Question for Dwight....tradeoffs

[regfootball]

Seeking to tap Dwight's knowledge here.....

In terms of engineering and manufacturing costs and tradeoffs, technology vs. technology.....I want to throw these scenarios out there and welcome others to throw out some scenarios of competing powertrain details for evaluation.....

Or also in terms of weight and design and performance.

On the Cruze for example. The 1.4t does not have DI. Yet it has turbo. In terms of providing the most power and fuel economy for the projected sell prices, was the turbo "in lieu" of DI? i.e. was the turbo and DI about the same cost but the turbo provided more power and FE for the same price?

Likewise,

A car with a V8 and rear drive only or one with similar dimension but a highly charged turbo 4 with a performance AWD system. Can the weights be kept similar (does the 4 cyl save any weight to give back to the AWD system) if so is there a performance advantage to the 4 / AWD setup vs a strictly RWD + v8 solution.

I am sure many questions like this could be brought up. Another that comes to mind is extra gears in the transmission, does it make up for the added complexity and cost.

[dwightlooi]

Seeking to tap Dwight's knowledge here.....

In terms of engineering and manufacturing costs and tradeoffs, technology vs. technology.....I want to throw these scenarios out there and welcome others to throw out some scenarios of competing powertrain details for evaluation.....

Or also in terms of weight and design and performance.

On the Cruze for example. The 1.4t does not have DI. Yet it has turbo. In terms of providing the most power and fuel economy for the projected sell prices, was the turbo "in lieu" of DI? i.e. was the turbo and DI about the same cost but the turbo provided more power and FE for the same price?

Likewise,

A car with a V8 and rear drive only or one with similar dimension but a highly charged turbo 4 with a performance AWD system. Can the weights be kept similar (does the 4 cyl save any weight to give back to the AWD system) if so is there a performance advantage to the 4 / AWD setup vs a strictly RWD + v8 solution.

I am sure many questions like this could be brought up. Another that comes to mind is extra gears in the transmission, does it make up for the added complexity and cost.

(1) A turbo and its intercooler is about $500 (assuming GM sources them at 1/3 what you would have paid on the aftermarket). A DI system is less than that for sure. A high compression DI 1.8 with part-time Atkinson (ala Civic's R18) would be similarly efficient as a low compression 1.4 turbo at a lower cost. The 1.4 turbo will however have more torque and a more accessible torque curve. A 1.4 turbo will also be more "special" from a differentiation standpoint.

(2) An 2.0 I4 with AWD is about the same weight as a 6.2 V8 with RWD. The center diff, front diff and half-shafts are roughly the weight difference between the V8 and I4. The Turbo-4 AWD will launch better. The V8 will have better power to weight ratio.