Quote Originally Posted by vt_maverick View Post
Just learned something... the same AR-5 manual that we're swapping into my VX was also used on the Pontiac Solstice GXP. That car featured a dual-turbo 2.0 L I4 Ecotec engine that made 260 hp and 260 lb-ft torque while getting 19/28 MPG. The VX is heavier by almost a thousand pounds, but you'd drop a good chunk of that just by going from a V6 to an I4...

So since we know an AR-5 mates to an Ecotec engine is it conceivable that you could swap that engine instead? Discuss...
Very much so, just wiring the instrument cluster would be the biggest concern. Add'l info: there is also a 2.4 non turbo engine, and it would also appear that the aforementioned 2.0 is the same engine in the Cobalt SS and HHR SS, as per ebay auction 130586906920.

I, for one, in order to increase gas mileage would strongly consider a 2.0L w/a 5MT, especially since there are aftermarket parts to boost the power of the 2.0L.