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6 speed auto

12535 Views 30 Replies 17 Participants Last post by  jeffnles1
I was reding the g6 wil get a 6 speed sutomatic tranny?
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yeah, but anyone can go in and edit Wiki to say whatever they want. it is great for a starting point for real research, and while the information MAY be accurate, it can't be guaranteed.
Blackrider said:
I think we're getting a bit off topic here.
so you're still wondering if the G6 will get a 6 speed sutomatic tranny? i'm still on the fence about whether or not the sutomatic will ever make production, but if it does i feel confident that the G6 is a very likely candidate for it.
I think it's gonna be one of the first GM cars to get the 5 or 6 speed automatic treatment. It's one of the better selling GM cars, and when people think G6 they think something sporty. While I'm sure the baseline G6's will always stay with the 4-speed I think it's very likely the GT and GTP's will get the better transmissions.

bristol16 said:
so you're still wondering if the G6 will get a 6 speed sutomatic tranny? i'm still on the fence about whether or not the sutomatic will ever make production, but if it does i feel confident that the G6 is a very likely candidate for it.

wikipedia is not exactly the most reputable source. Ask yourself "where do they get their info?" and you might wonder why you are posting something about cars build in 2009 and 2010.

I don't even think that Mr. Wagoner knows what will be produced then.

Look at Porsche. There was one time that the CEO thought that the 911 and 99X platform would go away to make room for the 924 and 933. OOPS!

The article you quoted states that the Epsilon 2 will be "adaptable for front and all-wheel drive applications." What about the Cadi CTS? It's rear wheel already and Pontiac wants to go rear-wheel exclusive over the next 5 years.

Be patient - who knows what the future will bring. Just keep buying North America in hopes that one day we might find a winner.
mphred said:
The boatload of torque the 3.9L has is available at a very low 2300-2500 rpm from what I've read.
I seriously doubt that the DOHC's torque peak is below 3000 rpm (DOHC's are inherently revvier) and the difference in quickness will probably be negligible between the '06 and '07 GTPs.
Hmm, just joined here from the GA side 'cause I was bored, LOL.

About the LY7 (3.6L DOHC)... As much as the pushrod ppl (I'm one of them myself, lol) might like the LZ8/LZ9 (3.9L "3900" OHV), the LY7 is quite a nice engine. I'm really glad/excited GM is offering the LY7 in the G6 and Aura for 2007.

The LY7 reaches it's torque peak at just 3200rpm (251lb*ft). It does kinda spike downwards slightly to 4000rpm but it slowly goes up again as it goes towards 5000rpm. The torque peak is not below 3000rpm but it's actually at a lower RPM than the 3900's torque peak.

The LZ8/LZ9 on the other hand reaches it's torque peak at a [relatively] lofty 4600rpm (240lb*ft). That's 11 less lb*ft and 1400rpm later.

Now you might think the 3900 has more low-end torque in general though, right? Not so. :p The LY7 has very similar torque levels as the LZ9. In fact, right from the lowest RPM where torque figures appear on the graphs (looks around 1200 RPM to me), the LY7 is already making just over 200lb*ft of torque. The LZ9 on the other hand is at perhaps only 180lb*ft at that point.

At 1500rpm, the LY7 is making perhaps 210lb*ft while the LZ9 is just breaking into the 200lb*ft level. At 2000rpm they are both making what looks like a similar amount of torque (~220lb*ft). The LY7 however continues more rapidly to it's torque peak (gets there at a lower RPM as discussed above) and it has more torque overall.

The LY7 does take longer to get to it's power peak (252hp @ 6300rpm v. 240hp @ 6000rpm) but looks like it has slightly more power at 6000rpm than the LX9 does anyway.

The only thing the LZ9 appears to enjoy over the LY7 is that the torque curve looks smoother. Oh, and of course, the fact that the LZ9 can be mated to a manual transmission whereas the LY7 is automatic only.

Anyway the proof, if you need it is in these graphs below, both SAE J1349 Certified ;) :
http://media.gm.com/us/powertrain/en/product_services/2007/HPT Library/HFV6/2007_36L_LY7_G6.pdf

3.9L "3900" LZ9
http://media.gm.com/us/powertrain/en/product_services/2007/HPT Library/HVV6/2007_39L_LZ9_G6.pdf

[Note there is a difference in the torque scale on the side, so be careful when comparing them, you have to take certain RPM points and compare the torque levels, like I did above.]

I'd agree with you that performance of the cars will be quite similar and probably not worth "worrying" about if you have an 06; but make no mistake the LY7 is no slouch. Compared to the 3900 with 300cc more displacement, it's breaking the no-replacement-for-displacement rule if you ask me ;)
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Yeah, you're right about an OHC being a more efficient package than an OHV. Wonder what Ferrari could wring out of 3.9L OHV or 3.6L OHC. I guess my personal disappointment with the 3.6L is the fact that that is a huge (relative) amount of displacement and losing only 0.3L in a transition to OHC design it "could have been a contender"- translated: should be light years ahead of the 3.9L numbers-wise, and yet it is awful close to the power output of the older design. I'm sure GM plans to get moe power out of it down the road, though.
Nice post Mantagreen97! :)

I do dispute the torque curve a little bit on the 3900 though. I happen to have my own evidence of it. :D

Now, you'll notice that the torque peak is just around 3250RPM, but 95% of peak torque is available just above 2500RPM even. I'm sure it's even available sooner, but my Dyno sheet here only shows from 2600+. According to GM when I bought the car, 90% of peak torque is available from 1800RPM all the way to redline.

You'll of course notice that my numbers are lower, as this is WHP, rather than crank HP.

Overall, I'd say that BOTH engines are almost equal in terms of what they put out, with the nod going to the 3.6 (LY7) for having slightly more peak power. The LZ9 does have a smoother torque curve though.

edit: You'll want to look at my second run more than the first. My first run finished too soon due to the 115MPH limit on the car, so 4th gear topped out at like 5100RPM. Second run was done in third.
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Did the 3900 change from 2006 to 2007? I thought the 3900 torque peak was at 2,800 RPM:


But the Pontiac website now says 4,600 RPM.
Everything I've read says 2800 for the 2006. I've not dyno'ed mine, but my ass-meter (never get tired of saying that) confirms this :)
I have an '07 with the 3.9 ('vert) and my "ass-meter" (like saying that too) says it pulls strong from about 1500 all the way to redline it pulls strong. This is one of the smoothes engine/trans combos I've ever driven. It has the 4spd auto mated to the 3.9. From behind the wheel, my meter does not feel any flat spots in the torque curve at all.

I don't know where peak torque is at, but I'd have to say the strongest pulling is from about 2500 up to about 5000.

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