I've been looking over the benefits of my pending twin turbo 3500 from the G6 which I will not bore you with, and noted in addition to the weight savings of going with the aluminum heads which weigh probably less than half as much as the cast iron, the starter is also pretty small. It feels about half as heavy as the stock starter which in this case is on the left for those who don't see the difference is from a 3.4L hence the bolt pattern, it's not much different than the fiero's starter in terms of weight. I believe the A/C compressor is lighter also it feels like it and from taking inventory of the different parts wouldn't doubt if there is roughly a 50 lb difference between the two engines 3.5 & 2.8 in full dress, they really cut some weight with the harmonic balancer also which is lighter than those before it. The starter isn't cheap new or used unless you are fortunate enough to find one at a good price.
On an odd note, I have two 3500 engines one from an 04 Malibu and one from an 05 G6, since sometimes GM does favorable things they don't tell us about like some of the camaros and firebirds getting the newer LS6 block when it was just going into the corvette, I'm curious about the timing cover differences, the malibu engine timing cover is plane with a slight brown tint in color, the G6 engine timing cover is the clearer aluminum color that you would expect on a new aluminum part and it has a "ROUSH" patch on it which the salvager got suspicious of when he saw it after it was pulled from the shelf as if he might need to go back and make sure he wasn't under charging me. I only know the name through mustang performance and have no idea of what hand they have in the manufacture of this particular engine. I'll see what I can find out when it goes on the dyno at 10-12 psi with the cam regrind in about 2 months hopefully less.
