So the s5 jspec engine I received has an ecu tuned by knights sports Japan. The engine had all kinds of aftermarket **** on it. It had dedicated sources for atmospheric bov and boost controller.

I would like to use this ecu, but i know it wont agree with the dash harness of my car. So, I would like to put this tuned chip into a usdm ecu.

Can this be successfully done, or is it a waste of time?

 

waste of time, chips are tuned to the setup of the car. if you change anything then it will be worthless without knowing exactly what it is tuned to run. even then the tunes are very conservative and hardly worth the effort of salvaging.

 

Well since the chip was tuned for my engine, why would it not work?



Same turbo, same type of fmic, bov, fuel injectors, cas.... im assuming he still was using the maf still because the reduction boot (whatever its called) was left on the turbo inlet...

Everything is the same as it was in japan.

Why would it not work

 

A jspec ecu will only work when chipped otherwise the engine will run on one rotor...knightsports chip is fine most likely it is a generic chip some of them are rom tuned. My knightsports ecu ran my car nicely but have since switched to megasquirt. Hope this helps

 

if you wanted an answer you got one, otherwise if you're not really asking a question then just do it and figure it out for yourself.

 

I did ask a question. The question was why will it not work.

One guy replied and said it worked fine.

You say it doesn't.

Who am I supposed to believe?

 

ever consider which engine harness you are going to use?That may play a factor.
I hate wiring,but isn't the USDM harness different than the JDM harnes..so if the engine was running on the JDM harness "in Japan" then it may not run correct on a USDM harness in the "Good ol USA".
If I am wrong,ok..I accept it.no big deal..just an observation though.

 

1. if the difference between the US ecu and the JDM ecu is the software, how does swapping the chips help?

2. if the only thing that changed between here and japan, is the wiring harness, than the ECU won't fix your problem

and

3. the chip removes the speed limiter fuel cut, so the JDM ecu should just work.

 

Why won't it agree with the dash harness? Are you trying to put the S5 chip into an S4 ecu?

To use the ecu, you'd have to confirm every wire is hooked up correctly. That means matching the wiring between the usdm wiring diagram and the JDM S5 wiring diagram. The problem is that the latter diagram does not exist in electronic form.

Could it work? Yes.
Is there any way to definitively say it will work without actually trying it? No.
Is the risk worth trying to cut corners with an ecu? Personally, No. But that's up to you.

 

when did i say it wouldn't work?

i said it may work but it surely isn't optimal even if it was chipped for the setup of the car.

normally JDM ECUs get put on a shelf and collect dust, most people simply do not bother with them due to the wiring/programming discrepancies. no one in japan cares to translate the ECU pinouts into english so we have no idea how the JDM ECU is wired and they cause problems with USDM cars, swapping the chip may work, it also may just be a waste of time.

 

**** it. Im gonna take the easy way out. Jus bought a oem ecu.

Thanks for the input.

 

No.that is the Smart way out.
the "easy way out" would be "Screw this" and sell the car!

No dedication+no Motivation=zero admiration!
and da ladies like a guy that can stick to a plan..lol..and has hot wheels.!

 

just get the rtek chip in the stage you need, then you know what you're getting

 

Changed my mind again. Gonna try to rewire the s4 dash harness for the s5 jdm ecu. Found a jspec wire diagram. Very similar to the usdm ecu from what I can see.

Drawing it all out right now

 

So heres what I got




Heres my jspec pinout reference

Thanks to google japan

 

well if you get it to work i'm sure people would be interested to know your findings. the S5 370 ECU is gold plated now and usually they are either very difficult to find or cost upwards of $175.

the N352 and N353 ECU can be used in a pinch from the series 5 vert but it isn't ideal. it doesn't like the 370 pressure sensor and the 350 pressure sensor doesn't adjust timing after 0psi and usually throws it into default map reading for a faulty pressure sensor(it tends to whig out when throwing 13psi of boost at a vacuum only calibrated sensor). but i did manage to scrape out 230whp off a stock turbo/intercooler with the N352 with just a piggyback to add in fuel at 11psi/6k with a 6 port block.

most people use them on stock transplants, i think i'm one of the first to try and squeeze it but the owner inevitably opted for a haltech instead to make it more reliable. the results with the vert ECU on a boosted engine were quite limited.

i've simply never trusted chipped ECUs unless it was stock mapped like the Rtek to calibrate for addons/deductions but not for power. power tuning should be done with something that you can physically adjust versus rely on blindly thinking that a chip is safe.

 

rteks are for power too but you cant really tune it unless you get an safc, I've personally got.an rtek 1.7 running a stock s5 Turbo with full exhaust , walbro 255 , 550/720s.

I haven't gotten past my breakin , but once I do ill see what my wideband reads, I plan on 10-11psi on the stock tmic and airbox , I shouod also be installing a aux.injection kit.

 

by power i mean 13+ psi, Rtek does not really support that but simply unlocks some additional potential by upping the fuel system limitation for added boost. a stock car is really only limited to about 9psi before the fuel system begins to reach the end of its scale.

 

rtek 1.8 probably can with the 720/720 injectors but I'm not.sure how much HP that setup.can handle.