Two Engine Swap Questions (less tuning than converting, really)

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March 9th, 2011
Admiral Ballsy

Two Engine Swap Questions (less tuning than converting, really)

Supposing a fella had a 2011 Corvette, LS3/M6. And that fella acquired an LS7, or at least its equivalent (sleeved LS3 with LS7 pistons/cam/heads/intake/et al). Am I correct in assuming that all one would need to do from an ECM perspective to make it work is flash with a stock LS7 file?

Part two - further suppose that said fella had a 2010 Cad CTS sedan, DI 3.6/M6. The LS3 from the Corvette is an easy swap mechanically...but what about the ECM? Presuming again, is it as simple as swapping the SIDI controller for an LS3 controller? I don't know if the connectors and/or pinouts on the harnesses are compatible, but connectors can be changed. Since manual trans, no AT controller issues...CTS tach will want a different signal frequency...any other things I'm missing?

Thanks in advance!
March 9th, 2011
ScarabEpic22

For the first swap, just need to appropriately tune the ECM/TCM. No, do not simply flash in a LS7 file, that is not the proper way to adjust for an engine. Besides, the stock LS7 file needs a fair amount of work done to it anyway. Copy the injector data into the original ECM tune and maybe use the LS7 VVE and spark tables as a baseline then adjust it from there.

For the CTS swap, I think its going to be pretty involved. I dont know for sure, but its not as simple as swapping engines and then adjusting the ECM/TCM. You might be able to swap in the E38, but it probably would take a bunch of work. The new electronics are finicky, some random module like the ABS might not like trying to communicate with the E38.
March 10th, 2011
Admiral Ballsy

Quote:

Originally Posted by ScarabEpic22

Besides, the stock LS7 file needs a fair amount of work done to it anyway..

I don't understand this. There are thousands of stock Z06s running stock programs, are there not?

Quote:

Originally Posted by ScarabEpic22

The new electronics are finicky, some random module like the ABS might not like trying to communicate with the E38.

You may be correct. I was thinking that since the CTS-V uses the same or similar controller as the LS3, most of the systems should be compatible.
March 10th, 2011
ScarabEpic22

Quote:

Originally Posted by Admiral Ballsy

I don't understand this. There are thousands of stock Z06s running stock programs, are there not?

But, you said in the first post it is not an LS7...it is an LS3 bored/stroked to LS7 specs. Is the cam identical to an LS7 one? Are the heads identical to stock LS7 ones? If the built engine is not a true, crate/production LS7 then simply using a LS7 tune would be pointless and not correct for the engine.

Basically, unless its an LS3 block with every single LS7 part on it, then its going to be different than a stock LS7 and therefore need a different tune. It might run decently, or it might not run at all. Plus I dont know if the Z06 OS will play nicely with the regular Vette, maybe someone can tell you but if you can use the stock tune and modify it, that is ALWAYS your best bet. If you're already tuning it with EFILive, why not invest a little more time and make it better than GM ever did?

Quote:

Originally Posted by Admiral Ballsy

You may be correct. I was thinking that since the CTS-V uses the same or similar controller as the LS3, most of the systems should be compatible.

True, but you never know especially now with the electronics even more complex than the LS1 setups. Heck I can take an OS from a Vette and flash it into my TBSS, but it wont run. Even if I change everything to mirror the TBSS setup, the Vette OS is different enough that it wont run the engine. And if it does, the ETC wont work, the ECM wont communicate with the BCM/TCM, just causes lots of headaches.