I know that the P13, P28, and P72 ECUs are capable with the H22. Which ECU is the best ECU for each application?:
1. N/A
2. Turbo

 

i have a xs engineering chipped P72 for sale.. it was used on a h22 motor and made good power..

look at this review...
http://www.importreview.com/re....html

 

How much you selling the ECU for?

 

From that link, it looks like the P72 is better than the P13 for turbo applications. I'm assuming that the turbo will take care of the low-end power loss. I haven't seen a dyno chart for a P28 ECU powered H22 though.

 

NA: The P72 is the best application, because you keep secondary runner control and will make more low end power. A chipped/converted P75 is also a good choice.

Turbo: The P28 is the best, because you don't need secondaries anyways once you're turbo and pushing air. The P30 is just a P28 with a knock sensor, but you don't need a knock sensor and it's disabled past 5500 rpm anyways.

Our shop sells all of the above, and they come with neato blue powdercoated frames too
Brian

 

In the link a few posts up, the dyno shows that the P72 has less low-end power. I think you meant to say that the P72 gives you more high end power.

 

How much are the P28 and P72? USDM and JDM.

 

No, I meant what I said This is from Hondata's site: "The IAB or secondary intake runner is a set of butterflies in the intake manifold of B18C and H22A engines. The P72 ECU controls the IAB, but other ECUs do not. If IAB control is lost by swapping ECUs then the engine will always run on the shorter intake runners, typically losing 8 hp from 3,000 to 5,500 rpm."

If you're talking about running a stock P72 ECU on your prelude, then you would get results as shown in that dyno. However, only an idiot would run an ECU on his/her car that has timing and fuel maps for another car (aka running a stock unchipped P72 ECU in a prelude)...

The advice I gave was for running an ecu other than the P13 prelude ECU in a prelude, assuming the chip in the ECU is fuel and timing mapped for the prelude motor. If you were to run a prelude mapped chip in a P28 on your car, and then run a prelude mapped chip in a P72 on your car, you would notice more low end because of the IAB control on the P72. This control is not needed on a turbo car.

http://www.solid-technology.com/ecuchipping.htm

Brian

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Firedrake &raquo;</TD></TR><TR><TD CLASS="quote">No, I meant what I said This is from Hondata's site: "The IAB or secondary intake runner is a set of butterflies in the intake manifold of B18C and H22A engines. The P72 ECU controls the IAB, but other ECUs do not. If IAB control is lost by swapping ECUs then the engine will always run on the shorter intake runners, typically losing 8 hp from 3,000 to 5,500 rpm."

If you're talking about running a stock P72 ECU on your prelude, then you would get results as shown in that dyno. However, only an idiot would run an ECU on his/her car that has timing and fuel maps for another car (aka running a stock unchipped P72 ECU in a prelude)...

The advice I gave was for running an ecu other than the P13 prelude ECU in a prelude, assuming the chip in the ECU is fuel and timing mapped for the prelude motor. If you were to run a prelude mapped chip in a P28 on your car, and then run a prelude mapped chip in a P72 on your car, you would notice more low end because of the IAB control on the P72. This control is not needed on a turbo car.

http://www.solid-technology.com/ecuchipping.htm

Brian</TD></TR></TABLE>

So from what you are saying, it seems that the P28 with an H22 chip would be the best ECU for a turbo Prelude, correct? Do you have any dyno charts of different ECUs on H22s?

 

Correct me if I'm wrong but the shorter intake runners are for low-end power and the longer intake runners are for high-end power?
What if you ran both runners at the same time?
If a H22 chipped P72 fixed the low power loss, then why wouldn't it be best for turbo applications?
Running which runner is for turbo applications?

 

Ok, here is the way the runners work: Our intake manifold on the H series motors, like the intake manifold on the B18C1 motors, has 2 sets of runners inside the manifold. When the car is at idle, the vacuum pulls a diaphram that closes off the shorter runners so that the longer runners are used. At a certain point, this diaphram opens up so the car is now using the shorter runners, which are better for high velocity air (hence the reason why most manifold designs you see have shorter rather than longer runners)......
An H22 chipped P72 is the best application period. If you want to spend the extra money, get the P72. However, on a boosted car you're usually pressurizing the intake much sooner than when the secondaries would normally open, so you're not gaining anything. For instance, on my car I'm running a hondata s200 on a P72. My turbo begins spooling at 3K rpms, and the secondaries don't normally open until 5200ish. I want to be on the shorter runners as soon as I start making boost, so I set the IAB activation point to 3200 or so. Essentially, this is the same as just running a P28 and not worrying about the IAB's at all
Hopefully I didn't get anything confused above
Brian

 

I don't have both of my runners hooked up. I don't know which runner is which but the ones you can see right around the top of intake manifold are disconnected. Am I losing performance?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Firedrake &raquo;</TD></TR><TR><TD CLASS="quote">Ok, here is the way the runners work: Our intake manifold on the H series motors, like the intake manifold on the B18C1 motors, has 2 sets of runners inside the manifold. When the car is at idle, the vacuum pulls a diaphram that closes off the shorter runners so that the longer runners are used. At a certain point, this diaphram opens up so the car is now using the shorter runners, which are better for high velocity air (hence the reason why most manifold designs you see have shorter rather than longer runners)......
An H22 chipped P72 is the best application period. If you want to spend the extra money, get the P72. However, on a boosted car you're usually pressurizing the intake much sooner than when the secondaries would normally open, so you're not gaining anything. For instance, on my car I'm running a hondata s200 on a P72. My turbo begins spooling at 3K rpms, and the secondaries don't normally open until 5200ish. I want to be on the shorter runners as soon as I start making boost, so I set the IAB activation point to 3200 or so. Essentially, this is the same as just running a P28 and not worrying about the IAB's at all
Hopefully I didn't get anything confused above
Brian</TD></TR></TABLE>

Is the a H22A chipped P28?

 

Good explanation. A question I have on those secondary runners, is their main purpose is to allow more air into the motor when they open? What would if any advantage be to having them open all the time? Disadvantages to idle or low rpm performance? This would be on a P13 that has been chipped by Dinan a few years back. I can tell you that the chipping helped smooth out the VTEC engagement, as well as raised the rev limiter to 8100. I am in the process of having my H22A1 built, and should have it back in a week or so. I plan on staying NA. If it matters, here is what I am having done: Bore and hone .25 OS, Type-S pistons, 11:1, .25 OS, Eagle H-beam rods, Crower Stage 2 with stock idle cams, dual springs, titanium retainers, 3 angle valve job with minor port and polish, ground crank with all new Clevite bearings, fully tanked with new seals/o-rings everywhere, and manual tensioner conversion.


Modified by 94vtecmn at 4:58 PM 6/10/2003

 

"A question I have on those secondary runners, is their main purpose is to allow more air into the motor when they open? "

I guess you can think of it like that. The IAB is an approximation of a variable length intake, just as vtec is an approximation of variable profile cams. You can read about this in various places. Several cars have variable length intake paths. The idea is to tune the resonant frequency of a section of pipe with the intake cycle to improve volumetric efficiency. Longer pipes have a lower resonant frequency. So ideally you would have long intake runners at low RPM, and they would get shorter as the RPM increases. The IAB does this in two stages instead of with a continuous change. So yes, they are to let more air in...

 

Thanks, that answers my basic question. What about performance improvement? Is there anything to be gained by removing the secondary butterflies? Will I hurt low end, with some improvement through the mid range?

 

The secondary butterflies are just as usefull on a turbo engine, when not boosting, as on a NA engine. When cruising around town or on the highway and anything less than WOT, the engine still benefits from the higher velocity the long runners give the intake charge.

The best would be if you have a standalone, my secondaries open up at 4500rpm, or when intake pressure goes over atmospheric. Otherwise you can simulate this by bypassing the vacuum box that the intake vacuum solenoid uses to store vacuum. That way anytime there is not enough vacuum in the intake, the secondaries will open up no matter what RPM you're at.

 

I don't have both runners hooked up. The runners that you can see on the top of the intake manifold are not hooked up. I don't know which ones those are. Am I at a disadvantage by having it unhooked?

 

bump

 

if the secondary butterflies are not hooked up, that that I'm on a NA setup (jdm bottom with a ported USDM head), would I end up loosing power overall? I noticed my car goes as fast as my friend's H23 untill my vtec kicks in, is that normal ?

 

Okay having a H22 chipped P72 and adjusting the secondary butterfly is like having an shipped P28. For a turbo application, would a chipped P28 have the same top end gain as the P72?

 

Not having IAB's hooked up on the H22A on an NA car will lose a little bit of bottom end. However you CAN still control your IAB with the throttle.

If you run a chipped P28 on an NA or boosted, with or without Hondata, you will still have the low end nicely, unless you are at WOT which you'll be at the top end anyways.

This is mainly something I discovered while swapping the H22A into my 92 VX, running with them open all the time, and then hooking them up to the vacuum as I was stating before.

It may be something you want to think about while using a P28 or not having the secondary butterflies hooked up properly in the first place.

I apologize for the quality, but here is some ideas for you:



Basically, the IAB's will remain closed at little or mid throttle, and in VTEC or WOT, they will open up.

Just something for you to test out.

 

real quick question. why do you have a screw in your vacuum line?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDMlude92 &raquo;</TD></TR><TR><TD CLASS="quote">real quick question. why do you have a screw in your vacuum line?</TD></TR></TABLE>

Quick way of capping off extra some of the nipples.

It was supposed to go to EGR, but EGR is not hooked up.

I'll fix it with a cleaner nipple cover, till then, she works.

 

Ok, I'm confused on the terms IAB, short runner, long runner, and secondary butterflies. I'm getting mixed up. Can someone please clarify this for me?