Audi r8 vs Gt weight

[californiacuda]

It seems that the 150 lbs number is a good estimate of the weight for the supercharger system. In a perfect world wouldn't a 150lb supercharger on a decent size v8 be the wrong way to go if the goal was only 550 hp.

The Corvette makes over 500 with a normally aspirated engine. So if Ford has chosen to put in an engine similar to the LS6, then the GT would have weighed 3450-150=3300lbs with 50 less hp and been able to sell the car for much less $.

The gain from adding the supercharger (50 hp) was not worth the extra weight(150 lbs) in stock form.

I am very glad that Ford left us so much room to add a device like the Whipple and get to 750whp with hardly any effort. But as a stock vehicle it seems a better choice to either use a lighter v6 with forced induction or use a naturally aspirated V8.

Now I know that each manufacturer can only use what's in its own bag of magic tricks, but I was just trying to do an analysis of the supercharger focusing on weight.

 

[dbk]

When I say raw, it has nothing to do with gadgets. Drive a 996 GT3 then tell me which is more raw. The last one I was in was a Euro Spec car, but it was nowhere near as quiet or smooth as the GT.

But either way, I don't know what you're looking for here. Do you want to know why the car has roughly equal weight to an R8? I thought we've established several times already in the thread that the supercharger adds significant weight. A GT is longer and wider. It carries larger tires. The modular motor is HUGE. I can't guarantee it, but I've seen the 5.4 mod out of an engine bay, and I can't imagine whatever the Audi has weighs more.

Armed with that knowledge, what are you trying to do? Do you just want to know why it weighs what it weighs for academic purposes, or are you trying to make it a road racer? A 997 Turbo weighs even more than a GT. Either way, a GT will blister both.

 

[dbk]

Now I know that each manufacturer can only use what's in its own bag of magic tricks, but I was just trying to do an analysis of the supercharger focusing on weight.

If this is your question I can tell you exactly why they chose the supercharger. They considered a couple different engine options.

They picked the twin screwed 5.4 because a) it's so smooth (it certainly has a less frenetic character than the LS7 or 8500rpm flat 6) and b) they were aware that it could be made faster than an Enzo with almost no effort.

John Coletti was the boss at SVT when this car was made. OJC chose the motor that could best be made to haul the most ass with the least impact on the character of the car. Add a pulley and tune and the car will go 135mph in the 1/4 with no discernible change in driveability.

 

[californiacuda]

I have driven the 997 gt3, the US version, not the euro spec version and it is a damm nice car that with the new electronic suspension system is pretty ok on the street with the touch of a button.

I'm sorry that my thoughts and analysis of weight and performance have disturbed you so much. I guess understanding performance cost/benefit in the GT and other cars seems to ruffle your feathers. I just think that it benefits all of us to see +'s and -'s of different items on the GT and other cars.

Why do you need to get so bent?

 

[dbk]

I'm sorry that my thoughts and analysis of weight and performance have disturbed you so much. I guess understanding performance cost/benefit in the GT and other cars seems to ruffle your feathers. I just think that it benefits all of us to see +'s and -'s of different items on the GT and other cars.

Why do you need to get so bent?

I think you're misreading me here bud :lol I'm not "bent". I just didn't know what you're trying to get at. From your original post it appeared it was a question of why the R8 and GT carry similar weight. I thought we established that a lack of AWD was made up for by an increase in size and largely the weight of the supercharger system.

When it moved onto other cars, I was literally trying to find out what the point was. If you were just doing a cba of putting a supercharger on the car, that works for me. I just didn't know if you were asking some purely academic question(i.e why does a GT weigh what it weighs), or were trying to find a way to lose weight to make your car more of a road racer or what.

Cool? :cheers

 

[FlorIdaho Chris]

I know this thread is about the Audi vs GT weight, but since the GT3 has been brought up I need to add my comment.

I ran a track day at Homestead today with two GT3's present and I was not impressed. It could have been the drivers, but I could blow these porkers away with my little Lotus 240R. Yeah they could take me on the straights, but overall I was maybe three to four seconds a lap faster. I expected much more from the new GT3 at the track. :thumbsdow

 

[californiacuda]

MY first line of thinking was to understand the weight of the GT which with its aluminum frame and body had always seemed too heavy. The discussion about the blower weight was enlightening. I then thought about the benefit of the hp/weight of the sc and came to the conclusion that in a perfect world, in stock form, it wasn't worth it, for only 50 lbs.

Once the hp is stretched with the aftermarket blower for relatively small money and effort, the weight to hp ratio of 3450/850= 4:1 puts the car in a very exclusive group.

I find this forum informative and I was simply trying to participate on a subject that I found interesting and maybe others too.:thumbsup

 

[dbk]

Gotcha.

It's pretty clear they left a ton of power on the table intentionally. Not having any kind of stability control, they are being totalled quickly with only 550hp. They could have easily made them leave the factory with 650, but it probably would have proved nightmarish quickly.

Also, to obtain the level of driveability, reliability of the GT, you couldn't have done it as easily N/A. At least not in the timeline they had to deliver. The LS7 is the product of years of shared tech with the racing program, and I'm sure the Porsche shares it as well. The GT had a very, very, very short gestation period. And not with the flexibility of the current engine. Not many cars can add 150rwhp and still be smog legal.

I also think it benefits from the weight on the big end. Obviously part of it's superior aero, but I never felt comfortable at 160+ in my Z06 (big cube C5). The GT feels much more planted 40 mph faster.

If it were ever going to have been a real race car, it would have made much more sense to be N/A. But because it wasn't ever going to be campaigned, it was less of a concern. Just as an aside, a twin turbo system was also considered.

 

[FlorIdaho Chris]

Dave-

Do you know why the twin turbo idea was dropped? Cost?

 

[BlackICE]

With today DOT regulations cars are getting heavier all the time. I was disappointed by the GT's heft, but after owning it and examining the material and construction. They isn't a lot of things Ford could have done to save more weight and meet regulations too. The Noble and Ariel are light because they don't have any regulations to meet.

We might get a better idea on how light the GT could have been if built to 60s regulations, by seeing what a GT converted for racing weighs.

I suspect you can save a lot of weight by eliminating the sound proofing, side impact protection, air bags, Cats and exhaust manifolds, vapor recovery system, electric windows, etc. But then it wouldn't be a street car. All of the Porsches are porkers too, with the exception of the GT3.

I am glad that Ford put a blower in the car, with very stout engine internals. Very easy and inexpensive to mod to over 700+ horsepower and that puts the GT in a very exclusive club even at is weight.

 

[dbk]

Dave-
Do you know why the twin turbo idea was dropped? Cost?

Time constraint and what was already in the playbook. A blown 5.4 was still in the Lightning when this all started. It would have taken too much effort in a project already pushed to the limit to develop a completely new system, TT or n/a. Had this happened now, with the TwinForce actively on deck? Who knows. The weight saving, better cooling, and less stress of the TT are definitely attractive.

 

[DoctorV8]

The Corvette makes over 500 with a normally aspirated engine. So if Ford has chosen to put in an engine similar to the LS6, then the GT would have weighed 3450-150=3300lbs with 50 less hp and been able to sell the car for much less $.

The gain from adding the supercharger (50 hp) was not worth the extra weight(150 lbs) in stock form.

Well, as DBK alluded to, Ford had/has no engine comparable to the Z06's LS7. And the grossly undersquare 5.4 with its tiny bore and trucklike stroke is capable of neither the RPM nor the airflow needed to make over 500 HP naturally aspirated AND meeting OEM durability standards....at least not without a lot of R&D.

I agree that a clean sheet high revving n/a V8 would have been a great lightweight alternative, but the positive displacement blower on the GT is a very successful and proven recipe for tons of power....a route that even the Blue Devil Corvette seems to be following.

 

[Tungsten]

R8...What it is like to drive

I had the good fortune of spending the day driving the new Audi R8 in Nevada. I drove 3 hours through the surrounding mountains and desert and then 3 hours on the track at Las Vegas Motor Speedway. They had a small tight road course that we ran.

The Audi is a very unique car from my limited experience. It is something less than a Lambo in power and growl. It is more sophisticated than a GT, but lacks that jaw dropping impact of the GT. Easier to drive than a Lambo, more of a cruiser than a race car. Great workmanship and finish.

Not enough power. The V8 at 420 HP just does not get it done. Don't get me wrong, it is a fun car to drive and with more HP would be world class. It just is not there yet. The technology in the car exceeds any car I have owned, including Porsche Turbo.

Only 70 coming to the States this year, about 2 per dealer that have signed up for the updated show room and service facility. That will make them rare in 2007 in the US. According to the brand manager for the car, there will be a V-10 version announced in 08. They are waiting for Lambo to take the current V10 power plant up in HP and then Audi will use the current Lambo V10. They were clear that they would not have the same HP of the Lambo.
They are also scheduled to announce a spyder version in 08 as well.

So here is the net....great car, great car to drive every day. It is not a GT.
Amazing technology, great B&O 1000 watt stereo, with no hump!!
Did not like the gated shifter, did like the paddle shifter. Add the V10 and you will have a real car.
Don:thumbsup

 

[FlorIdaho Chris]

I had the good fortune of spending the day driving the new Audi R8 in Nevada. I drove 3 hours through the surrounding mountains and desert and then 3 hours on the track at Las Vegas Motor Speedway. They had a small tight road course that we ran.

The Audi is a very unique car from my limited experience. It is something less than a Lambo in power and growl. It is more sophisticated than a GT, but lacks that jaw dropping impact of the GT. Easier to drive than a Lambo, more of a cruiser than a race car. Great workmanship and finish.

Not enough power. The V8 at 420 HP just does not get it done. Don't get me wrong, it is a fun car to drive and with more HP would be world class. It just is not there yet. The technology in the car exceeds any car I have owned, including Porsche Turbo.

Only 70 coming to the States this year, about 2 per dealer that have signed up for the updated show room and service facility. That will make them rare in 2007 in the US. According to the brand manager for the car, there will be a V-10 version announced in 08. They are waiting for Lambo to take the current V10 power plant up in HP and then Audi will use the current Lambo V10. They were clear that they would not have the same HP of the Lambo.
They are also scheduled to announce a spyder version in 08 as well.

So here is the net....great car, great car to drive every day. It is not a GT.
Amazing technology, great B&O 1000 watt stereo, with no hump!!
Did not like the gated shifter, did like the paddle shifter. Add the V10 and you will have a real car.
Don:thumbsup

Thanks for the write up Don. I had been waiting to hear your impressions. So the question is are you taking delivery of an '07 or waiting for the V10?

 

[911teo]

Time constraint and what was already in the playbook. A blown 5.4 was still in the Lightning when this all started. It would have taken too much effort in a project already pushed to the limit to develop a completely new system, TT or n/a. Had this happened now, with the TwinForce actively on deck? Who knows. The weight saving, better cooling, and less stress of the TT are definitely attractive.

Throttle response is the worse enemy of a Turbo solution.

It is interesting how the GT is the only exotic (if you leave the Bugatti, but it was built with only one goal so it is a different story) that makes use of force induction.

The last turbocharged F-car was the F40. Only NA V12 for Lamborghini. Even Porsche that argualbly had the heritage of a turbo car went the NA route for their supercar.

Also the trend in the automotive industry is to drop SCs and Turbos in favor of high revving NA engines. Mercedes-benz dropped the SC 5.5 in favor of the 6.3L V8 for their AMG lineup.
Audi went with a big capacity V8 for their RS models.
Porsche's drivers' 911 is the NA GT3.

The advantage of the SC in the GT is that 80% of the torque is avaliable at 2,000rpm.
This makes easy and relaxing to drive even in traffic (try and do that with a Carrera GT).
It also allowed Ricardo to choose a rather silly set of ratios for the gears as for every intent 6th is useless.

In my perfect world the F-GT would have a 8,500 rpm V10 behind the glass.

And weigh 400lbs less....

We are not in a perfect world and I am keeping my GT as is.

 

[SteveA]

Sometime back I put my car on a small diet and posted the results.

As I recall, the car had a Borla, light weight rim option, removed the rubber mats and installed custom fit 38oz carpet, bumper delete, removed the tow & tire kit, Mac delete, child seat bracket delete. I topped off the fuel tank and took the car next door to a scale that is certified to + or -5lbs. I then mathematically removed the weight of the gas and came up with 32900. I have sense removed the Borla and installed a X pipe but haven't been back to a scale.

 

[Tungsten]

R8 yes or no...

Chris,
I have one of each on order. I am number 7 on the list for the V8, number 2 on the list for the V10 and number 1 on the list for the spyder. All that means is that I gave them $ 500 for each order, refundable. The ideal for me would be a V10 Spyder. I cannot afford a 430 Spyder to this may be the best bet for me. I would not take delivery of the V8 unless they could get it to me asap and that is not going to happen....so I am waiting for a V10...hopefully a spyder. I am looking for a daily driver and this appears to be a good choice for me.
Don

 

[dbk]

Awesome choice for a daily driver Don! I had no idea they were going to be so rare in the U.S.

Very interesting to see how they are managing the R8 vs. Gallardo situation.

 

[fjpikul]

Tungsten, what happened to the diesel option? Is it still in the distant cards?

 

[FlorIdaho Chris]

Chris,
I have one of each on order. I am number 7 on the list for the V8, number 2 on the list for the V10 and number 1 on the list for the spyder. All that means is that I gave them $ 500 for each order, refundable. The ideal for me would be a V10 Spyder. I cannot afford a 430 Spyder to this may be the best bet for me. I would not take delivery of the V8 unless they could get it to me asap and that is not going to happen....so I am waiting for a V10...hopefully a spyder. I am looking for a daily driver and this appears to be a good choice for me.
Don

Sounds like a great plan Don. I look forward to hearing more about whatever you eventually end up with. :thumbsup