Current state E40 running an LS2 - Future state CTS-V LSA

[norcalvp]

This will be rather long?

I have a 70 Chevrolet that I swapped a 2006 Pontiac GTO LS2 T56 into. I used the stock E40, wiring, BCM, steering column, brakes, etc. the car runs and drives, the stock GTO key fob unlocks the car, clears the security/VATS, and everything works. The stock GTO gas pedal communicates to the E40, not sure if it goes through the BCM. Cruise control functions, and I believe this is a function of the BCM brought the PIM.

About 3 months ago, I bought a 2012 CTS-V (wrecked) with an auto transmission. I also picked up a ZL1 TR6060 as I want to keep the 6 speed transmission.

I?ve, also got a 2012 CTS-V manual wagon so I?m hoping that if I need to get the manual transmission tune, I have it in-house.

So, here is what I want, and I?m hoping to get a little guidance. I want to keep the GTO BCM, KEY, and Cruise control stalks. I really want to keep Cruise control, and if possible, I?d like to keep the GTO security and key. I?d also like to have all of the stock CTS-V measurements that come stock on the E67, I?d also like to use the CTS-V FPCM, Fuel pump bucket, and the stock LSA wiring.

Is it possible to graft the CTS-V E67 to communicate with the GTO BCM? To have the GTO BCM to clear the security/VATS? Would I be better off using the GTO E40 to control the LSA? I?m at the point of parting out the CTS-V where if I go further, it won?t be operable. Is there any prep work that I should do before I disconnect everything?

Thanks,

Steve

[blindsquirrel]

Nope, the GTO, being an Opel platform that Australia took and adapted and then GM NAO took and adapted again for the U.S., the network stuff is all weird and pretty much unlike anything GM did as U.S.-native designs. The CTS is its own version of Opel-derived weirdness but at least uses standard GM comms network.

You also can't use the E40 to run the 2012 engine, unless you want to deal with the hassle and reliability issues (allegedly?) of using the Lingenfelter 24x-58x converter box - OR - pull the engine apart and change the crank reluctor, but it sucks to do that to a complete, good-running engine.

Swapping the LSA top end onto the LS2 shortblock is probably the second-least disruptive option to a setup where everything works nicely together. Least disruptive would be to put all the new parts into a different donor.

[norcalvp]

So using the TRG-002, that?ll convert the 58x/4 signals to 24x/1. That solves two problems. What about the different style MAF? And the rest of the sensors that the LSA uses that the stock GTO never did? I understand the E40 is a little challenging to modify compared to the E67. The LSA also has larger injectors, flex fuel, and a PWM controlled fuel system. Any chance the E40 can accommodate any of that stuff?

[blindsquirrel]

Injectors, yes. The rest of the fuel system stuff, no. The E40 is really nothing but a Gen3 PCM but with the TAC built-in. E67 has all that new-fangled VVE garbage. MAF still outputs a frequency like any other GM MAF, it would need to be tuned same as any other GM MAF, same as it would have to be tuned even if you used the stock E67 (intake plumbing changes and whatnot).

E40 is limited to 256kPa MAP linear max, and no negative offset. Can't use the stock LSA MAP. There is a Holley Sniper '2.5 bar' MAP in the LSA/LS3 bolt-down config, but Holley does not know what the linear/offset specs are on that part.

I have the ability and parts on hand to build another one of these, if you decide to go that route and can't find another solution... https://forum.hptuners.com/showthread.php?91757

[blindsquirrel]

Whether you use the E67 or keep the E40, I would change to a return style 1:1 referenced fuel pressure regulator. With all the other work needed to do this that would be approximately zero trouble. With a returnless system and no variable speed pump, boost reduces injector flow and limits your HP potential for a given size injector. Referenced regulator keeps fuel pressure at the same level above manifold pressure so that even at 14lbs boost the injectors still flow the full 52lbs.

With a returnless system, boost above ambient effectively reduces the fuel pressure by the boost level so your 52lb@58psi injectors turn into 45lb@44psi injectors.