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Old 10-15-2012, 12:37 AM
  #136  
Petevb
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Originally Posted by 911SLOW
How so?
Heavy? Yes.. Outdated by the l/100klm stds? Yes.
"Biggest weakness" of the GT cars? Well, that's probably the weakest argument ever made in all of the posts ever made in all the automotive internet forums around the world..
The original 911 chassis had racing pedigree. It won LeMans, in fact. Should we have kept it around for 50 years?

We've seen the reaction when Porsche forced a 30 lb sunroof on GT3 owners- they were up in arms! Yet when Porsche finally takes away a 100+ lb lead weight off the back bumper, the same people who complained about the sunroof now cry like their big brother stole their ice cream!

The GT3 RS motor has a fully dressed power to weight of about .85 hp per pound. Great for 2001. In 2004 Porsche released the CGT, power to weight of 1.28 hp per pound. WTF have they been doing with the 911 for the last 10 years??

BMW M3 GTS, 1.05 hp per pound, Chevy Z06 1.04 hp per pound, Ruf V8 1.26 hp per pound, etc, etc. With any modern motor the tail of the GT3, right where you need less weight, would weigh between 100 and 200 lbs less than it is now. Easy 15 seconds at the ring, unarguably dynamically a better car all around. Porsche could do it with their eyes closed- they have proven that. Porsche can't do it with the Metzger- bolting on one band-aid after another (water cooling jackets, cooling pumps and pipes, etc) does not a light motor make. Nothing says they have to make a new motor cheap and crappy- we know they can build modern motors when they try (CGT, Spider, 918, etc).

So the choice comes down to this- keep your Metzger, keep 150 extra pounds right where you don't want it, and keep getting your butt handed to you by GTRs, or join the current millenium. Porsche finally made the right call, and you guys are complaining!

Last edited by Petevb; 10-15-2012 at 10:26 AM.
Old 10-15-2012, 02:42 AM
  #137  
wanna911
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Good points there, I don't know about 15 seconds though. I never knew those weight/power ratios for motor's. What is your source for the weights? Is that engine hp or crank hp because that would have some affect as well with various drivetrain losses.
Old 10-15-2012, 07:09 AM
  #138  
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Originally Posted by wanna911
I never knew those weight/power ratios for motor's. What is your source for the weights?
As you might guess, I weighed a few motors before throwing one in the back.

I challenge you to find a factory listed weight for a GT-x motor- there is a reason Porsche doesn't publish it. Closest I can point you to in print is Ruf's claim that their V8 weight 88 lbs less than the 3.8L RS motor that it replaces, and the ruf weighs 438 lbs, making the GT3 RS 526 lbs total (in a package that makes 100 fewer hp that the Ruf motor it's being compared to).
RUF V8, 2

Any way you do the math the gap is huge, ie 550 hp / 438 lbs = 1.26 vs 450 hp / 526 lbs = .85

This is not surprising when you realize that Porsche did publish the weights of their motors, dressed, back in the 90s. The 964 motor was 525 lbs, and that's before Porsche took that base, enlarged it, and bolted on a cooling system, water jackets, 4 valve heads, variocam, filled it with water, etc.

BMW, CGT, Aventador (1.35 hp/lb, but probably not fully dressed), Ferrari and other weights are much easier to come by of course; the manufactures are proud rather than ashamed of them.

Last edited by Petevb; 10-15-2012 at 09:11 AM.
Old 10-15-2012, 09:08 AM
  #139  
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Originally Posted by Petevb
The original 911 chassis had racing pedigree. It won LeMans, in fact. Should we have kept it around for 50 years?

We've seen the reaction when Porsche forced a 30 lb sunroof on GT3 owners- they were up in arms! Yet when Porsche finally takes away a 100+ lb lead weight off the back bumper, the same people who complained about the sunroof now cry like their big brother stole their ice cream!

The GT3 RS motor has a fully dressed power to weight is about .85 hp per pound. Great for 2001. In 2004 Porsche released the CGT, dressed power to weight of 1.28 hp per pound. WTF have they been doing with the 911 for the last 10 years??

BMW M3, 1.05 hp per pound, Chevy Z06 1.04 hp per pound, Ruf V8 1.26 hp per pound, etc, etc. With any modern motor the tail of the GT3, right where you need less weight, would weigh between 125 and 200 lbs less than it does now. Easy 15 seconds at the ring, unarguably dynamically a better car all around. Porsche could do it with their eyes closed- they have proven that. Porsche can't do it with the Metzger- bolting on one band-aid after another (water cooling jackets, cooling pumps and pipes, etc) does not a light motor make. Nothing says they have to make a new motor cheap and crappy- we know they can build modern motors when they try (CGT, Spider, 918, etc).

So the choice comes down to this- keep your Metzger, keep 200 extra pounds right where you don't want it, and keep getting your butt handed to you by GTRs, or join the current millenium. Porsche finally made the right call, and you guys are complaining!
Originally Posted by Petevb
As you might guess, I weighed a few motors before throwing one in the back.

I challenge you to find a factory listed weight for a GT-x motor- there is a reason Porsche doesn't publish it. Closest I can point you to in print is Ruf's claim that their V8 weight 88 lbs less than the 3.8L RS motor that it replaces, and the ruf weighs 438 lbs, making the GT3 RS 526 lbs total (in a package that makes 100 fewer hp that the Ruf motor it's being compared to).
RUF V8, 2

I have both personally weighed motors and got data from others who have, and these results indicate the weight above is on the light side, but any way you do the math the gaps are huge, ie 550 hp / 438 lbs = 1.26 vs 450 hp / 526 lbs = .85

This is not surprising when you realize that Porsche did publish the weights of their motors, dressed, back in the 90s. The 964 motor was 525 lbs, and that's before Porsche took that base, enlarged it, and bolted on a cooling system, water jackets, 4 valve heads, variocam, filled it with water, etc.

BMW, CGT, Aventador (1.35 hp/lb, but probably not fully dressed), Ferrari and other weights are much easier to come by of course, because the manufactures are proud rather than ashamed of them.

Some very good points Petevb but the question is: "is the 9A1 the answer we've been looking for?" If it were built with the same concepts as the Mezger, I'm sure it wouldn't be of concern to most...

The Mezger isn't perfect, yes its heavy but it is proven, bullet proof and built in a way whereby it can be rebuilt to like new condition. The replacable cylinder liners provide a platform for having and engine with the same tolerances after the 10th rebuild as the original... This is what makes it sort after and great. This is also what makes it perfect for category racing in the various cup car series...

The 9a1 unit will be lighter and less complicated and possibly more efficient but how's it going to perform in terms of reliability and how close to factory spec will one be able to restore it when rebuilding? No removable cylinder liners means boring it out and upsizing pistons to suit. In a race car rebuild scenario it will deviate further and further from its original specs resulting in loss of power and compromised reliability?... The couple engine builders/mechanics that I know well and have discussed rebuilding with have both indicated that a rebuilt motor never lasts as long or performs as well as from factory after its been bored/ honed and redone... The factory tolerances just cant be duplicated no matter how good you are... And the M96 and M97 were suppose to be modern engines but we all know how the lasted... The fact is that Porsche's motivation is as much $$ as weight and performance. A mezger costs twice as much as 9a1 as a crate motor yet we won't see a price reduction with the new GT cars... Instead it is expected that we'll see a 5% or so price increase... Hmmmm, gee, wonder why?

If they'd applied the philosophies of the Mezger such as a modular, rebuildable block, true dry sump, etc, etc whilst lightening the new block through incorporated cooling etc (ie Mezger of the 21st century), I'd be very excited... To me it seems however that they have taken the disposable, limited life format of other manufacturers and thats a let down... A lighter engine is awesome but its also gotta last, no?

And as for the Carrera gt and 918, no use comparing the engines in those as they are from a car 5 times the cost.... Ferrari and Lambo, so what? They have great power to weight ratios but can they go to the track week after week and slam out times for 300-400 miles per day? The pro drivers I've spoken to and train with say no and they are blown away each track day when I drive 200 miles to/from the track and slam out a good 3-400 miles on track at pace without it missing a beat... Thats what the Mezger rings to the party IMO... Never been the fastest, but combined with a great chassis, its been the most consistent and reliable...

Last edited by 911rox; 10-15-2012 at 09:40 AM.
Old 10-15-2012, 09:39 AM
  #140  
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the bloke arguing against the point has a mezger in his '1969' 911.
car probably feels out of whack due to the low weight of the original car.
probably needs some gold bullion in the front trunk to even it out.
Old 10-15-2012, 09:41 AM
  #141  
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Originally Posted by Petevb
As you might guess, I weighed a few motors before throwing one in the back.
so, after some research, you acknowledged that the mezger was the right choice...
Old 10-15-2012, 09:56 AM
  #142  
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Originally Posted by 911rox
The Mezger isn't perfect, yes its heavy but it is proven, bullet proof and built in a way whereby it can be rebuilt to like new condition. The replacable cylinder liners provide a platform for having and engine with the same tolerances after the 10th rebuild as the original... This is what makes it sort after and great.
From memory PMNA allows a maximum of three rebuilds on a bottom end, no more, for reliability reasons. True you lack some flexibility, but 100+ lbs more than makes up for it.

Originally Posted by 911rox
If they'd applied the philosophies of the Mezger such as a modular, rebuildable block, true dry sump, etc, etc whilst lightening the new block through incorporated cooling etc (ie Mezger of the 21st century), I'd be very excited...
I don't believe the modularity and light weight are possible together. Bolting the "block" together reduces rigidity and increases weight.

Originally Posted by 911rox
"is the 9A1 the answer we've been looking for?"
I'll withhold judgement until we see it.
Old 10-15-2012, 10:04 AM
  #143  
Petevb
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Originally Posted by aussie jimmy
the bloke arguing against the point has a mezger in his '1969' 911.
car probably feels out of whack due to the low weight of the original car.
probably needs some gold bullion in the front trunk to even it out.
My engined is lightened vs the street car with some of the race car parts, shifted forwards in the chassis, etc. My car has a better weight distribution than a 997 GT3, fyi.

Not better than a 991 GT3, I assume.

But that's not the point. What self respecting sports car guy is willing give up 150 lbs in the wrong place?

Originally Posted by aussie jimmy
so, after some research, you acknowledged that the mezger was the right choice...
The RSR motors are lighter by 30+ lbs, lightweight alternator, carbon intake, inconel exhaust, etc. Unfortunately they need 30 hour rebuilds, so not too practical. So of the available choices the 997 GT3 cup motor was best, significantly lighter than the street motors, and don't get me wrong I love it, both for history and performance. But I absolutely would love it more if it weighed 150 lbs less, and I look forward to having that option in the future.

Last edited by Petevb; 10-15-2012 at 10:27 AM.
Old 10-15-2012, 10:12 AM
  #144  
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the new engine, whatever it is, will have some rather large boots to fill.
here's hoping porsche has an ace up it's sleeve....
hard to believe preuninger will let the team down.
Old 10-15-2012, 01:42 PM
  #145  
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Originally Posted by Petevb
I'll withhold judgement until we see it.
What a novel concept!
Old 10-15-2012, 02:52 PM
  #146  
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Are these out yet? I'm ready to order. Rotors look very nice with big holes.
Old 10-15-2012, 03:08 PM
  #147  
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I want pdk too so i can drink my starbucks and drive too.
Old 10-15-2012, 05:29 PM
  #148  
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Originally Posted by 911rox
Some very good points Petevb but the question is: "is the 9A1 the answer we've been looking for?" If it were built with the same concepts as the Mezger, I'm sure it wouldn't be of concern to most...

The Mezger isn't perfect, yes its heavy but it is proven, bullet proof and built in a way whereby it can be rebuilt to like new condition. The replacable cylinder liners provide a platform for having and engine with the same tolerances after the 10th rebuild as the original... This is what makes it sort after and great. This is also what makes it perfect for category racing in the various cup car series...

The 9a1 unit will be lighter and less complicated and possibly more efficient but how's it going to perform in terms of reliability and how close to factory spec will one be able to restore it when rebuilding? No removable cylinder liners means boring it out and upsizing pistons to suit. In a race car rebuild scenario it will deviate further and further from its original specs resulting in loss of power and compromised reliability?... The couple engine builders/mechanics that I know well and have discussed rebuilding with have both indicated that a rebuilt motor never lasts as long or performs as well as from factory after its been bored/ honed and redone... The factory tolerances just cant be duplicated no matter how good you are... And the M96 and M97 were suppose to be modern engines but we all know how the lasted... The fact is that Porsche's motivation is as much $$ as weight and performance. A mezger costs twice as much as 9a1 as a crate motor yet we won't see a price reduction with the new GT cars... Instead it is expected that we'll see a 5% or so price increase... Hmmmm, gee, wonder why?

If they'd applied the philosophies of the Mezger such as a modular, rebuildable block, true dry sump, etc, etc whilst lightening the new block through incorporated cooling etc (ie Mezger of the 21st century), I'd be very excited... To me it seems however that they have taken the disposable, limited life format of other manufacturers and thats a let down... A lighter engine is awesome but its also gotta last, no?

And as for the Carrera gt and 918, no use comparing the engines in those as they are from a car 5 times the cost.... Ferrari and Lambo, so what? They have great power to weight ratios but can they go to the track week after week and slam out times for 300-400 miles per day? The pro drivers I've spoken to and train with say no and they are blown away each track day when I drive 200 miles to/from the track and slam out a good 3-400 miles on track at pace without it missing a beat... Thats what the Mezger rings to the party IMO... Never been the fastest, but combined with a great chassis, its been the most consistent and reliable...
to quote joe biden, that is a bunch of malarkey.
Old 10-15-2012, 05:39 PM
  #149  
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Originally Posted by Quadcammer
to quote joe biden, that is a bunch of malarkey.
Petervb put forward his reasoning for change, I put forward my reasons for having chosen a mezger based car. Very valid considerations for those of us who decide to hold onto cars as opposed to turning them over every 12 months which isn't necessarily everyone here...

Apologies if its not the same as your opinion, after all you're entitled to your opinion... Oh sorry, what was it again?....
Old 10-15-2012, 06:10 PM
  #150  
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Originally Posted by 911rox
Some very good points Petevb but the question is: "is the 9A1 the answer we've been looking for?" If it were built with the same concepts as the Mezger, I'm sure it wouldn't be of concern to most...

The Mezger isn't perfect, yes its heavy but it is proven, bullet proof and built in a way whereby it can be rebuilt to like new condition. The replacable cylinder liners provide a platform for having and engine with the same tolerances after the 10th rebuild as the original... This is what makes it sort after and great. This is also what makes it perfect for category racing in the various cup car series...

The 9a1 unit will be lighter and less complicated and possibly more efficient but how's it going to perform in terms of reliability and how close to factory spec will one be able to restore it when rebuilding? No removable cylinder liners means boring it out and upsizing pistons to suit. In a race car rebuild scenario it will deviate further and further from its original specs resulting in loss of power and compromised reliability?... The couple engine builders/mechanics that I know well and have discussed rebuilding with have both indicated that a rebuilt motor never lasts as long or performs as well as from factory after its been bored/ honed and redone... The factory tolerances just cant be duplicated no matter how good you are... And the M96 and M97 were suppose to be modern engines but we all know how the lasted... The fact is that Porsche's motivation is as much $$ as weight and performance. A mezger costs twice as much as 9a1 as a crate motor yet we won't see a price reduction with the new GT cars... Instead it is expected that we'll see a 5% or so price increase... Hmmmm, gee, wonder why?

If they'd applied the philosophies of the Mezger such as a modular, rebuildable block, true dry sump, etc, etc whilst lightening the new block through incorporated cooling etc (ie Mezger of the 21st century), I'd be very excited... To me it seems however that they have taken the disposable, limited life format of other manufacturers and thats a let down... A lighter engine is awesome but its also gotta last, no?

And as for the Carrera gt and 918, no use comparing the engines in those as they are from a car 5 times the cost.... Ferrari and Lambo, so what? They have great power to weight ratios but can they go to the track week after week and slam out times for 300-400 miles per day? The pro drivers I've spoken to and train with say no and they are blown away each track day when I drive 200 miles to/from the track and slam out a good 3-400 miles on track at pace without it missing a beat... Thats what the Mezger rings to the party IMO... Never been the fastest, but combined with a great chassis, its been the most consistent and reliable...
The tolerances are JUST good enough to produce these engines on a mass scale... And I strongly disagree with the statement about aftermarket engine assembly never being as good as from the factory. With enough time and money, you can create a much tighter engine than factory.

Some food for thought:

When you bore out the water jackets on a Mezger engine (like when you want to use 105.4+mm pistons), you should find bore center for each cylinder INDIVIDUALLY. If you find cylinder center at one end and machine your water jackets based on theoretical center-to-center spacing of the bores, you run into the risk of having lopsided bores. Thats because the cylinder-to-cylinder spacing isn't perfect...

Just saying.


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