J's Racing ECU installed
 

Hi guys,

I have already posted this topic in Uder the Hood but haven't had much reponse. I am hoping someone here can help me:

I am currently running the following mods:

Mugen CAI
J's header
Amuse dual
stock ECU

I have been told that my car could be running lean in the lower rpm especially just below VTEC that I could be risking damage to the engine.

Now I want to get an ECU which will work well with this setup and not cause any long term damage.

I have been told that the Mugen ECU will not be suitable as it leans out the mixture throughout the rev range and the AMuse ECU is similar.

I really don't want to go down the route of dyno tuning the car as I don't intend to go beyond this level of tune. Therefore I am hoping some of you guys can suggest an ECU that would work well with this setup. I am leaning towards a J's racing ECU at present but I don't have enough information on what it does with the fuel/air ratios.

Any help would be most appreciated :)

Can somebody please help?

:hello:

a good topic! Amuse Boy :) i was thinking the same thing...
I am currently running:
mugen cai
toda header
TS exhaust
stock 04 ECU

i wonder how much I can gain from aftermarket ECU and if its worth awhile. Or else, my other option would be SC. ;)

PC - I am not overly concerned with more gains but more concerned that I may be running too lean with my setup...but now that you mention it - even more power would be great :)

Why not just get an EMS and have it tuned?

Perhaps I'm missing something, but I don't see anything that you've added that would cause your stock ECU to lean out and cause damage to your engine. Simple I/H/E setups shouldn't affect you that much.

You might stand to gain a few ponies from and aftermarket ECU, but if you do, its because it did play with your fuel and timing ;)

BTW, on all these JDM ECU's its recommended that you run 100 octane or higher. I know on the Mugen ECU, it cuts your knock sensor.

Lack of tuners in the UK? But I don't want someone who is not familiar with an S to tinker with it.

Someone posted that the car is taking in more air but the ECU may not be compensating for more fuel in the lower rev range. My car feels really strong throughout the rev range but I want to be running it in a safe manner.

If I were you, I would get your actual A/F numbers before spending the time & money in upgrading your ECU. Is there any reason why you feel it may be running lean? Is you engine making noises in lower rpm? Is it boggish at all?

I believe there is a guy with I/H/E in the Under The Hood section looking at an aftermarket ecu after seeing his #'s (hes in UK too). Maybe you should get in touch with him- https://www.s2ki.com/forums/index.php?showtopic=304973

The car felt fine during a 4 hour drive but after being in traffic, the car did start to bog a bit. That could be related to intake temps though.

Is there an easy way to check if I am running lean - i.e check the spark plugs or something rather than forking out for some elctronic gear?

Thanks for the link though. :)

BTW - what kind of noises am I supposed to hear if the car is running lean?

Edit: after fitting the Js header I did notice a lot more whooshing sound from the exhaust though.

Well the bogging after a 4 hour drive is probably from your intake manifold heating up.

If you don't want to trouble yourself, just go down to a shop that has a dynometer, they will run you car at WOT and give you back your A/F #'s.

Or, you can pickup an A/F meter and wideband O2/lamda, hook it up and see what your average readings are. If you want you can also look at the end of your spark plugs. A whitish/grayish tip means you've been running lean.

Most vehicles running rich/lean usually give off distingusable noises such as "knocking". You would know by now if this was the case.

Did you reset your ECU after your mods?

I didn't notice any knocking or odd noises at all. I reset the ECU after the installation.

So sorry to be a pain but where do I connect the A/f meter and lambda etc?

http://www.plxdevices.com/M-Series-C...ionDiagram.jpg

Here is a diagrahm of the wiring for the PLX units. http://www.plxdevices.com
You can get the M300 (includes display) for under USD 400.

However, this may be overkill if you don't have any future plans for it (i.e. tuning). If you just want to see if you're running lean or not, have a shop do it for you :thumbup:

BTW, read my last post, I editited it (spark plugs).

With the pricing of all the aftermarket units out there, and the fact touched on previously that the JDM ecus may disable knock sensors, and are tuned for higher octane fuels, I'd have to recommend the AEM to anyone who needed an ECU upgrade..

It will upgrade with you in the future - unless you are done now? (yeah RIGHT! ;))
It will allow forced induction
It will allow you to retain your stock ecu, for any number of purposes (smogtime, ebay, etc etc)
It can be fine tuned for your specific car, altitude - everything. Even identical cars from the factory can have large variances.
Local Support Base and user group
Price!

Seems like an easy choice. Plug and play ecus, mail order maps, and trying to get anything optimally tuned from a remote source is going to be a losing battle.. The only downside I see on the AEM is it NEEDS TUNING. The base map is not safe for anything but starting the car up and maybe putting to the dyno facility.

Thanks for the post Rich. :thumbup:

That one downside you mention is what I am worried about. I don't know of any tuners near me that I would trust to tune my car.

I will check if the J's gets rid of the knock sensors etc.

Would the J's ECU not work well with my setup?

I agree with Rich on this one, however if you don't want people messing with your car...I would just pick up a nice wideband unit and an A'pexi VAFCII and call it a day. Thats what i'll being doing!

I'm gonna sleep on it for a bit but I am leaning towards:

1 - Test pipe
2 - J's ECU mapped to my mods - emailed J's Racing - they have preset maps which will suit my selection of mods
3 - Racing spark plugs

Thinks to check:

1 - knock sensors - safety margins
2 - cost!


I just wish people using the J's ECU would chime in.

Thanks for help so far guys! :) WIll keep you posted!!!

I don't think many people use the JDM ecus.. as stated

They are based off 94 octane at the minimum
Emissions controls that are here in the states may not be accounted for
There is no "exchange" - you pay nearly double the list price of an ECU since they don't want or need your core.

VAFCII would be my second choice - simply for the fact that its an easy method to adjust pulsewidth, and you can "trim" the setup yourself, eliminating the NEED for dyno time.. although a good wideband and VAFC and you are right at ~ $1k I would think... Fatten everything up and then gently pull it back/lean it out over runs.

A split second ARC-1 or ARC-2 would allow that adjustment too, but without the wideband you are tuning in the dark...

98 Octane fuel is readily available in the UK so that shouldn't be a problem.

J's Racing have offered a core exchange.

I would go for the VAFC II but with my limited knowledge I'd still be making stabs in the dark.

Thanks for the advice though :thumbup:

Amuse Boy:
read my mods in my sig:
before the Mugen ECU I was running as RICH as stock!
once the ECU went in.. now my car runs PERFECT!!!
Mugen ecu IS a JDM ECU. King's sells it and Mugen does NOT make a different ECU for JDM vs other markets.. required MIN octane is 92 in usa
fuel in Europe is at least 95 by our standards
with the mods you have, a Mugen ECU will do wonders, as Im sure the J's will.
you will NOT run too lean, remember the stock ECU runs rather rich. Just remember regardless of the ECU you choose, you must at least run a cooler fan switch and thermostat, and Mugen also suggests the radiator cap.
I was in bumper to bumper traffic leaving Toronto last week on the 401, for 2 hours.. NOT 1 problem. The other good thing is the Mugen ECU is no were as heat sensitive as the stock, so it reduces the bogging you experienced, I am sure the J's will do the same
defiantely add a test pipe also, will reduce 15 pounds 6kg?? and flow better
HTH's

Marco - I already have the Mugen cooling mods installed. :)

I think I will probably go for the J's racing ECU but I am not sure if I want to remove the cat...

What plugs are you using with your setup?

Thanks

I didn't notice you were in Europe! THATS what those flags are for (DOH)

Then yeah, with the exchange and the octane not being a problem, I'm sure it would work for you!

Stock plugs 41000 miles currently, had 35000 when i installed the ECU, I do not think changing plugs will matter at all with the mods you have and are planning.
You do not have to use a test pipe, But since both ECU's disable the secondary O2 sensor..why not?? Might as well take advantage of all that you are paying for.

With those mods, there is not need at all for an ECU. For one, all your mods haven't opened up your breathing as much as you think (proof, ask anyone, all those mods add up to maybe 10whp).

Remember, There are numerous owners running stock ECUs with Comptech and Vortech Superchargers. Your car is running fine, don't waste the money.

Are you sure about that? The J's alond add around 12whp in the mid range.

Still confused...

If someone dynoed the J's Racing Header alone and got 12whp I def. need one. :LOL:

AB dont waste your money on a EMS "unless" you plan on doing alot more tuning in the future(like me :D )!

You will be fine on the stock ecu "but" if you are really intent on getting something then all you honestly need is either a V-AFC or at the most a Greddy e-mannage.

In regards to tuning and mapping Dan Turner @ Jakan is excellent with most EMS's he used to work for the Mugen race team so knows hondas fullstop! (they are closing down but I'm sure if you called him he would still sort you out :thumbup:

Andy

Thanks Andy! :)

It's looking like I will be going for a J's Racing ECU mapped to the mods I've got. A decat pipe and some cooler plugs.

Don't know much about the decat - do I just screw the 02 sensor into it?

Do a search for a mechanical O2 sensor. I have a test pipe and i have yet to get a CEL. THe mod is something like 2-3 bucks.

Do I need to use that even if I am using a different ECU?

StevenM has previously stated that the secondary O2 sensor is not needed for the Mugen ECU and Marco says at the end of the first page of this thread that its the same for the J's racing ECU.

TBH, I think you are getting carried away with the manufacturer's claims on a lot of these mods AB, alot of owners spend ALOT of money for pretty minimal gains. With that in mind, and bearing in mind that you are not going to go FI in the future or ITBs, an Apexi VAFC seems like a cheap and effective solution from what people have said. However, if you got that route and want to decat the car, simply create a mechanical O2 simulator and buy the anti fouler plugs from HornyHonda who has been selling twin packs of them on the UK For Sale board for a couple of weeks.

CA - it's taken me a year to decide on a manifold so I don't think I make decisions on a whim. J's racing are reputable tuners in Japan and my friend has been talking to the owner of the tuning company itself.

I have sent them a full list of the modifications for which they send the most appropriate mapping.

Okay - so I won't need the O2 sensor connected but what do I do to the sensor itself?

I know you don't buy on impulse AB, its just that I'm a bit cynical about the bhp claims of the companies involved simply because the replacements parts work together so that one person may see 12 whp and another with a different exhaust and CAI will see a couple of whp improvement. However, if I were going for an aftermarket manifold, I would buy a J's too :)

As for the 02 sensor, the conker season isn't that far away :D

AB :what: Your pi$$ing your money up the wall mate, J's are a great company and make some serious stff but "YOU DONT NEED IT"!!!!!!!!!!!!!!!!!!!!

Every car is different and the stock ecu is MAPed so take all that into account you may find as well that J's wont sell you an ECU as they usually want to MAP it to the car and not just send it off which is the same as Amuse(not 100% though) you will get more gains from a piggyback like the e-mannage or even a HKS F-con(various models) "PLUS" if you change your setup in the future you can just get it MAP'd accordingly :)

Andy

You just put the sensor into the hole of the test pipe... Or you can find a bolt that screws into it
it is then attached but it doesnt work because the ECU disables it.

Andy - Thanks for the advice mate but I don't want to modify the engine any more than I have done. My friend has been in talks with the boss of J's Racing and he is happuy to send me a fuly mappped ECU for my setup.:)

Cheers Marco.

I do remember reading somewhere that the sensor can be damaged is it is not screwed in using an anti folwer thing/ I'll probably just remove it and then re attach for MOT tie with the CAT.

dude, just so we are all clear, you are not sending your car to Japan or flying someone over to tune, right? so your custom mapped J's ecu won't really be optimized for your car, right? Because you know with all the variations between motor to motor that a perfect tune from said ecu is impossible, right?

To be honest, I think it's a waste. I know I wouldn't waste my own money on an ecu that cannot be reprogramed and optimized... but it's not my money, and if all you want is bragging rites, for what it's worth, you'd have em...

Not for bragging rights at all. It won't be an absolute perfect tune but then again it will be safe option otherwise why would J's racing offer their ECU.

They have told me to list my mods and mileage etc and they will send me the most appropriate map to suit my car.

I have sent them a heap of questions and am currently awaiting their reply.

I don't want to go down the route of getting a custom ECU as I don't know of any tuners that I would trust with my car.

I suppose I could get the VAFC II but again I am not familiar with tuning it and I would probably need to get my car on a dyno.

My main objkective is to have the car running safely with the mods I have as I intend to keep the car for a while. More power with the ECU would be an added bonus.

Thanks for your help though :)

I have similar mods as you, Mugen intake, J's TB, Mugen header, amuse straight pipe, amuse dual and I have been running the Mugen ECU for 2 years now. The midrange has definitely been improved, there was a noticeable torque increase in the pre-VTEC RPM ranges. I didnt feel too much difference after VETC. Now I am just used to the setup, I cannot compare it from stock.

I raced my buddy with I/H/E setup and I would start to pull on him slowly after the 3rd gear.

Hope this helps a little.

It all helps xpslosiv :) Many thanks

When using the straight pipe - what do you do withe o2 sensor - did you just disconnect it?

Yes, it was what I did. With the aftermarket ECU, the CEL wont lite up.

Dan @ Jakan Honda :thumbup: :thumbup:

Thanks xplosiv :)

Andy - Jakan has shut down now...

I know! but Dan will still be available if you give him a call :thumbup:

Thanks to everyone who helped :thumbup:

I have now ordered:

Denso Iridium IK24 plugs
J's straight pipe
J's N1 ECU

For everyone elses benefit, here are a few questions and answers I got from J's Racing:

What is the VTEC rpm point with J's ECU?
On the map it should be 5,450rpm. But genuine mater have a margin of error depending on the status of use. So it sometime doesn't display like that. If such is the case, please be forewarned.

Is the knock sensor cut?
The knock sensor is not cut. We think knock sensor is absolutely essential for the street user. The genuine knock sensor is very sensitive to the changes in setting and it delays the beginning of ignition fire. If it delayed 10 degree, it down the power lots. Then it decreases by half for the advantage of exchanging the ECU. We change the MAP of ECU and decreases the level of lag of the tide 3 degree.

What fuel should I use?
We recommend High octane, octane rating 100.

And his comments are:
The middle range torque of your current S has powered up because of J's manifold, so if you don't change the MAP, it doesn't have enough safe margin, we think. Therefore, if you change the MAP, you can get safe margin. It has your all range of torque and power improved.

:)

good pick indeed, let us know your impression when you install the ECU.

:)

Good thread AB, think we will need to compare/meet up for a RR day. For the others my car is set up with Mugen cooling Mods, CAI, Manifold, Exhaust and ECU so I have been listening intentley.

I am still a little perplexed as to why they would disable the knocking sensor in the Mugen ECU though, that sounds a pretty important safety feature. If its oversensative why not just change it rather than disable it :thinker:

Octane is another worry for me, reading up on the thread though 98 Octane seems fine I guess?

I ran the Mugen ECU on and off for a couple of years before going with the AEM EMS. It is a fine unit and gives a good increase in performance. Try it.

^damn nice avatar bro!!!

Okay guys - finally got everything installed.

However, the car threw a CEL.

Now I have the test pipe fitted but I didn't connect the secondary o2 sensor - I just unclipped it and disconnected it. I would have thought that J's would have cancelled the secondary o2 sensor.

That way, each year, all I wouild need to do is connect the cat back and then clip the sensor back on.

Anyway, when I disconnect the battery, the CEL goes away but then returns once the car is started.

I have a strong feeling that the o2 sensor is causing this:

I have two options:

1 - sned ecu back to get o2 sensor circuit disabled
2 - use an anti fouler plug thing

what would you recommend i do? I can get the ECU back to me within 10 days! And won't cost me extra as I am already posting stuff to Japan.

Is it a good idea to leave the sensor clip exposed to the elements? Could the pins rust?

Be brutally honest guys... :)

spark plug fouler... do NOT leave the sensor out in the open without anything covering it... it will be garbage...

Veilside - When I say I unclip the sensor - I mean - I leave it screwed in the cat and unplug it from the tranny - the wire is only a foot long and I could reach the connected and just unplugged it. Are you saying the connector would be garbage too if left exposed withour the other end connected?

Why do you need an anti fowler, why not plug it straight in?

if you buy 2 antifoulers, you drill one out, screw them together, and put it between the sensor and the cat/testpipe... no more CEL because it pulls the sensor out of the direct exhaust flow...

Amuseboy, you could cover it with electrical tape, but I wouldn't do it to something that hangs underneath the car, especially if you ever get caught in the rain...

Because it would throw a CEL as the gasses are not being filtered by the CAT. An anti fouler plug would keep the sensor away from the direct air flow so that it doesn't throw a CEL.

I could be wrong but I think you can also damage the sesnor. I think the Mugen has the secondary o2 sensor cut so you could just unclip it by following the wire.

Just seems the best place to leave it, there are two sensors one before and after, I asume there both the same. I'll raise my own thread rather than hijack yours and see what the guru's have to say ;)

You can use this if you like TM.

The first sensor in the manifold montiors the air fuel mixture. The second one only monitors the emmissions/.

Cheers boss ;)

Ben at AJR has informed me that it will not be the secondary o2 sensor causing the CEL but the air pump system as their is no sensor on the ECU - JDM.

Does anyone have any more thoughts on this?

I really don't want to have to send the ECU back and then get a UK ECU modified which would have all the circuits but then I would have to get a key programmed to start the car...

:banghead:

Seems a small price to pay for an imoboliser, besides I know Jorge would oblige. He seem'd pretty excited about the idea of an aftermarket ECU.

TM - the immobiliser is the last of my worries - I have ample security on the car. I am really hoping that the car runs with the o2 snesor without a CEL in th edash. :)

has anyone with h/e/i/ ems went for a dyno run? what are you guys making.

I'm sure people have and have had great results... :)

But I am hoping someone can enlighten me about the CEL with the J's Racing ECU. :0

:thumbup: for being risky and trying something new.

That said, I believe this is a total waste of money and huge headache. With your mods, the car isn't running bad at all, its running better. Everyone says the ECU gave their car better mid range and smoother running, but I've yet to see a Dyno Chart proving so. If I were to ever do any ECU work, it'd be EMS. But since my car is staying NA with essentially all boltons, this is no concern of mine. Once again, the JDM bandwagon is raping you I believe, when it comes to custom tuning to your car and its setup, your calling Japanese people in Japan that speak Japanese and trying to explain to them what you want, when AEM offers the EMS in the U.S. and is probably one of the best systems in the world. :confused:

Good Luck and I hope everything works out for you.

I would try the anitfouler. It will not hurt to try it. I think its like 3 bucks at your auto store. It will just fool the sensor thinking that its stock...it seems like the members here w/test pipes that have installed this modification, was like 95% sucess, but this was w/stock ECU. Remember to use the two antifoulers that came with it and not one. I have a gut feeling that the J's ECU will do the same.

I've been searching and there were couple of threads about this Cel situation something like O2 Sensor. Sorry don't have the link but theres' like two major links.

I'm just waiting for my T1R test pipe and I"m going to go to the anitfouler direction.

I asked Ben when the J's AP2 ECUcoming out. And if I can recall, there testing it??? Don't know for sure though. This was a while back.

I have almost the same set up as you:

J's intake
J's header
T1R test pipe (its on its way)
J's Tit. 60RS.

And yes I'm very interested in the J's ECU. I would do the anitfouler. That would be my last option.

Also I would recommend (if you don't have it) is the grounding kit. I recommend the V-power and AJR ground wiring kit. (There all precut to its length). That give another untold and can't explain, but something like 5hps...but for sure makes your care run a bit smoother, even the radio sounds better, just can't explain it. :confused:

Keep us post if anything. Good Luck!

Thanks for tha dvcie guys :thumbup:

I will be trying the anti foulers as soon as I receive them.

Blue - I already have a gorunding kit which was very expensive but I have yet to install it.

One other thing to mention is that I had to ground the fuel pump relay wire and now when I put the ignition to on, the pump stays on until I start the car - whereas the stock ECU pressurises the system and then switches off. Any thoughts on why it continues?

Because you didn't install the Mugen ECU :D

Sorry, couldn't help myself, had to be said going by the history of problems you have had setting this unit up :(

I dont have any words of wisdom for you AB so sorry for that :(

But I do want to say mucho respecto for doing this as someone has got to be a first person to do it and sort though all the teething issues, which makes way for other people to take the leap after learning from your mistakes ( I know alllll about that )

Although the dash only shows a cel if it receives a signal from the ECU so can you not get a code from the J's ECU with a code reader?

Andy

You still want those plugs? :LOL:

Spoke to my mate in Japan - the response from Mr Uemoto (J's Racing):

1 - secondary o2 sensor is not cut from the ECU
2 - air pump should not affect the ECU CEL


Anyway, many many many thanks to Mark_m, I received teh anti foulers plugs the very next day - I bored out one of them to 1/2 inch or around 13mm.

I then attached the o2 sensor to the anti foulers (used a bit of anti sieze) and then tightened to the straight pipe. (battery was disconnected during the install)

I plugged in the sensor and connected the battery. Fingers crossed and fired her up..................................






















ALL IS GOOD. CAR PURRED NICELY. NO DREADED CEL. CAR STILL STANK!!! SOUND IS A LOT DEEPER! AND I AM A LOT HAPPIER!!!!!!!






Thanks to everyone who has helped! :) :rev:

Cheers Andrew - the ECU is a rework of the stock ECU - optimised AFRs and a less paranoid knock sensor circuit. Lower VTEC crossover and higher redline :D

Car is now working perfectly!!!

Can't wait to see your next project ;)

I know ;)

I cant wait to see my next project either :D