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Pontiac G6



  • batistabatista Posts: 159
    I now know why the 3800 V6 never got a horsepower increase after the year 1998.
    It would suck gas like a V8. You mean to tell me that to get 40 more horsepower out of that engine (same engine as the 3.5L but increased to 3.9L) it would result in 18 city/24 highway. This is the same kind of fuel economy that a 345HP 5.7L V8 hemi engine attains. You have to be stupid to waste your money on that optional engine especially considering how expensive gas is now. :P
  • venus537venus537 Posts: 1,443
    doesn't compare favorbably to the 3.5L engines from honda, toyota and nissan either. of course, only nissan offers this engine in a comparable sedan.

    was it really cheaper to develop/design the 3.9L then to just simply provide the already available 3.6L OHC? i guess GM considers that engine too high class for the targeted audience of the G6.
  • 14871487 Posts: 2,407
    The GTP gets that mileage because of its aggressive gearing and axle ratio. Obviously they have tuned this automatic for acceleration at the expense of fuel economy. IN future years, maybe 2006, the car willget DOD and a 6 speed auto so I would expect those numbers to improve by 2-3mpg. I do not understand why they tuned the car to get such poor mileage but I bet it was done to increase the performance gap between the 3.5 and the 3.9. I remember C&D saying the preproduction GTP didn't feel that much faster than the GT. The high axle ration may change that and get the GTP some decent 0-60 times.
  • 14871487 Posts: 2,407
    It's not just about designing a new engine, its about material and assembly costs. The 3.9 is probably siginificantly cheaper to build than the 3.6 as well as other OHC engines. On top of that it provides better low end torque than the version of the 3.6 found in the Lacrosse and Rendevous. The lacrosse CXS isnt much faster thann 3800 equipped W cars because of its meager torque figures and I would be willing to bet the GTP will be considerably faster. On top of all that it revs to 6400 rpm which is higher than some DOHC V6s on the market.
  • anonymouspostsanonymousposts Posts: 4,202
    But the 3.9l doesn't put out THAT much power and the MPG is pretty bad for a modern mid-size sedan. If they had done better with the engine it would've been at least worth a test drive once the GTP came out. As it is, their lack of a modern engine choice has made me cross even a test-drive off of my to-do list once my lease ends.
  • m1miatam1miata Posts: 4,556
    Here ya go, all the power and decent gas mileage... sidenav..6.Chevrolet*
    Yes, I too would not get the 3.9 engine, as the performance to gas mileage ratio is not good. Actually, I think the old 3.8 engine is just fine and you can get 30MPG or better with that engine in just about any car. Whatever the base engine is in the G6 is just fine. It is not a dragster car. If one needs a street racer, go with a pony car, like Camaro SS. The G6 can go zero to a speeding ticket just fine. It is not going to be good enough for the track, so I assume people want the extra power to race on the streets, which is dangerous and illegal, all in one. The car could lose a little fat, but 220# torque is not all that bad. It will be a quick car, though not fast. It could diet a couple hundred pounds, or so. I sat in one of these G6 cars, and could not see any hood out front. Always think I am driving a video game, at some point. Not sure I want electric assist steering. I see they have given up on the 5 sp. on the floor. Guess people are more shiftless these days ;)
  • anonymouspostsanonymousposts Posts: 4,202
    because I want a manual transmission. Too bad I have to get an old-tech engine to be able to shift my own gears. I dont' want a street racer but I do want a sporty sedan with a manual transmission.
  • m1miatam1miata Posts: 4,556
    The GTP does not appear to be a good choice to me. Yes, you should be able to get a stick on all models. They don't seem to sell many sticks here in the USA, so it is all a matter of numbers. In the sporty sedan class, let's see, how about Mazda6 or the Altima? Maybe the Volvo S40? I imagine they are being discounted these days. Come to think of it, I can not think of many options for those wanting 5 on the floor, good gas mileage, sporty handling, and four doors. If the GTP gets 24 MPG on the freeway, for get it. Between the gas mileage, probably low resale value, and not all that high tech to the cars suspension and engine, I would pass on it. As for a 6 speed in the GTP, I would have to try it out first. Some can be a learning experience and a problem to slot through. Try before buy. As the cars get upwards to the $28K level, you can also consider a BMW or Mercedes on sale. And they are RWD. Sporty FWD cars, I would expect to pay under $21K for, on down to around the $18K level, like Mazda6. Most new cars can be had for $2k or more off sticker these days. Wonder if GM will stick a 5 sp. on the G6 some day?
  • venus537venus537 Posts: 1,443
    not so fast....

    the 3.6L provides more muscle at all speeds in comparison to the 3.8L. it provides more torque down low (230 @3200 vs. 230 @ 4000) and unlike the agriculture 3.8L, it maintains more torque at higher RPM. sure don't know what's so meager about those torque figures in comparison to the 3.8L. and the 3.6L is more than a little faster than the 3.8L.

    i'll take that bet about the 3.9L being considerably faster that the 3.6L. we'll have to see.

    the 3.9L has only 11 ft-lb more peak torque (at 2800 RPM, WOW, a whole 400 RPM lower) than the 3.6L. i have a strong hunch more of that torque is maintained throughout the RPM range with the 3.6L.
  • dan165dan165 Posts: 653
    I'll bet in real world highway driving, the 3.9L will get closer to 26-27.

    I can't see how it would only get 24, especially with a 6 speed. Doesn't a Vette get 27?
  • gunitgunit Posts: 469
    batista writes.........I now know why the 3800 V6 never got a horsepower increase after the year 1998. It would suck gas like a V8. You mean to tell me that to get 40 more horsepower out of that engine (same engine as the 3.5L but increased to 3.9L) it would result in 18 city/24 highway. ......

    The 3800 V6 in the Grand Prix GTP got a horsepower increase in 2004, from 240hp to 260hp! And Gas mileage remained the same at 18 city/28 highway.
  • gunitgunit Posts: 469
    venua537 writes.....The altima V6 does not require premium fuel......

    Nissan recommends premium-grade fuel for the VQ series V6s for Maximum performance. Same on my Infiniti with the same VQ series V6 engine. However you can use regular 87, you will just lose a slight amount of power.
  • gunitgunit Posts: 469
    G6 GTP 24 highway is pretty POOR when you consider the Competition's 240+ Hp V6, Altima, Maxima, accord all get 28 to 30 highway!!

    Even the 400 horsepower 6.0 Liter Six spd GTO gets 25 highway and thats a V8 and weighs 350 lbs more then G6, LOL! GM dropped the ball on this one. Axle ratio is very agressive in GTO too, 3.42
  • vanman1vanman1 Posts: 1,397
    Has anyone seen mileage numbers anywhere other than the Pontiac G6 site?

    I am still wondering if it's an error. Just seems to low to be true.
  • Hopefully that mileage estimate is for the automatic GTP. The 6 speed manual HAS to get better highway mileage then that. Both of my V8 powered 6spd Pontiacs (02 Formula & 04 GTO) with performance axles(3.42 & 3.46) get over 27 MPH highway in heavier cars.
  • e2helpere2helper Posts: 1,002
    You are right on the money vanman. The Pontiac web site is incorrect for highway. The correct number, I am told is 26 for auto (and it is a few higher for the manual trans). Thx for you inputs I have passed it along ;)
  • vanman1vanman1 Posts: 1,397
    Who told you?
  • alpha01alpha01 Posts: 4,747
    "The lacrosse CXS isnt much faster thann 3800 equipped W cars because of its meager torque figures and I would be willing to bet the GTP will be considerably faster."

    Are you sure about that? Everything I've read says the CXS LaCrosse feels and is significantly quicker than the 3800 CXL and CX LaCrosse. Can you cite some numbers? GMs 3.6L is a phenomenal engine.

  • batistabatista Posts: 159
    I was referring to the natural aspirated 3800 V6 when I mentioned that it never got a horsepower increase. Also, the 3800 SC did get a 20hp increase but it didn't result in better acceleration times. It was maybe 0.1 sec faster to 60mph than the Series II.
  • e2helpere2helper Posts: 1,002
    I can't say ;)

    However if I get any feedback about a correction planned for Pontiac web site I will post back.
  • vanman1vanman1 Posts: 1,397
    Looking forward to better news on that or the 3.9L will be out for me.
  • anonymouspostsanonymousposts Posts: 4,202
    "I can not think of many options for those wanting 5 on the floor, good gas mileage, sporty handling, and four doors."

    I found all of the above. That's why it will be hard to replace it. The G6 would be an option but I want the stick with a somewhat fuel-efficient, modern engine. I really don't like the 6, looks kinda dated to me. The Altima's interior is unattractive to me.
  • hammen2hammen2 Posts: 1,313
    Hey e2helper, maybe you can provide feedback to the powers-that-be that using the GTO exhaust sound to advertise the G6 on TV commercials is misleading and probably not a good idea? I realize that this may be an agency thing vs. a Pontiac thing, but still, the expectation is the G6 sounds like that, and the one my wife test-drove sure didn't sound anything like my GTO :-)

  • 14871487 Posts: 2,407
    I like the 3.6 so I dont why people are trying to convince me that its a good engine. I am just saying that in real world performance the 3.9 is going to be just as good, if not better for the G6. The 3.9 has VVT, more torque and makes peak torque at a lower rpm. On top of that it's redline is only about 100-200rpm lower than the DOHC 3.6. I cant see how anyone can discount a car based on the number of valves on the engine. Most people dont know the difference and I do not want to pay $29K for a lacrosse CXS that has a DOHC engine that offers little real benefit over a $26K G6 GTP with 3.9. The bottom line is the Lacrosse's engine needs a boost, it should have the same numbers as the CTS. I wonder if you people would prefer if the G6 had the CTS' 2.8L V6 with 210hp. I'm many of you would rather have that than a 240hp OHV engine. I agree that 24mpg on the highway isnt acceptable but we have yet to prove that is the fault of the engine.

    The fastest I have seen the Lacrosse CXS timed on 0-60 is 7.7secs which is about the same as the last generattion 3800 equipped W cars. The Lacrosse is about 100 pounds heavier due to sound deadening but that shouldnt be enough to slow it down that much. By comparison the grand prix GTP with 240hp was typically timed between 6.6-6.8 secs to 60. I definitely expected the lacrosse with 3.6 to be closer to 7 secs flat.
  • venus537venus537 Posts: 1,443
    "The 3.9 has VVT, more torque and makes peak torque at a lower rpm."

    the difference in low end and peak torque is small but the torque maintained at higher RPM with the 3.6 is not. we'll have to see how the 3.9 actually performs.
  • rwisemrwisem Posts: 96
    Consumer Guide's 2005 auto buying guide lists the CXS's 0-60 time as 7.1
  • dan165dan165 Posts: 653
    7.1 seems way low. I doubt it's that fast but..

    3.9L will likely be a little quicker off the line I think. OHV engines usually are.
  • m1miatam1miata Posts: 4,556
    Kevorkian buying into GM? Ooops, sorry that's Kerkirian ;)

    As for engine choices, the GM V6 of any flavor gets the job done. Most get good gas mileage. If they want to get something smoother and above and beyond the domestic
    competition, why not go with an inline six and rear wheel drive? It is not that some of
    the cars are not OK, it is that there are so many other choices in the price range. They
    are head to head with Japan and they should be doing something different, like some
    cars to get into the class of BMW only cheaper. The Datsun 510 was a huge success
    as a cheaper BMW. Just a thought. Or just let Kevorkian do his thing. The G6 may prove to be a good car. Time will tell. If it is a good car, it will be an outstanding used
    car value. I think many will wait.

  • 62vetteefp62vetteefp Posts: 6,048
    Why do you doubt Consumer Reports? 3.6 has excellent torque band for OHV engine. Almost flat the entire curve.
  • vanman1vanman1 Posts: 1,397
    7.1 seconds does seem fast. I would guess more like 7.5 to 7.7. Could be a typo.

    Nice engine though regardless.
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