I found a link to an interesting article over at GM Inside News discussing the Displacement on Demand technology being implemented by GM on the Gen IV V8 engines beginning with the 5300 offered in the Trailblazer, Envoy EXTs and the SUV as well as some discussion on the upcoming 3900 series engine to debut in the G6. It's an interresting read, so check it out... the performance implications look very promising.

Link to the article.

 

so what happens when you want to put in a hotter cam? do you have to get new pushrods and reprogram the computer?

 

The article says the pushrods are the same length for both types of cylinders. Maybe you could even just put normal lifters in the cylinders that are supposed to have the DOD ones as a means of bypassing the system. But I'll bet it won't be long before tuners or programmers (e.g. LS1Edit) will be able to turn off DOD permanently if you want to.

 

It would only be a matter of swapping out lifters and disabling (unplugging) the solenoid that controls oil flow to the DOD lifters. Probably would set an SES light but that's what LS2 Edit would be for, LOL.