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Wonder how much more power and TQ is lost through an auto ? I mean compared to the manual tranny ? Also does the shifter area look alot different on the Auto ? I know there will be the selector slide. I just wonder if it looks as good as a manual on the interior.:)
 

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I've had a chance to look at both & yes it looks great. If my memory serves me correctly, its chrome plated as well.
 

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Generally the rule of thumb is you lose about 15% with a manual and about 20% with an auto. So to answer your question you lose about 5% more with an auto tranny than a manual. A manual always looks better with the interior :cool:
 

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the information I have see they are about equal in performance, you will just lose a small amount of gas mileage... maybe a couple tents slower in 0-60.. but not noticable in everyday driving...
 

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bluestang50 said:
Generally the rule of thumb is you lose about 15% with a manual and about 20% with an auto. So to answer your question you lose about 5% more with an auto tranny than a manual. A manual always looks better with the interior :cool:
On my Auto Trans, there is actually a soft black leather boot at the bottom of the shift so to a casual observer, the auto has a "manual look." Certainly a "sporty look."

I'm still just under the 500 mi breakin so I haven't really tested her but the car is very responsive from a dead stop; I'd say quick - not fast.

Otherwise the shift console is finished in chrome just like the manual.
 

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CJREDLINE said:
Wonder how much more power and TQ is lost through an auto ? I mean compared to the manual tranny ? Also does the shifter area look alot different on the Auto ? I know there will be the selector slide. I just wonder if it looks as good as a manual on the interior.:)
None. The GM engineers said 0-60 times are faster with the automatic then the manual. Here are a couple post that had discussions with the engineers from the Solstic forum.

Please see attached post:

First Post :

I spoke with the engineer at the Solstice Meet when looking at the Mean GXP on display. I asked him some questions in regards to the performance peramiters of the GXP. Specifically, concerning the difference between the automatic GXP and the 5-speed. I asked him if the 5-speed would be able to keep up with the automatic, and also what could we expect in regards to times to 60mph. He said that the GXP automatic on a good run could hit 5.2 and on a really good run 5.1. He said that the 5-speed could hit 5.4 or on some good runs 5.3, due to the loss in shifting the 5-speed. At the time I didn't know anything about this extra additional part or "piece" that would enhance performance that was announced by frankc on July 17th. It's possible that the engineer may have known about this performance enhancement. I don't know? This engineer was involved in the development on the engine. Thought this might be helpful to the future GXP owners. This was the same gentleman that addressed the group and answered questions at the Banquet.


__________________


#1 On my local GXP list at MSRP

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Second post :

You had a very interesting conversation with the enginner. Wish I could
have been there but I was at Salt Lake ALMS race with the C6R's where
it was 107 deg-hot!
BUT, I had come to a conclustion to buy the automatic based on the fact
that modern automatics can shift faster than you can and you can get
immediate quick acceleration with the quick downshift of an automatic.
The engineer that you talked to confirms my guess that the auto was
as fast and in this case faster than the stick.

But then I had a conversation with a GM powertrain engineer very
familar with the auto in the Solstice and was told in no uncertain terms
I should buy the stick, so I changed my order. But I did not get a chance
to have the engineer outline the complete details of the reasons to change.
I suspect as the previous post has noted that the characteristics of the
auto deaden the throttle response somewhat and that was the reason for
the suggestion I received. Where the auto shines is the modern ones, if
programmed with higher pressures etc, will shift faster than you can with
a stick. If you like drag racing over road race response, it appears the auto
may be better.
 

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During non aggressive driving, the auto goes into lockup, which eliminates any
advantage the manual may have enjoyed re MPG. The auto will shift at proper points for the best MPG and lock into the most optimal gear. The manual shifter is just guessing when it comes to the most efficient gear at a given speed.
For acceleration, most autos, for most people, will do better than the manual. Unless you're very good, the auto will shift faster and at more optimal speeds.
I've known very few people that were really good at shifting. I did see one at a dragstrip, and after he easily beat another guy, they switched cars and he beat him again with the other guy's car. People always spout about wanting "to be in control" of the car as a reason for buying a manual, but they fail to understand that an automatic will almost certainly control the car much better than they can.
 

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Auto will also be heavier as well. I would much rather shift for myself at what ever RPM I want. I respect GM's engineering but I want to be the one who decides when to shift and how hard, I don't need a committee decision that rules out on mileage vs. performance. I'm sure the Auto is a great tranny but it is not going to drive the car better then I can.

You all are also forgetting about driving with the turbo too. With an auto you can't pre load a turbo unless you power brake it, with a manual you just press in the clutch and rev match it as you like. The turbo has minimal turbo lag but I'll still need to get the turbo spinning when I drop down a gear or two and I don't want to wait for the turbo to catch up. Taking off from a stop you can launch at a higher RPM initially keeping it at full boost with a bit of clutch slip.

For the average middle-aged baby boomer the auto probably will be faster, for those of us with some drag racing experience and turbo experience, we'll make the manual faster. This is just a preprogrammed regular five-speed; it is not a BMW SMG, Audi DSG, Ferrari F1, etc.

Essentially, if you go around granny shifting all the time the auto will be faster. If you have some experience with a turbo motor and you know how to power shift a manual you'll be faster
 

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bradyb said:
Essentially, if you go around granny shifting all the time the auto will be faster. If you have some experience with a turbo motor and you know how to power shift a manual you'll be faster
Bradyb, might want to explain the difference in these two for some on here. Many may have heard the terms, or similar terms, but not know the difference.
 

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granny shifting = shifting normally (letting out of the gas when you shift)

power shifting = staying in the gas while shifting (this deffinnently isn't the best for the transmission)

speed shifting = shifting as fast as possible not worrying about letting the clutch out smooth but you still let out of the gas when shifting

If you can drive a manual good speed shifting is fine you don't really need to power shift. This is especially true considering the power of the sky and sky redline isn't high enough to the point were it will make much difference if you powershift. With a stock tranny and stock to mildly modded motor i would strongly recommend against power shifting. Power shifting will shorten the life of your driveline dramatically.

PS never rev the car high enough while shifting that you hit the rev limiter, it just makes the person driving look like a complete idiot (this is a common thing done by ricers).

Back to the auto vs manual tranny question. For drag racing an auto will be much better, but not a stock auto. If we took two stock redlines (one auto and one manual) and put drag radials on them and ran them in the 1/4 the manual would win with a good driver. This would be because you would be able to launch the car at a higher rpm with the manual vs the auto stock for stock which would give the manual a jump off the line. When you start getting into modded cars and trannys then yes an automatic by far is better. By modding the tranny i am reffering to shift kits and higher stall converters which would allow you to launch at a higher rpm and also the tranny would shift more aggresively with the shift kit.
 

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Granny shifting is letting the clutch out all the way while taking your foot off the gas untill you engage the next gear

Remember how GM said the C5 ZO6 could pull off a 3.9 0-60 while power shifting. Powershifting is hard on the driveline and you should not do it very often, but it is the fastest way to get the car moving.

I'm guessing that speed shifting will be more then enough to beat out the automatic. You can do a combination of the three as well. For example matching the RPMS to the next gear while not totally letting off the clutch when you shift.

The point I want to make is that the 5-Speed auto isn't really anything special or at least special enough to be faster then those drivers that know how to drive. It's not like you'll see a higher stall converter available or a shift kit soon.
 

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bradyb said:
It's not like you'll see a higher stall converter available or a shift kit soon.
Anybody got a schematic of the valve assembly in the Sky's Auto? Betcha you could do what the old hot rodders do and build a "shift kit" from Ace hardware for all of $5.00. LOL That's what's in my Grand Prix. Not hard and the fluid/filter will cost you more than the parts. :)
 

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yes a little clutch slip makes a much faster gear to power on a turbo car. if i am raceing i will slip the clutch just a bit while shifting to get the boost to come on and make it a smother shift also you will lose less rpm than a fast drop in to seccond. at least on the twin turbo stealth i drive. it has 225,000 miles on it.
 

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Robotech said:
Anybody got a schematic of the valve assembly in the Sky's Auto? Betcha you could do what the old hot rodders do and build a "shift kit" from Ace hardware for all of $5.00. LOL That's what's in my Grand Prix. Not hard and the fluid/filter will cost you more than the parts. :)

which part do you want? theres two valve bodies, a spacer plate and then the case passages... and unlike the 4t65e the 5l40e was built from the start to be full electronic controls. the tcm controls all the parameters concerning shift timing, shift pressure, line pressure etc.
 
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