GM's 3.5L vs. 3.9L
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From: Central Florida

OK, so I was scoping out the 2007 G6 convertible with retractable hardtop, just for kicks and reading the specs. Here are the basic specs:
So, for those of you who really know these things, why does the 3.9L only put out 10HP more than the 3.5L?
Sure it also puts out 19 more lb-ft torque, but it still makes me wonder.
What other reasons would someone pay that much extra for the 3.9L with those numbers? What am I missing?
Note that the 3.9 also gets much poorer gas mileage (which BTW, varies by 2 mpg, depending on where in the G6 site you are).
Engine & Power 3.5L V6 with 217 hp and 217 lb-ft of torque
OR
3.9L V6 SFI with 227 hp and 235 lb-ft of torque
Transmission 4-speed automatic, electronically controlled with overdrive (manual shift mode standard)
MPG mileage estimates**
3.5L engine:
20/28 (city/highway mpg)
3.9L engine:
17/24 (city/highway mpg)
Standard Capacities Fuel tank: 16 gallons (approx.)
Seating: 4
OR
3.9L V6 SFI with 227 hp and 235 lb-ft of torque
Transmission 4-speed automatic, electronically controlled with overdrive (manual shift mode standard)
MPG mileage estimates**
3.5L engine:
20/28 (city/highway mpg)
3.9L engine:
17/24 (city/highway mpg)
Standard Capacities Fuel tank: 16 gallons (approx.)
Seating: 4
Sure it also puts out 19 more lb-ft torque, but it still makes me wonder.
What other reasons would someone pay that much extra for the 3.9L with those numbers? What am I missing?
Note that the 3.9 also gets much poorer gas mileage (which BTW, varies by 2 mpg, depending on where in the G6 site you are).
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Joined: Jan 2003
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From: Bonney Lake/Ellensburg, Washington- WCBF '04, '05, '06, '07 Survivor-

I know the 3.9L use to be rated at 240hp, but I BELIVE, not positive though, they went DOD (Displacment on Demand) for 2007 for better mpg.
all i know....
all i know....
Thread Starter
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From: Central Florida

Originally Posted by Shadow
Originally Posted by lash
Originally Posted by Shadow
SAE reduction
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True Car Nut
Joined: Oct 2005
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From: Central Florida

Lol! I am well aware of what SAE means, as I was a member for 10 years and used to attend the SAE dinners at the Detroit Auto Show every year. I just wasn't aware of a new test method for HP ratings.
I have heard of a new MPG test and reporting method, intended to rid advertising of some inflated claims.
Anyway, back to my original questions:
I have heard of a new MPG test and reporting method, intended to rid advertising of some inflated claims.
Anyway, back to my original questions:
So, for those of you who really know these things, why does the 3.9L only put out 10HP more than the 3.5L?
Sure it also puts out 19 more lb-ft torque, but it still makes me wonder.
What other reasons would someone pay that much extra for the 3.9L with those numbers? What am I missing?
Note that the 3.9 also gets much poorer gas mileage (which BTW, varies by 2 mpg, depending on where in the G6 site you are).
Sure it also puts out 19 more lb-ft torque, but it still makes me wonder.
What other reasons would someone pay that much extra for the 3.9L with those numbers? What am I missing?
Note that the 3.9 also gets much poorer gas mileage (which BTW, varies by 2 mpg, depending on where in the G6 site you are).


