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Noob needs help with L32 swap into GT



I've got the instructions that came with my HPTuners sitting right in front of me-- it reads:

CAUTION To avoid damage to your interface, only power the laptop with a fully charged laptop battery. Do not plug the laptop into another power source. The HP product obtains power from both the laptop and the vehicle. This causes unique issues when there is a voltage offset between the two voltage sources that can cause catastrophic failure. Do NOT utilize a DC to DC converter to power the laptop as doing so may cause damage to the interface of the vehicle that is not covered under any warranty. Damage to the interface or the vehicle that is caused by a voltage offset is not covered under any warranty.

Didn't seem worth it to me to chance it so I got a new battery for the laptop. If I download both the 02 GT's pcm and my OverKill pcm, then use the comparison log to overwrite the Gt's engine tune with the OverKill L32 engine tune, and keep the GT's tranny tune and change the system(fan) and speedo values to the OverKill as well.--- should that be good to go? Or are there other parameters that need to be redone?
 
Now that I`ve made the new file/tune of my OverKill engine tune and GT tranny, when I go to flash it, do I use 'Write Calibration' or 'Write Entire'? And should I be flashing the GT's pcm or do I need to use a GTP pcm to get the 2 bar map recognized?
 


sugaryuk said:
Now that I`ve made the new file/tune of my OverKill engine tune and GT tranny, when I go to flash it, do I use 'Write Calibration' or 'Write Entire'? And should I be flashing the GT's pcm or do I need to use a GTP pcm to get the 2 bar map recognized?
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i would use the gtp bin file because of the map sensor. [ut the na trans file in the gtp bin. id do a full write too. the pcm dont matter really, unless its not a unlocked vin. if you got the year unlocked it should be no issue.
 
sugaryuk said:
Now that I`ve made the new file/tune of my OverKill engine tune and GT tranny, when I go to flash it, do I use 'Write Calibration' or 'Write Entire'? And should I be flashing the GT's pcm or do I need to use a GTP pcm to get the 2 bar map recognized?
Click to expand...

You should use the GTP pcm because Overkill may have setup tables that HPT won't let you at to copy over to the GT pcm (i.e. you need to use TinyTuner). Plus if you use the GTP pcm, you should only need to do a "Write Calibration".

I have never used the "Write Entire" option but I know someone else who did and the pcm end up bricked because the car's battery wasn't fully charged.
 
I seem to recall being told that the OK pcm was unlocked-- so does that mean I don't have to worry about the VIN being changed to the GT's? It seems that way because it's currently in the GT and it's running--and as we don't have any vehicle testing up here anymore do I even need it? I guess that means I'll have to blow 2 more credits to tune the 03GTP pcm, currently just have the gt license (not the entire year). Does it make sense to try just a Write Calibration and see if that works, before attempting a full write (read a few horror stories of people screwing up pcms after doing full writes).
 
sugaryuk said:
I seem to recall being told that the OK pcm was unlocked-- so does that mean I don't have to worry about the VIN being changed to the GT's? It seems that way because it's currently in the GT and it's running--and as we don't have any vehicle testing up here anymore do I even need it? I guess that means I'll have to blow 2 more credits to tune the 03GTP pcm, currently just have the gt license (not the entire year). Does it make sense to try just a Write Calibration and see if that works, before attempting a full write (read a few horror stories of people screwing up pcms after doing full writes).
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Ya, HPT credits...what else you gonna do with them? Have you read the OK tuned pcm and saved it?

I don't know if you need to update the VIN in the OK pcm. If it sets off a security code/lite or the radio and things don't work, then I guess so. I would try running it with the OK tuned pcm as is. The GT trans is 3.29 geared like your old setup. Not sure if the valve body difference deal matters in this swap. What about test-running it on jackstands?
 
bcmonzai said:
Ya, HPT credits...what else you gonna do with them? Have you read the OK tuned pcm and saved it?

I don't know if you need to update the VIN in the OK pcm. If it sets off a security code/lite or the radio and things don't work, then I guess so. I would try running it with the OK tuned pcm as is. The GT trans is 3.29 geared like your old setup. Not sure if the valve body difference deal matters in this swap. What about test-running it on jackstands?
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Made sure I saved both the OK tune and the GT's stock tune. I've actually been driving around a bit with the OK pcm and it seems to working fairly decent, tranny shifts are more firm than before but shift at right rpm. I haven't put my foot into it yet, not gonna push my luck until I figure things out. Luckily I have 3 pcms so I can afford brick a couple lol. No security light so far and only weird thing I noticed so far was that the emergency brake light came on for a bit, other than that everything seems to be functioning properly with the OK pcm.
 


sugaryuk said:
I've got the instructions that came with my HPTuners sitting right in front of me-- it reads:

CAUTION To avoid damage to your interface, only power the laptop with a fully charged laptop battery. Do not plug the laptop into another power source. The HP product obtains power from both the laptop and the vehicle. This causes unique issues when there is a voltage offset between the two voltage sources that can cause catastrophic failure. Do NOT utilize a DC to DC converter to power the laptop as doing so may cause damage to the interface of the vehicle that is not covered under any warranty. Damage to the interface or the vehicle that is caused by a voltage offset is not covered under any warranty.

Didn't seem worth it to me to chance it so I got a new battery for the laptop.
Click to expand...

Same thing. It doesn't say anything about plugging it into your house. Just a car that can have power surges.
 
Another power source is a wall outlet, but hey it's up the end user if they want to do it that way. I'll continue to just use the laptop battery itself.
 
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Decided to use the 03 pcm with the OK tune on it and copy the gt tranny tune to it. Seems to have worked, tranny is shifting fine-- a little bit blah on the shifts so I might start looking for better tune to firm up the gt tranny. Motor definitely needs some fine tuning, no.1 has a misfire going on, still throwing a p0134 and dam slp's are leaking at the collector/crossover. But at least it starts and drives!
 
check fuse 21 marked ign.

rtv and band clamps for the cross over.

swap the coils around. same with the plug wire and plug to hunt the misfire down.
 


Scottydoggs said:
check fuse 21 marked ign.

rtv and band clamps for the cross over.

swap the coils around. same with the plug wire and plug to hunt the misfire down.
Click to expand...

Already have band clamps on so time for the red stuff, might have to reposition the rear header- seems to hitting the new Dorman swaybar I put in (or flip the bar). Tried swapping the plug, wire and coil already, might be the injector? Also thought it could be the ICM, the rad got pushed into it from the accident I had in the 99GTP-may up screwed something up. Fuse checked out ok, I'll go over the wiring this weekend to see if I missed something.
 
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