I was after any info on the differences between the J-spec, Aus-spec and USDM ECU's. I do realise they have different closed loop timing maps and that is mainly the reason I am trying to source a new ECU at the moment as a replacement for my current j-spec one. Mainly my question is - does the j-spec ecu have more advanced fuel/timing maps during 'open loop' or (normal operation) than say a aus-spec or usdm ECU would and further to this - does anyone know what the big numbers on the ecu's of the early 89/90's zed's represent? Have managed to source a secondhand usdm ecu (direct match - NA 5spd) and am just wanting to make sure it will work ok in my car and ok with australia fuel etc etc. It has the number 20 on it. .. From reading on old threads I get the impression I might be loosing abit of power in open loop operation without the original j-spec ecu in anymore..? Any knowledge/info much appreciated! Cheers
If you are worried about the fuel maps, why not buy the USDM ecu, socket it, and get someone to burn a NA 5 spd stock chip for you? If you were looking for a tt chip, I have plenty, but I don't think I have any NA chips. I'm sure the AusDelivered NA owners can help you out at very little expense. EDIT: Also AFAIK, you can use an automatic ecu in a manual, but not the other way round.
answers for you.... The J-spec and aus-spec ecu are identical in all area's except one. Between the 2000-3000 rev range, under light throttle, the J-spec runs more advanced timing. In some area's up to 4 degree's above the aus-spec ecu. However, the fuel maps are identical in all aspects between aus-spec and J-spec... The problem this causes for some NA owners (do a search on my name)is that the extra timing without the addition of extra fuel has caused pinging problems for some of us NA J-spec owners. Obviously, the japs have better fuel than us and this isnt a problem for them.... however, this is only a small number of cars and even some aus-spec zeds have had small pinging issues in that area... Also, the auto ECU runs slightly more advanced timing in the same area over the manual ecu. This I can only confirm for the aus-spec ecu's, not J-spec... Cheers
Re: answers for you.... Thanks Jedi. Will this mean that the aus-spec and the USDM ecu's are identical?
