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Top Swap Tune on L36 PCM - HPT

Impala131

New member
Hey all,

I'm doing a top swap on my 2004 Impala LS (currently L36). I have a .hpt file from a 2004 Impala SS (L67) that I used to own. Can I simply flash the SS PCM file to the LS PCM and edit from there? Imagine that there might be some VIN issues, but I'm not sure.
 


if using dhp you can do that and change the vin.

hp you can do that, but the vin will be the old cars vin,

once tuning, id lower the wot timing by one degree. top swaps dont like as much timing as a l67 does.
 
if using dhp you can do that and change the vin.

hp you can do that, but the vin will be the old cars vin,

once tuning, id lower the wot timing by one degree. top swaps dont like as much timing as a l67 does.

Thanks Scotty. So to clarify, will the PCM retain the LS VIN, even when flashed with the SS .bin?

Going to knock the timing down 4 degrees to start, then add back in after WOT scans to verify safety. I'll see how high I can go. Gonna have a Gen V stock pulley on there. Also gotta MAF tune for the LQ4/N* combo and the other f-ery I like to do in my tunes.

Also going to have to do some transmission table editing. The SS had 2.93 fdr (course you already know this) and 17" factory wheels, versus the 3.05 and 16" I have now.
 
you'l end up having to use the vin# from the SS that you have registered with hp already. it should write, right on the LS pcm no problem.

you use the sc'ed timing, but lower it a bit up top from like 3600, to 6400, take one or maybe two with a gen five blower.

on my car thats bottom swapped, before the intercooler install, stock pulley gen 3 with ported heads and rockers, one degree less made it kr free.

and it pretty much felt as strong as a 3.4 l67 set up easy.
 
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