DC5 : ECU compatibility

[EK4R]

couldn't find what i wanted in the Technical section (went through 31pages of it last night lol)

anyways just a quick question for a friend

if i were to transplant a jdm k20 would i need a jdm ecu or can ausdm ecu run it for now? eventually going Kpro.

dont want to fk* up the engine

also with regards to the swap, any harness/wiring issues i am looking at? or a straight swap for a ausdm dc5

cheers

[Chi]

JDM Engine better off with JDM Ecu.

Redline/Cut out is higher on JDM as well so putting the AUDM Ecu will limit it.

And im sure you can use audm ECU because of immobiliser?


As far as i know the Engine should be a straight bolt in into the DC5.

[EK4R]

thanks chi.

just did a quick search on clubrsx also.

i was reading only the AUSDM ecu with the code Q on the chip inside could run jdm k20s, also if i were to Kpro it, i would need a ausdm code Q to do so or a jdm ecu

this correct?

[air23box]

its just a straight swap between the 2 engine George......but due to the fact that we dun have good quality fuel.....The difference running a AUDM and JDM ECU are minimal....of coz if you can get a hand of a JDM ECU that will be better......the other benefit is as what chi mention.......for the Kpro question.....I think you can get some better idea from other members with previous experience or do a search in CRSX.....hope that helps...

[Evatec]

The JDM DC5R ECU has a different pinout for the fuel relay compared to the AUS DC5R and North American DC5S. The later two are the same. Can be simply modified internally in the ECU to overcome this small issue. A 2 minute soldering job.

Now, after this simple modification, a JDM DC5R ECU works well in an Australian DC5R. Don't worry about the JDM DC5R ECU being more agressive than the Australian ECU or worry because the Japanese DC5R runs 100 octane fuel. The Australian model has a lower compression ratio than the Japanese version. 98 fuel is fine with a JDM DC5R ECU in an Australian model. The JDM DC5R ECU shifts the rev limit to 8700 RPM and definitely makes the car pull stronger from 7500 onwards.

Since I experimented with the initial modifications as mentioned above a couple of years ago, I have since modified an Australian ECU (with K-Pro installed as well) so that it runs in either an Australian or Japanese DC5R car. I can simply swap the modified ECU from one car to another. (NB. I own an Australian DC5R car as well as JDM DC5R vehicle)

If you are swapping a JDM DC5R engine into an Australian car and use the JDM DC5R wiring harness, probably no need to modifiy anything if you run the JDM DC5R ECU as well. Likewise, if you use an Australian wiring harness and an Australian ECU with a JDM DC5R engine, that also should work without having to modify anything.

Hope this helps a little.

[EK4R]

sweet thhanks for all the help guys. think im cleared

last quick qns regarding KPRO. best to KPRO the jdm ecu or ausdm ecu if i were to sell the car later as stock with the jdm k20. (provided i have both ecu)

[EK4R]

btw EVATEC, there was a thread you stated that the jdm flywheel is of different part number to the ausdm one.

do you know roughly the weight of both the flywheel? wondering if its worth transplanting the gearbox over also for the lighter flywheel (if it is lighter) and maybe a newer clutch compare to the current older ausdm gearbox

[Evatec]

sweet thhanks for all the help guys. think im cleared

last quick qns regarding KPRO. best to KPRO the jdm ecu or ausdm ecu if i were to sell the car later as stock with the jdm k20. (provided i have both ecu)

Really doesn't matter which ECU you K-Pro. After fitting a K-Pro to the ECU, it's the mapping that then affects the tune and how the ECU and car performs. If you were to sell you car later as stock but with a JDM K20A engine, better performance is afforded by using the standard JDM ECU.

[Evatec]

btw EVATEC, there was a thread you stated that the jdm flywheel is of different part number to the ausdm one.

do you know roughly the weight of both the flywheel? wondering if its worth transplanting the gearbox over also for the lighter flywheel (if it is lighter) and maybe a newer clutch compare to the current older ausdm gearbox

Yes, the JDM DC5R flywheel is lighter than the Australian DC5R. I just couldn't find the weights of both off hand. I have a spare JDM one in my garage at the moment, but not an Australian one to weigh and compare.

The gearbox in a JDM DC5R is the same as the Australian gearbox. Same ratios exactly. The JDM clutch appears to have a heavier feel (stronger pressure plate) when I jump from one car to another.

Surprisingly how good both clutches are and how much extra power these clutches can take. If you are drag racing alot, then a stronger clutch would be a consideration.