BrianPA

That's because it doesnt' rev that high.

sjsharks

Quatermile

It is not necessary that the numbers on both sides of the graph match, they are not measuring the same thing anyway. In some ways it is misleading. One side could go up to a million while the other goes to 10. As long as you know how to read it, and use it to compare the relative comparisons.

Bottom line is that your chart and the other ones say the same thing. The 997 can match the GT3 all the way up to the final lunge to redline where the GT3 dominates. I think we all knew this anyway.

Sanjeevan

Skip, thanks for the post, I knew 997S will be a great performer, but nice to see how great it is even compared to a GT3, WOW. Quartermile, you have a GREAT car, but your arguments are totally flawed, you are making it clearer with each post you have no clue what you are talking about.

Mikey

"you have no clue what you are talking about."

I rest my case ~ everyone on this board seems to be smarter than me.

BrianPA

I think what everyone is falling to consider is that these graphs are based upon quoted crank numbers. I haven't seen any dynos from 997 S yet. The 997S is rated at 355 hp but we have no idea what it really is. The GT3 is rated at 381 horsepower but it clearly has at least 20 more horsepower than that. The torque may be even more substantially under-rated on the GT3 because I have seen dynos in the 270 range and the GT3 is only rated at 284 ft lbs.

Until someone has a few 997 S dynos to compare to a GT3 dyno we can't draw any conclusions here about whether or not the 997S can match the GT3 in power the way these charts would lead us to believe.

Sanjeevan

Dang, you are smarter than I had given credit for, I thought you'll take my bait . You have some excellent pointers on dynos, but you choose to ignore everything else and come to some severe biased conclusions. When you say a 997 is a boxter, you loose all credibility (I know why you are saying it, but I hope you have the smarts to know why it is a non-sensical conclusion, they are very different cars), and c'mon man you have to recognize those hp. torque graphs straight out of the porsche manual. In conclusion 997 and GT3 are different cars, your's is still the better package for the track, and obviously 997 is a better all-around car. But, I think the point for starting this thread is to show how well porsche has done with it's 997s compared to EVEN the GT3.

Sanjeevan

Brian.P i didn't see your post, but I agree with you. (1/4mile has some great pointers on dynos as i had said), but he has to tone down his style

M758

Guys,
Skip just went an overlayed power & torque from both 997S and GT3. This an "intersting" exercise, but does not "prove" that much. The cars do have differenet weight and different feels too them. 997S and GT3 are not "equals". They are different cars. Lets face it even a GT3 is not about HP. If you want HP get a Turbo or GT2. GT3's are about balance and an uncompromising track willingness. The 997S is street car for the masses. A fine car to be sure, but it does not have same purity as a GT3.

As for which one is faster at the track. Hmm my guess is that it will be whoever is the better driver.

Sanjeevan

SkipSauls

Here's a link to the Excel spreadsheet I used for the graphs:

997Svs996GT3.xls

It has the original tables in kW and Nm, the converted table in HP and ft/lbs., and the lbs. per HP table. There is a corresponding graph for each, and you can change the graph type if you'd like to see the data differently.

As for dyno numbers, the only true way to tell is to measure the cars back-to-back on the same dyno under identical conditions. Anything else isn't valid as dyno figures are notoriously easy to manipulate. If you're hoping for a higher reading then the dyno operator can probably grant your wish.

I'm taking my GT3 Cup to the dyno on Wednesday to see how it does after 5 races this year. It was putting down 430 RWHP last Fall, and we're using the same dyno and hopefully similar enough conditions to make the comparison valid. The "butt dyno" says that it is doing well, and it has no problem with similar cars in terms of acceleration.

I'll be happy to pay for a dyno session for the 997 S if a GT3 owner in the area wants to do the same. We'll run them back to back, same conditions, and so on. All results will be published on rennlist. Any takers?

frayed

Agreed. Very different driving experiences, but I'm thinking these cars are close enough that laptimes will be largely driver dependent (though the 997 will be less demanding of driver skill)

For me, I'll take the newer, more refined chassis of the 997S, with sunroof delete and sport suspension (dumping PASM). I think it'll prove a wolf in sheeps clothing.

CKarras

How do you characterize the greater refinement of the 997S chasis? I would have thought the GT3 had a more adjustable suspension.

Does the sunroof add any significant weight?

Can't one turn PASM off?

SkipSauls

Chris, PASM can be put into "sport" instead of "normal", but there isn't any way to turn it off, and I'm not sure if that would do much. What you can turn off, at least in part, is PSM, but my understanding is that it still works during braking and is never completely disabled. I'd probably opt for PASM unless an aftermarket suspension is going to be used, and even then it remains to be seen how well these will work.

The sunroof in the 993 added some weight, including the extra metal frame in the roof, the motors, rails, water channels, and so on. I'd guess 10 lbs. of weight, maybe as much as 20 lbs., but it's not a huge difference. You may get some additional chassis stiffness without the sunroof, but modern cars are often designed for sunroofs, cab tops, etc. and that may not be the case.

The greater refinement is what Porshe itself claims versus the 996, including chassis stiffness, suspension mounting points, improved suspension geometry, and so on. It's to be expected that the car will have evolved using lessons learned from the previous models. Note that I'm not saying that a 997 S is going to have better handling than a 996 GT3, although I'm sure some will take it that way.

The great thing that should make everyone happy is that if the 997 S can come as close as it does to the 996 GT3, imagine how much better the 997 GT3 is going to be!

frayed

Sunroof: I find that I don't use mine much at all, and from the E46 M3 side of things, the weight difference turned out to be 30lbs or so, but that's 30lbs in the worst possible place. The thought is that the loss of a few pounds on the roof, the additional stiffness, cleaner looks, less potential rattling/NVH, more headroom for helmet wearing track day enthusiasts, make the sunroof delete option desirable among the track rat crowd. Also, sunroofs are optional and not standard in Europe, which might indicate that the car was not intentionally designed for one.

I'm still not completely sold on the idea, however, as it could impact resale. dunno. In addition, I just looked at the UK and DE specs vs. US. Only 6 lbs of difference, so the conventional thinking on sunroof inclusion may be misplaced.

Chassis: By chassis refinement I mean exactly what Skip said above. More use of aluminum to reduce unsprung weight, modified pick up points, wider track, and even wider positioning of the hub carriers (notice the big change in wheel offsets showing hub locations even further outboard), revised damping, presumably better camber control up front, better toe control out back, stiffer chassis, particularly in bending (moderate in torsion). From my experience, the refinement was so good, that the car did not feel obviously rear engined and gone is nose bobbing characteristics of past 911 and excessive dive/squat. . . all this w/o punishing the driver with ride harshness. The improvement in chassis development from the 996 to the 997 is what I'm giddy about, and why I want one.

PASM: I think that PASM will prove to be a capable setup, but not a replacement for properly matched damping and springs. Case in point: The Sports suspension option is not Active, and the 997 GT3 will not have PASM. Surely, Porsche would have put PASM in the GT3 if it proved better for track use. Also noteworthy, the sports suspension option makes use of a proper limited slip diff, just as the 996 GT3 does and the 997 GT3 will, rather than relying on electronics to put the power down (I think through differential braking, but not totally sure). I'd pick a proper diff over an open diff and electronics any day.

The Porsche track times bear this out. The PASM 997S in sport mode, runs an 8.02 with Walter at the wheel. In the PASM-neutered Sport Chassis car, Walter pulled a 7.59, and stated in the latest Excellence that the car still has another 3 seconds. To put this in perspective, this prospective 7.56 lap time is what the 996 TT does, and only two seconds off the pace of the compartively unforgiving 996 GT3. Good stuff.

I think the 997 GT3 will surely prove badass, eclipsing the 996 version, even if it does not have the GT1 derived block. Every generation of 911 has upped the performance bar by a noticable margin, and the 997 will not prove to be an exception.

Of course, all in my opinion.

RSA333

The next generation 997 GT3 street car will be 997S based, on the newer 3.8L engine (check engine numbers). It will be due in '06. It will be launched in the US.

The new 997 Turbo is going to be lanched in the '06 timeframe (see RennTeam discussion list).

I know these things, but I am a simple list member.

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92 RSA
93 911 Turbo S2
80 Sc