tuning an LS3 on an LS2 ECM

[LeftLane]

I recently replaced the LS2 in my '06 GTO with a 2009 LS3 from a C6, assisted by a TRG-002 translator from the fine kiddies at Lingenfelter (thanks Keith, if you're in here somewhere...)

I've had to deal with some bugaboos and gremlins caused by the installing shop (various leaks and damages done), and with everything fixed now its time to get this thing tuned. I hate to mess with it because I've been getting outrageous mileage on the highway (over 30mpg!), but the city digits are awful and I'm sure in time the motor will eventually show disgust at the stock LS2 tune and cause me more problems.

I'm debating either tuning this thing myself (I have experience as a DFI EMIC), or finding a tuner in Florida to do it. If I decide to try tuning this car, am I walking into problems? Is the translator box going to cause issues with the tuning software? Right now the motor is stock - should I look for a stock C6 or G8GXP tune to hold me over until I get some LT's on there?

And where on this website can I buy the software? The link under "Products" just shows how I can purchase additional licenses, no word on buying the actual software and first license.

Also, everyone around my area is into HPTune, so how do the two packages compare? I'm tool-agnostic, so I'm just looking for a feature comparison, not a holy war. I'm here in the first place because I like to do things against the herd, so I'm open to your info.

[joecar]

Hi LL, welcome to the forum

The 58x->24x box should not cause any problems with tuning.

(in general, unrelated to tuning, various people have mentioned to keep the box away from engine heat)


If you have experience with Accel DFI EMIC, then download/install the EFILive V7 software from here;
then download a 2006 GTO LS2 PCM file from here and use the software to look over the tables.

Having a look at the software would be the best indicator to determine if you want to do it yourself.

Doing it yourself, you would be doing this:
- copying/interpolating the injector tables (B4001, B1201-17 in the search box);
- copying the spark timing tables (B5101,2, B5120);
- copying various other tables;
- using a wideband to correct the VE table (B0200) in OLSD mode;
- using a wideband to correct the MAF table (B5001, B2001,2) in OL mode;
- manipulating various other settings.

At EFILive Online Store see here. It might be easier to buy from a dealer/reseller in the US.

The two packages are similar, same features other than:
- HPT covers more vehicles/models/years,
- EFILive lets you swap OS's and transmission segments at will (if compatible with PCM),
- EFILive has black box mode (logging and flashing), not necessary to bring laptop to car,
- EFILive has serial comms (RS232) connection to various widebands (i.e. lambda in serial/digital form, avoids analog offset problems),
- EFILive user interface is oriented more toward the technical personality.

One or the other may have a few extra tables defined.

And the scantool is just phenomenal.

Of course, here, we'll tell you that EFILive simply rocks, and it really does, period.

Going against the herd is good (that's what Galileo did; that's not what lemmings do).

[gmh308]

Are you running the stock MAF and O2's?

If so, all you really need to do is get the injector flow rates from their LS2 IFR's up to about 5.25 g/s or 42lbs/hr. After that you can optimise timing etc as Joecar points out.

You are directly above the centre of the earth, and so am I, so we are in the same place but I cant see you .

Try Chuck at Corvettes of Westchester NY for EFILive.

[LeftLane]

Definitely stock LS2 MAF and O2 sensors (I think those parts plus the TB are all the same on the LS2/3). I'm using the LS3 injectors though, so is there a setup or config table where I can enter the new injector values or do I have to go edit all the cells? I haven't downloaded the software yet to play with it. DFI is a little different than EFILive, obviously. With DFI Calmap, after entering basic stuff like CID and injector size, I lay out my Target A:F, and then the ECM does corrections to get the A:F to match. I go in to my VE tables and adjust the fuel at different load until the corrections go away, and then I interpolate the whole thing. Usually can get everything to look nice within 4-5 pulls, or if a dyno isn't around, install the DFI WB kit and go for a road tune.

[LeftLane]

If you have experience with Accel DFI EMIC, then download/install the EFILive V7 software from here;
then download a 2006 GTO LS2 PCM file from here and use the software to look over the tables.

So I should download the stock LS2 tune and edit it with LS3 values? So I shouldn't just go for the GXP or Vette LS3 tune and overwrite it?

[joecar]

So I should download the stock LS2 tune and edit it with LS3 values? So I shouldn't just go for the GXP or Vette LS3 tune and overwrite it?

You could, but the two ECM's may not be compatible, one might be an E40 and the other an E67/E38 (I'm not sure which)...

If that's the case then you would have to manually copy the tables.

[LeftLane]

Right now I remember. The GTO, according to the dealer tech (almost an oxymoron, I think) was unique in that it had very complex body electronics, and installing anything other than the proper ECM would result in a non-functioning car. I imagine there is code in there that checks for all that.

So, copy and paste it is!