on there to free it up. I can feel the restriction at high rpms and at the mid range.

[GhostAccord]

With no cam or internals I think you may see some velocity issues. Maybe a little bit of a stumble off the line and/or lack of throttle response. it will help top end.... However that may also be where the stock cam and ECU will start to inhibit you.

That being said, I think you will really see it show it's true colours if you were to do a few more things. Up the compression to 10.5-11:1, raise the power band up a little with an aftermarket cam, also a new set of A6 valve springs, larger injectors and last but not least, a good tune.

[Mishakol129]

With no cam or internals I think you may see some velocity issues. Maybe a little bit of a stumble off the line and/or lack of throttle response. it will help top end.... However that may also be where the stock cam and ECU will start to inhibit you.

That being said, I think you will really see it show it's true colours if you were to do a few more things. Up the compression to 10.5-11:1, raise the power band up a little with an aftermarket cam, also a new set of A6 valve springs, larger injectors and last but not least, a good tune.

I'm sure it will help with gas mileage if not anything else lol. Like one guy said trial and error.

But to up the compression and install new valve springs I would have to remove the head right? How do you raise compression? Sounds like time and money that I am lacking.

So even the P12 ecu will have problems? Ecu tuning is not my thing, i have no idea how to do that. I'm not interested in forking out top $$$ to have it done either.

I'll maybe throw a stage 1 cam in there and let it be for now.

[GhostAccord]

I'm sure it will help with gas mileage if not anything else lol. Like one guy said trial and error.

But to up the compression and install new valve springs I would have to remove the head right? How do you raise compression? Sounds like time and money that I am lacking.

So even the P12 ecu will have problems? Ecu tuning is not my thing, i have no idea how to do that. I'm not interested in forking out top $$$ to have it done either.

I'll maybe throw a stage 1 cam in there and let it be for now.

Yes, the P12 may help you out a little bit here! It is still set to F22 limits.

How does allowing more air to flow into the combustion chamber equate to better MPGs?

I don't know if I have the energy to get into the basics of engine design and engine management or basic engine theory.

To raise compression you have to remove the block.....not just the head! To do it properly you have to replace the pistons. The valve train and cam can be done with the engine in the car and the head on the block....

I realize that you are on a tight budget.... Unfortunately adding power doesn't normally work well in that budget range.

You should buy some engine building and engine management books or see if your local library carries any. Then you can sit down for a while and read.... Not sure why you keep assuming things about engine dynamics when the facts are available.

[Jarrett]

Yes, you have to remove the head to increase compression. Yes, you have to have your car tuned to make most of these modifications work. Yes, these things cost money as do most things involving car modification. What do you have against saving money until you can afford to buy the things necessary to do this the right way? How many more posts do you plan on making where you ask if you can do a short cut instead?

[cloudasc]

Wow... oh.... wow....

1.) IAB's left always open, or hooked up to vacuum will cause low end power loss.
2.) OP, that extensive amount of work to your intake is not going to be very beneficial, as stock head can only intake so much air (without boost), and unless your porting the head, changing to a more aggressive cam, increasing compression, etc, the work you performed to your manifold will likely hurt performance.

I have an a6 runner / h23 plenum & tb setup, that I also sent to CHR Racing to have it gasket matched/porting, polishing, flowbalancing. In the process of the work, it was put on a flow bench and various CFM's were recorded.

The runners:

With the butterflies installed, 60mm throttlebody:

Overall numbers (top numbers are with butterflies open, bottom closed):


And here is the head flow information:


Oh and the a6's runners are even shorter than the h23's, adding a gutted spacer to an a6 (aka double-stack), makes it about the equivalent length of the h23. Shorter runners are better for top end, longer are better for low end (Reference IAB's).

[GhostAccord]

O/T..... Did you ever have the opportunity to flow test the intake head combo?

[cloudasc]

O/T..... Did you ever have the opportunity to flow test the intake head combo?

No I have not, as my head only had the valvesprings upgraded. In the future it will be modified. So the gasket matching on the runners technically is for nothing at the moment as the head hasn't been gasket matched yet. The head flow numbers also should come from the same source as my intake manifold CHR Racing. The numbers speak for themselves though.

[GhostAccord]

and the numbers look good.

[cloudasc]

^^ Not as good as your ITB's

[Mishakol129]

Is this with a chipped or an unchipped ecu? I was running this setup before but it was with a P12 and the power below 4,000 suffered because of it. Even with the A1 manifold the power down low was great, it pulled my wagon very well. Now its not so great down low... I am now planning on installing the A6 ecu with the butterflies hooked up, not going to take out the gutted plate just going to add the plate with the b-flies on top, which Should give me 5 more hp and tq. Just got to find 2 CB7 AC bolts and 3 Civic/Lude AC bolts.

I would tune my car with the gutted spacer, but I simply don't have to money to do so. Plus, the idea of hooking up the IAB's fascinates me, and I just picked up an Pt6 ecu at the JY last Saturday, and I have the A6 cam installed.