RomRaider

Hi Guys,
I have been reading up on tuning for a while now and have been trying to resist flashing my Stock MY04 JDM LGT (5EAT) with the stock values from the MY04 JDM LGT (MT) ROM. Rightly or wrongly, I have gone ahead and done this and am now paranoid that I am going to damage something. I have included a log and learning table from the first drive after the reflash, if you can take a look for me and make suggestions it would be very much appreciated. Fuel, 95 Octane. Atmospheric pressure 1.01 Bar (~14.6 PSI)

Potscrub
New Zealand

Note: I have also put on my pre flash learning table, car is totally stock and has never had any previous ECU manipulation (by me at least).

Here is another log and learning table, it seems to be settling itself down but it has reported knocking between the 2000-3000RPM range. Is this acceptable?

Any reason you decided to flash the MT version of the ROM over your AT ROM?

I probably don’t have a valid reason other than I believe that the JDM AT is 191kW but the JDM MT is 206kW - they have the same torque of ~340NM and use the same engine (again this is my interpretation). I really wanted to have those extra 15kW and I want to learn more about tuning vehicles as I have always had an interest in this type of thing. It is pretty fascinating stuff and I really enjoy reading threads like your one here topic3678-90.html, in fact this is what twisted my arm to just go ahead and do it.

Those extra 15Kw are probably just from having the MT, and less drivetrain losses.

The advertised Subaru numbers are crank so it has nothing to do with driveline losses. In the US, the 5EAT and 5MT make the same crank hp. USDM cars use the same turbo.

I think it has more to do with the turbos. At one time, I had both the VF38 and TD04HLA-19T-8.5 on my workbench. There's no doubt that the MHI turbo is larger. The 04 JDM 5EAT uses the VF38 and the 04 JDM 5MT uses the MHI turbo.

Thanks for the info guys, is it fair to say that my theory is flawed? I didn't actually flash the MT rom over the AT, I just changed the tables for boost, AVCS, Wastgate, timing etc. Do my logs show that the moderately increased boost levels were safely reached even though the turbo is not the same as the MT? Also, has the VF38 got any extra capacity than what is achieved with the stock setup? My engine code is EJ20 XDKAJE, I do not have a service manual that I can read so I can't decipher the description.
Cheers

If you keep driving with that tune, I think you'll cause some erosion on your pistons. The small turbo + conservative fueling + knock control should probably prevent the car from detonating.

Just tune it like any other car.

I have the Australian service manual for the 05 JDM LGT. What kind of info do you want?

Do you have the ability to do a lot of logs? I wouldn't mind setting up a Stage 1 JDM LGT. However, your car should be completely stock except for a transmission cooler. New (or newish) air filter and fresh oil change. No intake or exhaust leaks.

Some people have gotten away without using a transmission cooler, but I highly recommend it for all 5EATs. A new 5EAT is expensive and a transmission cooler is very inexpensive.

You can start by reverting back to your stock rom except change the WGDC tables to ALL ZEROs. The car will be slow, but it will allow you to set up your car for complete tuning. Then drive around and try to keep constant throttle. Drive as fast or as slow as you want but try to minimize sharp throttle movements.

Then do a 3rd gear wide open throttle log and log the following from 2000 rpm to redline:

rpm
load direct (g/s)
AFR #1
MAF (g/s)
manifold relative pressure (psi)
knock sum
ignition total timing
vehicle speed (mph)

Do a learning view before and after the 3rd gear WOT log.

Write down ecu atmospheric pressure and ambient temperature.

Post your rom too.

Thanks for the heads up Mickeyd, I immediately reverted back to stock.

Is the service manual in electronic form?

I have a full warranty on my car, I wonder if a transmission cooler would void that? What driving conditions would necessitate a cooler, I am not normally a spirited driver. I have probably only had one good driving session in the last 6 months.

Yes LGT is totally stock - no exhaust or intake leaks as far as
i am aware.

Lots of logs.... Work takes me overseas a bit, but there would be a bit of time after work most days. I am pretty keen to give this a go, but I don’t want to stuff you around with my erratic schedule. I will do the ROM adjustments and log the data this weekend, if you have an interest and have time then it would be awesome if you could take a look at it, if not then let me know and I can just revert back to stock.

Thanks for your help.
Cheers
Rob

any progress with JDM LGT ROM?