Year/Model/Trim Differences - Where's My Power

[StoobyMcDooby]

g unot?

[owequitit]

Very true Scott, it is very possible that the ECU alone might not be any of the upgrade, it might have a different intake manifold (albeit slightly) and a different catback system which could increase power...the P12 just might be better set up to utilize it. Of course then I'd argue that the P12 should optimize a I/H/E F22a1.

I definitely plan on doing the H plenum in the future when I do my A6 manifold swap, I'm just curious, I'm sure you can understand that.

I knew the EX had a dual tip muffler, but I didn't realize the B pipe was different as well. That more than likely negates the "big" advantage of the A4 header like you said. Of course that's with original exhaust, I'm sure the second a place like Midas does a system, all Accords become the same.

I think I just need to locate a P12 ecu and pop it in and see what happens.

That would be the best option. I think the EX had slightly larger piping. There are so many ways to get incremental flow improvements it is absurd, so maybe just the muffler made a difference, and yes Midas puts the same thing pretty much on all of them... LOL.

The ECU could be more agressive too though. Does anybody know the recommended octane rating?

[mondojackal]

That would be the best option. I think the EX had slightly larger piping. There are so many ways to get incremental flow improvements it is absurd, so maybe just the muffler made a difference, and yes Midas puts the same thing pretty much on all of them... LOL.

The ECU could be more agressive too though. Does anybody know the recommended octane rating?

just curious here..why would the octane rating be any different? if the CR is still 8.8, then would the motor benefit from the higher octane rating? would the ECU just advance the timing?

[owequitit]

just curious here..why would the octane rating be any different? if the CR is still 8.8, then would the motor benefit from the higher octane rating? would the ECU just advance the timing?

An increase in octane rating would generally be a good indication of either a more aggressive build, or more aggressive tuning.

[mondojackal]

An increase in octane rating would generally be a good indication of either a more aggressive build, or more aggressive tuning.

so you're assuming that since the P12 seems to be the 10hp difference that it must have more aggressive factory tuning and can take advantage of the higher octane?

[gloryaccordy]

so you're assuming that since the P12 seems to be the 10hp difference that it must have more aggressive factory tuning and can take advantage of the higher octane?

More advanced ignition timing methinks

[owequitit]

so you're assuming that since the P12 seems to be the 10hp difference that it must have more aggressive factory tuning and can take advantage of the higher octane?

I am not really assuming anything. I think it is a possibility.

We know the exhaust manifold and cam are the same.

We aren't sure about the IM.

We know the ECU is different.

The intake, the exhaust or the ECU are generally the first places we would expect them to go to find more power, since we know the internals seem to be the same.

Perhaps the exhaust counted for some, and perhaps the IM accounted for some, but maybe the ECU did too.

And yes, since Honda designs most of their cars to take advantage of the crappiest gas in town, there may be more power in the ECU, although MRX wasn't having terribly good results with that, so who knows.

Maybe they put a larger TB on it. Are those parts the same Mike?

[mondojackal]

I am not really assuming anything. I think it is a possibility.

We know the exhaust manifold and cam are the same.

We aren't sure about the IM.

We know the ECU is different.

The intake, the exhaust or the ECU are generally the first places we would expect them to go to find more power, since we know the internals seem to be the same.

Perhaps the exhaust counted for some, and perhaps the IM accounted for some, but maybe the ECU did too.

And yes, since Honda designs most of their cars to take advantage of the crappiest gas in town, there may be more power in the ECU, although MRX wasn't having terribly good results with that, so who knows.

Maybe they put a larger TB on it. Are those parts the same Mike?

i wasnt trying to say that you were assuming anything.
i do remember anoine's ecu and tuning thread where he talked about being able to unlock more midrange power, but nothing on the top end.

so the conclusion so far is that it's either intake mani, exhaust, ECU, or any combination of the preceding. cool.

[AccordWarrior]

Maybe they put a larger TB on it. Are those parts the same Mike?

I haven't actually looked at that yet, I should do that when I get some free time today. I never thought about any differences like that.

Now you got me wondering about compression and timing, along with that ECU thing.

I do know the intake manifolds do NOT share part numbers between the cars, but I don't know what the differences are.

I believe if I recall correctly MRX got 6 hp in the mid-high range, but lost low end, I'll have to dig that up sometime today.


***EDIT***

Scott, I just referenced the throttle body numbers. Interestingly enough, not only does the Prelude S not share the DX/LX intake manifold part number, but the throttle bodies ARE a different part number. So there may be slight differences in those.

For the sake of information, I have found that the A4 and A1 share a common throttle body, where the A6 has a unique piece. So even though the A1/A4 TB will bolt up to the A6 manifold, there may be slight differences in flow.

So it might not just be the P12 where most of the gains are realized. Of course I wouldn't swap the A1 manifold off of a Prelude into an Accord for the sake of doing it...but it means there must be slight changes.

I'd love to know if the A1 TB off the Prelude is bigger than either the A1/A4 or A6 pieces.

There goes my, add 10 hp to my mom's car for the cost of a P12 plan.

[mondojackal]

There goes my, add 10 hp to my mom's car for the cost of a P12 plan.

on the contrary..you don't know that all of those little differences add up to like 2 extra hp and the ECU adds 8 hp...who knows? just try it and see. im sure some NA f22 guys might be interested.

[owequitit]

I haven't actually looked at that yet, I should do that when I get some free time today. I never thought about any differences like that.

Now you got me wondering about compression and timing, along with that ECU thing.

I do know the intake manifolds do NOT share part numbers between the cars, but I don't know what the differences are.

I believe if I recall correctly MRX got 6 hp in the mid-high range, but lost low end, I'll have to dig that up sometime today.


***EDIT***

Scott, I just referenced the throttle body numbers. Interestingly enough, not only does the Prelude S not share the DX/LX intake manifold part number, but the throttle bodies ARE a different part number. So there may be slight differences in those.

For the sake of information, I have found that the A4 and A1 share a common throttle body, where the A6 has a unique piece. So even though the A1/A4 TB will bolt up to the A6 manifold, there may be slight differences in flow.

So it might not just be the P12 where most of the gains are realized. Of course I wouldn't swap the A1 manifold off of a Prelude into an Accord for the sake of doing it...but it means there must be slight changes.

I'd love to know if the A1 TB off the Prelude is bigger than either the A1/A4 or A6 pieces.

There goes my, add 10 hp to my mom's car for the cost of a P12 plan.

Well, maybe not. I can tell you that even though the part #'s may be different, the TB's on the A1/A4 and A6 are identical. They measure exactly the same in all respects. My A6 manifold came with one, but the TPS was broken, so I used my original. Not before I attacked it with the micrometer though. LOL.

Maybe the different part # has to do with it being built in a different factory or something...

It could have also been minor changes for that particular installation...

[owequitit]

Here is a link to the only P12 I could find.

Don't know if you want to spend the money on something that may or may not pan out or not.

http://cgi.ebay.com/ebaymotors/ws/eB...MakeTrack=true

[AccordWarrior]

Here is a link to the only P12 I could find.

Don't know if you want to spend the money on something that may or may not pan out or not.

http://cgi.ebay.com/ebaymotors/ws/eB...MakeTrack=true

Eeek...$75 for a P12? No thank you...for that I'd invest in a port and polish on my A6. All of this was centering around getting a P12 for $25 or so.

Of course now all this talk has driven up the price of that ECU. I'll keep my eyes open, I mean I got my PT6 for under $30 on Ebay.

Thanks for the help Scott. I just appreciate the help b/c you know what I'm going for by looking into all of this information.

[owequitit]

Eeek...$75 for a P12? No thank you...for that I'd invest in a port and polish on my A6. All of this was centering around getting a P12 for $25 or so.

Of course now all this talk has driven up the price of that ECU. I'll keep my eyes open, I mean I got my PT6 for under $30 on Ebay.

Thanks for the help Scott. I just appreciate the help b/c you know what I'm going for by looking into all of this information.

Yes, and I have been wondering a long time myself.

They didn't get it from a compression bump either.

We have two main variables left. The ECU and the IM/TB. If we can solve either of those, we will be golden.

It may end up being a combo of the two.

I wish I had easier access to a dyno, because I wanted to quantify A6 vs A4 manifold, and then H22 TB and plenum vs A6 setup. If the A6 mani and cam are known to be worth 10HP, I probably got pretty close to that with TB and plenum, because the noticable increase was just about the same.

I am logically guesstimating my HP at about 145-150 crank HP or so. I pulled slightly on a new Accord 4cyl auto a week or two ago. It was more inching up on him, but the fact that it happened at all should make my estimate fairly close. Based on power to weight ratio and gearing.

Anyway, I could see them getting 5HP or so out of a larger TB and then maybe another 5 out of an ECU upgrade.

[hoonda83]

hey guys what about the A9.... you guys dont seem to talk bout the a9 much....