F22A1 to H23 Intake Manifold Swap Questions

[Jarrett]

YOU should not mess with the runners so you don't chance messing things up. And it would be a porting procedure that removed the casting flash. Polishing is done afterward. Otherwise you'd just be making that a shiny burr.

You need a PT6 and a black box. Before you start, don't do the routine where you try to ask your way out of it via some alternative method. It's how to properly run them and that's what you need. Once you've got them and they are operational simply turning on the engine will apply the vacuum needed to close the butterflies. Then, at 3900rpm the solenoid will actuate the diaphragm to open them up.

[Mishakol129]

YOU should not mess with the runners so you don't chance messing things up. And it would be a porting procedure that removed the casting flash. Polishing is done afterward. Otherwise you'd just be making that a shiny burr.

Would that really be worthwhile and could I do it myself?

Here's a guy that did it with a dremel tool,

You need a PT6 and a black box. Before you start, don't do the routine where you try to ask your way out of it via some alternative method. It's how to properly run them and that's what you need. Once you've got them and they are operational simply turning on the engine will apply the vacuum needed to close the butterflies. Then, at 3900rpm the solenoid will actuate the diaphragm to open them up.

Like I said in my other posts I'm not going to get the black box. Its not cause i'm lazy its just I don't wanna spend another $50 on an ECU when I have the P12 ECU. Just the way its gonna be. Many other people have done it that way, and some (Like jdm92_accorn) will tell you its even better that way.

I dyno tested the iabs I made more power without them all together.

I just wanna know how the butterflies open when you just hook the vacuum up with no box. Is it better to leave the vacuum off or on? It seems they would stay closed all the time.

[SOHC-FTW]

Thing's aren't as easy as one of the million DIY port jobs on youtube nothing is.

Before you start hacking away try your hand on that A1 mani. And as i said in this VERY thread sure you can run straight vaccum or you can delete the IAB plate altogether, but to benefit the IAB's which help low end tq and open at 4400 (IIRC) to then help topend you need the black box an pt6.

[Mishakol129]

Thing's aren't as easy as one of the million DIY port jobs on youtube nothing is.

Before you start hacking away try your hand on that A1 mani. And as i said in this VERY thread sure you can run straight vaccum or you can delete the IAB plate altogether, but to benefit the IAB's which help low end tq and open at 4400 (IIRC) to then help topend you need the black box an pt6.

So without the black box they open before 4400 or after
It seems to me by how the thing works that it won't open at all if the vacuum is hooked up, since they are already open and it is vacuum itself which causes them to close. Unless I am misunderstanding the dynamics of the intake during higher rpm's. I heard not hook the vacuum up at all.


About the porting job i've read that you need the runners to be rough at the fuel injector end for better fuel atomization(?). I've also heard that its not even worth porting the IM cause the gain is so little. I'd like to know what your take on it is.

[SOHC-FTW]

If straight vaccum they will open up around 1500-1700 thus killing the lowend. With the IAB's properly setup they are closed until 4400 thus helping lowend and then opening up for the topend, sort of like a 4bbl carburetor.

I wouldn't waste your time unless you're doing a build and need every ounce of power. And then i would just delete the IAB plate altogether.

[Mishakol129]

If straight vaccum they will open up around 1500-1700 thus killing the lowend. With the IAB's properly setup they are closed until 4400 thus helping lowend and then opening up for the topend, sort of like a 4bbl carburetor.

I wouldn't waste your time unless you're doing a build and need every ounce of power. And then i would just delete the IAB plate altogether.

How do they open up at 15 to 1700, explain to me cause i'm having a hard time understanding. It is the vacuum which causes them to close. So what this means is vacuum does not exist in the intake manifold at 15 to 1700 rpms causing the IAB's to open? So its only at idle that vacuum exists?

That's kind of confusing.


You're right its probably not gonna do anything noticable.

[GhostAccord]

Yes...vacuum is highest at idle and it diminishes as the throttle is opened. Now if you have a restrictive throttle body or intake, where your vacuum actually drops off will differ.

[Jarrett]

Consider three thing before relying solely on the fact that someone said they made more power with the setup you mentioned.

1) Was it just peak or top end power? If so, there may have been significant losses in the low end because of all that additional airflow. Velocity is key here.

2) Did he have other supporting modifications that may have required more air flow on the intake side? If so, that could explain the gains to a extent.

3) Let's suppose it does make better power without the black box and PT6 hooked up. This is on a dyno at WOT. You don't drive around like that. You'll be constantly wasting gas because of all the additional air in the bottom end without velocity.

[SOHC-FTW]

Consider three thing before relying solely on the fact that someone said they made more power with the setup you mentioned.

1) Was it just peak or top end power? If so, there may have been significant losses in the low end because of all that additional airflow. Velocity is key here.

2) Did he have other supporting modifications that may have required more air flow on the intake side? If so, that could explain the gains to a extent.

3) Let's suppose it does make better power without the black box and PT6 hooked up. This is on a dyno at WOT. You don't drive around like that. You'll be constantly wasting gas because of all the additional air in the bottom end without velocity.

Yep can't deny it if you want the IAB's to work properly do it right, being his is an A/T it would be best to keep a happy medium which the OE setup provides.
The other ways are for different builds all around, i only mentioned the other ways due to him refusing to setting it up like OE.

[toycar]

Op



The runners function just like Ghost said.


The reason you loose low end torque, is a lack of pressure in the manifold. Lower RPM's are drawing less air than higher rpm's. The manifold is large enough that when the secondaries open early the engine cannot maintain pressure at such a low RPM and therefore the low end suffers. You will feel a difference, in a bad way, not having the box hooked up correctly.

Now if you are going to drag race the car or something, than yeah, removing the secondaries would be OK and you would benefit. How much time are you going to be spending around 6,000 RPM's?


Not much, keep the box. The only purpose of the car is racing, delete them. If this is your daily, keep the box and hook it up correctly.

[Mishakol129]

Consider three thing before relying solely on the fact that someone said they made more power with the setup you mentioned.

1) Was it just peak or top end power? If so, there may have been significant losses in the low end because of all that additional airflow. Velocity is key here.

2) Did he have other supporting modifications that may have required more air flow on the intake side? If so, that could explain the gains to a extent.

3) Let's suppose it does make better power without the black box and PT6 hooked up. This is on a dyno at WOT. You don't drive around like that. You'll be constantly wasting gas because of all the additional air in the bottom end without velocity.

I get what you mean, Honda must have set it up like that for a reason, but about the fuel mileage thing Jdm Accorn said that he actually had an increase in fuel mileage without the IAB's hooked up,

actually i noticed a slight increase in mine. another 1 or 2 in the city and 2 on the highway. not bad for a bump in power.

In post 26

[Mishakol129]

Op



The runners function just like Ghost said.


The reason you loose low end torque, is a lack of pressure in the manifold. Lower RPM's are drawing less air than higher rpm's. The manifold is large enough that when the secondaries open early the engine cannot maintain pressure at such a low RPM and therefore the low end suffers. You will feel a difference, in a bad way, not having the box hooked up correctly.

Now if you are going to drag race the car or something, than yeah, removing the secondaries would be OK and you would benefit. How much time are you going to be spending around 6,000 RPM's?


Not much, keep the box. The only purpose of the car is racing, delete them. If this is your daily, keep the box and hook it up correctly.

There are people though who hooked it up without the IAB's and said there was no difference. JDM accorn doesn't have that many mods and is NA and said he actually had more power without them. I'm interested in hearing more from people like him who actually experienced it with and without the IAB's.

[toycar]

There are people though who hooked it up without the IAB's and said there was no difference. JDM accorn doesn't have that many mods and is NA and said he actually had more power without them. I'm interested in hearing more from people like him who actually experienced it with and without the IAB's.

Its all good.


Believe what you will. The reason that performance suffers was clearly explained, and is very much so related to pressure.


If you put a 4" exhaust on your car, performance would suffer too. Its all about airflow my guy.


You create turbulance when you cannot generate pressure in the manifold which slows down air flow. When flow suffers, performance does as well.

Same reason you want that texture inside the intake manifold-the texture works like a golf ball. The dimples trap air, which then provides a smoother surface for the air to travel against than polished metal. Same concept applies to a golf ball and the dimples they have.


Anyways, its all about airflow. If you cannot generate pressure in the manifold, you will not move as much air. You will not generate pressure until 4-4500 rpm's, which is about when they are designed to open in the first place.


No offense, but I get the impression that some of the dynamics of airflow are a bit over your head or beyond your study. Read up on it, don't just take my word or someone elses.


Its science, not opinion. Go learn.

[SOHC-FTW]

There are people though who hooked it up without the IAB's and said there was no difference. JDM accorn doesn't have that many mods and is NA and said he actually had more power without them. I'm interested in hearing more from people like him who actually experienced it with and without the IAB's.

Not hard to understand your STOCK automatic f22 will perform better with IAB's.

And jdm's car has a cam and every bolt on mod known to mankind and they are the best money can buy he isn't making that power on ebay parts an hopes and dreams.

[jdm92_accorn]

the iabs do work and can make more power with them working depending on health of the engine mainly and camshaft choice secondly. the reason the iabs installed may make more power is runner length and plenum volume NOT because of the valve itself. the longer runners helps with low end power which is where the stock cam thrives. as soon as you change out to an aftermarket cam you'll want them removed.