l76+6l80/280z swap

[wasey]

Just curious if anybody has contemplated this setup. Any problems with the DOD and it's settings(wiring and so on) and most importantly the transmission mounting(size, shifter, etc.)?? I am most likely going to use the JCI kit. Also just fyi this is the engine/tranny from the G8 GT.

 

Thanks in advance

[BRAAP]

I have been looking more and more closely at the GM Gen III/IV engines lately. My guess is if the DOD is present and you are using the OEM computer, there must be a way to utilize it. Otherwise, I would assume most of its components could be removed, (the oil pressure fed actuators are in the valley,) for a V-8 Z car. The fact that the L76 has VVT, (Variable Valve Timing by way of phasing the “in-block” cam), that is very intriguing.

 

 

For those who don’t know what GM’s DOD is, it is the acronym for Displacement On Demand. The official GM acronym is AFM which stands for Active Fuel Management or AFM. I prefer the DOD acronym myself.

 

 

Here are the current GM RPO’s with AFM, Comp ratio, and block material.

 

5.3L;

LH6 AFM (most versions) 9.9:1 Alum.

LY5 AFM 9.9:1 Iron

LMG AFM (Flex Fuel) 9.9:1 Iron

LC9 AFM (Flex Fuel) 9.9:1 Alum

LS4 AFM (FWD cars) 10:1 Alum (Buick Lacrosse, Pontiac Grand Prix GTP, Chev Impala SS, Monte Carlo SS)

 

6.0L;

LFA AFM (Hybrid w/VVT and LIVC) 10.8:1 Alum

L76 AFM 10.4:1 for car versions, (VVT in Truck versions w/9.6:1) Alum (Pontiac G8 GT) Alum

 

(LIVC is GM’s Late Intake Valve Closure)

 

These 2 RPO’s are VVT only, no AFM/DOD

6.0L;

LY6 VVT 9.6:1 Iron

 

6.2L;

L92 VVT 10.5:1 Alum

[wasey]

Thanks for the response. I was looking at the LS4 thinking that it is shorter would make it nice to have too, anybody have any inputs on it?

 

The ly6 might be a less expensive alternative to the l76 and still have that nice 6spd auto.

[BRAAP]

If it helps in choosing from what is available, here is the complete list of Gen III/IV engines...

 

Courtesy of "How To Rebuild GM LS-Series engines", written by Chris Werner

 

Courtesy of "How To Rebuild GM LS-Series engines", written by Chris Werner

 

And a VVT tid bit...

Courtesy of "How To Rebuild GM LS-Series engines", written by Chris Werner

[wasey]

So does anybody know if the 6 speed auto has any fitment issues??

[Cable]

Another run at the top....

[SUNNY Z]

I'm going to say yes. You will likely have fitment issues. the 6l80e is a massive transmission. Just my opinion though, I have been wrong before

[Filmjay]

I have a 6L80e. When I start digging into the car in a couple weeks, I'll try to remember and measure it for you guys.

[kj280z]

Does anyone know if the DOD is dependant on the 6 speed auto in any way? I have heard that both pcms receive input from each other. How hard would it be to us the L76 DOD motor with the T56 and preserve the DOD features for fuel economy?

[wasey]

I have a 6L80e. When I start digging into the car in a couple weeks, I'll try to remember and measure it for you guys.

 

Thanks, much appreciated.

[wasey]

Does anyone know if the DOD is dependant on the 6 speed auto in any way? I have heard that both pcms receive input from each other. How hard would it be to us the L76 DOD motor with the T56 and preserve the DOD features for fuel economy?

hmmm... good question too. I don't think so, not every V8 car with the "DOD" has the 6spd auto so it should be easily tunable I would think.

[Cable]

I have a 6L80e. When I start digging into the car in a couple weeks, I'll try to remember and measure it for you guys.

 

It should fit, especially after a few well placed hits with a dead-blow hammer.

 

Does anyone know if the DOD is dependant on the 6 speed auto in any way? I have heard that both pcms receive input from each other. How hard would it be to us the L76 DOD motor with the T56 and preserve the DOD features for fuel economy?

 

I believe the reason it isn't offered on the manual trans cars/trucks (among other reasons) is because in order for the DoD to work correctly there is some type of harmony that must take place with the auto trans to make it all work.

 

I hate to say this, but if you are looking for all-out fuel economy you are in the wrong hobby.

[SUNNY Z]

 

I hate to say this, but if you are looking for all-out fuel economy you are in the wrong hobby.

 

 

:icon46:LOL this is the truth. I think my camaro gets about 10 in town. 18 highway. not bad for a ~450 wheel horse, 3600lb ride though.

[kj280z]

I hate to say this, but if you are looking for all-out fuel economy you are in the wrong hobby.

 

Not true at all - without DOD - with proper tuning I have a few ls1 240Z friends getting well over 32 mpg AND can still run low 12's - with DOD I'd bet 36+ is possible. I don't know about you but, this would make my Z more of a candidate for a daily driver since I have a long commute, but I could still use it on weekends for all my racing activities (road coarse (DE), autoX and occasional drag) - makes it a very well rounded all around car.

 

Part of the reason for this post is to discuss DOD - which it's ONLY purpose is for fuel economy

[SUNNY Z]

This is yet another question I would post on LS1tech. There are far more LS gurus over there.