LS3 E38 OS - auto vs manual trans

[eboch]

Hi All;

Hope someone knows about this. In trying to get my DFCO working on an LS3 swap, I seem to have a condition where the E38 doesnt read the VSS inputs (on pins 71 & 72) from my Tremec. [I think] because of this, the E38's DFCO doesnt work.

My LS3/E38 combo is out of an '08 corvette with auto trans. i noticed that pins 71/72 on the E38's connector were blocked off. I unblocked them, re-pinned them and connected them directly to my Tremec 5sped (TKO600). I dont have a TCM. The E38 shows 0km/hr all the time. I've checked the VSS sender, and VSS wiring .. .all seems OK.

I've read elsewhere that the E38 OS's are different for auto & manual trans ... and I'm thinking maybe I need to load a different OS in. The question I have are;

1/ is there a difference between an auto and manual trans E38 OS? (I know the tunes and tune-configs are different
2/ when I load a new tune in and do a "write entire", does the OS of the tune I'm writing in also get written in?
3/ if I need a different OS, where can I get that? can that be downloaded from a manual-equipped LS3 corvette's E38?

Thanks
eboch

[kgraves]

Yes, there is a difference between an auto and manual OS. The auto OS uses different pins in the ECM for the VSS if I remember correctly. You will need an MDI2 device and use GM SPS to reprogram your E38 to a manual OS since HPTuners doesn't have the ability to. This is because the ECM file has 8 segments but HPTuners only has access to 6 of these when you use the write entire flash.

[eboch]

kgraves;

Thanks for this info. Sounds like I cant do this with HPtuners. Under "OS" in HpTuners ... there is a "apply code modification" function .... sounds like this wont do what I need it to here.

I assume the MD12 and GM SPS equipment is something that my local dyno shop would have ... I'll investigate.


Cheers
eboch

[blindsquirrel]

First, you need to find a sample file of the same year/make/model but with a manual trans, and copy the VIN that vehicle used. Use that VIN to program it in SPS, it will pull down a calibration the manual trans vehicle would've used. You can't re-use your current VIN as that will just get you the same auto trans calibration again.

[eboch]

First, you need to find a sample file of the same year/make/model but with a manual trans, and copy the VIN that vehicle used. Use that VIN to program it in SPS, it will pull down a calibration the manual trans vehicle would've used. You can't re-use your current VIN as that will just get you the same auto trans calibration again.

[eboch]

BlindSquirrel;

Thanks ... good info (that I didnt know). I'm wondering if this is something the local GM dealership could help me with.

Cheers
eboch

[blindsquirrel]

For about the same money and less hassle you can buy a used E38 of the same service number pre-programmed to the VIN of your choice. Either way it will have to be relicensed in HPT because it'll be a different VIN.

[eboch]

For about the same money and less hassle you can buy a used E38 of the same service number pre-programmed to the VIN of your choice. Either way it will have to be relicensed in HPT because it'll be a different VIN.

... yes .... but I dont have a VIN # from a suitable 2008 Corvette LS3 which came equipped with a manual trans ...

[blindsquirrel]

You have a HP Tuners account? You know how to get to your customer page? And from there to the tune repository? And then search for 2008 Corvettes with manual trans, and find one with the same engine size, and open the downloaded file, go to tune details, copy/paste the VIN shown there?

[eboch]

You have a HP Tuners account? You know how to get to your customer page? And from there to the tune repository? And then search for 2008 Corvettes with manual trans, and find one with the same engine size, and open the downloaded file, go to tune details, copy/paste the VIN shown there?

I've purchased an ECU with a Corvette LS3 manual-trans factory tune. We'll see how that works out.

I'll post info later.

Cheers
eboch