Using a tuned ECU on a stock setup

[stEEZE nikkAA]

What's up guys, currently working on an s13 with an autotragic SOHC. Just picked up a ka24de along with a 5 speed trans with everything needed for the auto-manual swap. Picked up the ECU from the guy while I was at it. He was running a T3/T4 turbo on 8 psi. His ECU was tuned at the shop for the turbo setup. My setup will be a stock ka24de with a 5 speed, and will not be slapping on a turbo yet. I've been told that I can work around the tune and just use the ECU, but I have also been told that I have to get it reflashed. Is it possible to just run it with the current tune that it's on?

[cdlong]

I wouldn't suggest it. It could theoretically blow up your new engine. At best it would run like shit, at worst, not at all. Depending on what ECU it is, you might be able to reset it to the stock map, or if you do have to send it in, they shouldn't have to charge you the full remapping fee. What injectors did he run? Running 270s on a map for 480s is a recipe for disaster. 8 psi isn't much though, if it was the same size injectors you might be ok, it'll just run crappy.

[stEEZE nikkAA]

Not sure what injectors he was running. It's the stock p28 ecu

[lok]

Just move the jumper back so it will run on the stock bin.

[stEEZE nikkAA]

Not really sure what that means, can you explain?

[cdlong]

Not sure what injectors he was running. It's the stock p28 ecu

I meant who was the ECU modified by, JWT, enthalpy, etc. If you knew that, you could contact the company or read their install instructions to reverse it.

It may depend on the ECU, but Lok is probably refering to the process described here: http://zilvia.net/f/engine-tech/270095-nistune-information-guide-how-tos-guide-you.html#post2942248 Just scroll down to this part.

The last soldering step is to remove the resistor at position R021 to position R020, this tells the ecu to access the Nistune board instead of the normal ROM.

Though jumpers typically don't require soldering so you really should find out what you're working with. Maybe crack it open and post some pics.

[GroundPerformance]

SHould be all the same for all S13 except SOHC which is 8 bit single chip. All you have to do is locate the Jumper switch CJ1 and CJ2. If you have a daugtherboard then you CJ2 closed and CJ1 open. Just reverse it and it will switch it back to stock OE BIN Operation and bypass the board all together. You can even leave the board there. Below is the pic for reference. BTW P28 is a Honda ECU code hopefully its just a typo.

http://i627.photobucket.com/albums/tt352/cleantune2/carandstuff/IMGA0904.jpg

[besTint]

keep it simple. just get a stock ECU. shouldnt be hard to find.

[stEEZE nikkAA]

Here's the ecu. I'm assuming that the yellow board is the daughterboard that they put for the tune? So.. like GroundPerformance said, I desolder the CJ2 connection and jump the CJ1 connection?

http://a7.sphotos.ak.fbcdn.net/hphotos-ak-ash4/312401_2324477108377_1143111482_32771055_7829652_n .jpg

http://i37.photobucket.com/albums/e71/Lube716/IMG-20110823-01197.jpg

[lazysk8er2]

im not a whiz at this but if he popped out both of the chips from the yellow daughterboard will it still run the car at stock mode