When Porsche 928 S4 was the fastest production car in the world, who beat it?
06-28-2011, 06:23 PM
#46
Race Director
bottom line is the 928's were designed to go very fast, in comfort for hours on end.....and they succeeded in that mission....a nice side effect is a good handling sports car.....
I think the 84 928 was officially clocked in the mid 140's in USA trim.....I know mine has seen over 120mph many times, since I touch between 115-120mph on every single lap.....my guess is its lowly 200whp could hit 140mph easy.....since it reaches 120mph in .4 of a mile...
I had my S4 to maybe 145mph....but it was EASY...since it shifts out of 3rd (auto) at about 140mph....but the acceleration does drop off a bit in 4th....
Another fact....how many 80's "supercars" are still driven HARD today??? Do you see any 80's lambo's or ferrari's in Open Road Racing....or track events....NOPE, never......but you do see 928's having great success in these events for owners of modest means......that speaks volumes to the strength of its design
I think the 84 928 was officially clocked in the mid 140's in USA trim.....I know mine has seen over 120mph many times, since I touch between 115-120mph on every single lap.....my guess is its lowly 200whp could hit 140mph easy.....since it reaches 120mph in .4 of a mile...
I had my S4 to maybe 145mph....but it was EASY...since it shifts out of 3rd (auto) at about 140mph....but the acceleration does drop off a bit in 4th....
Another fact....how many 80's "supercars" are still driven HARD today??? Do you see any 80's lambo's or ferrari's in Open Road Racing....or track events....NOPE, never......but you do see 928's having great success in these events for owners of modest means......that speaks volumes to the strength of its design
06-28-2011, 06:30 PM
#47
Registered User
Join Date: Nov 2010
Posts: 107
Likes: 0
Received 0 Likes
on
0 Posts
I can't see anything from Italy in that era coming close to what the GTS did in terms of a 24 hour speed record.
From: http://www.retrocaricons.com/article/Porsche_928_GTS_62
A standard 928 GTS broke the 24 hour speed record, the car was driven from Austria to Nardo in Italy and a test took place by racing the 928 (undertaken by Franz Doppler and three colleagues). On the track the car averaged 265.74 kmh, once completed the car was driven back home – a testament for the build quality and reliability exhibited by this car.
From: http://www.retrocaricons.com/article/Porsche_928_GTS_62
A standard 928 GTS broke the 24 hour speed record, the car was driven from Austria to Nardo in Italy and a test took place by racing the 928 (undertaken by Franz Doppler and three colleagues). On the track the car averaged 265.74 kmh, once completed the car was driven back home – a testament for the build quality and reliability exhibited by this car.
06-28-2011, 09:22 PM
#48
Addict
Rennlist Member
Rennlist Member
Here is the full text from the section on the Bonneville record. From "Excellence Was Expected" Second Edition, Karl Ludvigsen, pg 1082-1083.
Discuss....
Rich
Bonneville 928
Porsche claimed a top speed for the new model of 270 km/h. The objective was to achieve an officially timed speed at Utah in excess of 170 mph, equal to 274 kp/h. The attack would be made with a 1987 prototype modified slightly as a result of tunnel testing. Changes included an underpan that extended back to the transaxle, omitted exterior mirror, reduced ride height and subtle additions to the bottom of the nosepiece, where brake-cooling inlets were blocked. A cockpit switch gave the air-inlet louvers three positions: shut, 30 percent open and fully open. In the 30-percent position the Cd was 0.29 while with the louvers open it rose to 0.30.
The versatile Walter Naher engineered the Bonneville effort. Seven-inch-wide rims at all four corners were to be fitted with Pirelli P700 tires that were scuffed to provide a minimal tread depth and pumped up to 64 psi. Bilstein dampers were specified and a stiffer (30 x 5 mm) front antiroll bar installed. Although it was not ready for the preliminary tests, a new 2.54:1 ring and pinion was installed for the Utah runs, replacing the 2.64:1 ratio that had been the highest previously available.
Prototype G18 was readied for testing in March and in early April Naher took it to the Nordo circular track in Italy. Ideally the runs would be made with the 30-percent-open louver setting but this turned out to be unfeasible when engine-water exit temperture rose to 106 degree C. With the jalouise fully open the exit temperature fell to an optimal 98 degrees C. Even with this added drag the 928S4 romped around Nardo's bowl at 176.2mph clockwise and 181.8mph counterclockwise. The difference was attributed to roadway unevenness and wind effect.
After these successful tests on April 5 and 6, 1986, the 928S4 was fitted with its higher rear axle ratio, which was aimed at matching peak power with peak speed. At Nardo the engine had been bumping up against its controlled limit of 6,500 rpm. By the end of April the car was ready for shipping to the United States, where Walter Naher supervised the runs. Al Holbert took the wheel at Bonneville in August, when the salt was at its best. On August 7 he was officially timed by USAC, under the auspices of the FIA, at an average of 171.110 mph for the flying mile and 171.926 mph for the kilometer. It was official; Porsche could declare the 928S4 the world's fastest catalyst-equiped car.
Porsche claimed a top speed for the new model of 270 km/h. The objective was to achieve an officially timed speed at Utah in excess of 170 mph, equal to 274 kp/h. The attack would be made with a 1987 prototype modified slightly as a result of tunnel testing. Changes included an underpan that extended back to the transaxle, omitted exterior mirror, reduced ride height and subtle additions to the bottom of the nosepiece, where brake-cooling inlets were blocked. A cockpit switch gave the air-inlet louvers three positions: shut, 30 percent open and fully open. In the 30-percent position the Cd was 0.29 while with the louvers open it rose to 0.30.
The versatile Walter Naher engineered the Bonneville effort. Seven-inch-wide rims at all four corners were to be fitted with Pirelli P700 tires that were scuffed to provide a minimal tread depth and pumped up to 64 psi. Bilstein dampers were specified and a stiffer (30 x 5 mm) front antiroll bar installed. Although it was not ready for the preliminary tests, a new 2.54:1 ring and pinion was installed for the Utah runs, replacing the 2.64:1 ratio that had been the highest previously available.
Prototype G18 was readied for testing in March and in early April Naher took it to the Nordo circular track in Italy. Ideally the runs would be made with the 30-percent-open louver setting but this turned out to be unfeasible when engine-water exit temperture rose to 106 degree C. With the jalouise fully open the exit temperature fell to an optimal 98 degrees C. Even with this added drag the 928S4 romped around Nardo's bowl at 176.2mph clockwise and 181.8mph counterclockwise. The difference was attributed to roadway unevenness and wind effect.
After these successful tests on April 5 and 6, 1986, the 928S4 was fitted with its higher rear axle ratio, which was aimed at matching peak power with peak speed. At Nardo the engine had been bumping up against its controlled limit of 6,500 rpm. By the end of April the car was ready for shipping to the United States, where Walter Naher supervised the runs. Al Holbert took the wheel at Bonneville in August, when the salt was at its best. On August 7 he was officially timed by USAC, under the auspices of the FIA, at an average of 171.110 mph for the flying mile and 171.926 mph for the kilometer. It was official; Porsche could declare the 928S4 the world's fastest catalyst-equiped car.
Rich
06-28-2011, 09:53 PM
#49
Addict
Rennlist Member
Rennlist Member
Here's my data point... I've driven my 1987 S4 in the Pony Express ORR in Nevada, (probably slightly lower altitude as Bonneville). I made it up to 160+mph with 2.20:1 ratio gearbox. There is a speed "hole" with the 2.20:1 gearbox. You simply can't accelerate much at those speeds, your RPM's aren't high enough. Takes some time to slowly climb up to 160+mph.
Did the Bonneville car have the 2.54:1 at the time for the record attempt? I don't know....didn't Kibort have a 2.20:1 in it when he got it? Was it swapped out again at some time? Somebody plug in the numbers with 2.54:1 and see what the top speed might be (I don't have the calc program).
After the section on the Bonneville record, the book describes several magazines achieving 159-165mph top speeds, but none got near 171mph. Not surprising to me, they surely had the 2.20:1 box as well.
In a stock 1987 S4, add some strategically placed duct tape, lower the ride height, remove the mirrors and wipers, skinny tires, looooong Nevada desert straights, cool morning, no wind....yeah, 170+mph is possible. 180+mph? Hmmmm.....
Another data point regarding final drive ratio...George Suennen didn't install a 2.20:1 rear end in his super-charged ORR car until he had enough HP at lower RPM's (5,000rpm or so) to make it out of the speed hole.
Rich
Did the Bonneville car have the 2.54:1 at the time for the record attempt? I don't know....didn't Kibort have a 2.20:1 in it when he got it? Was it swapped out again at some time? Somebody plug in the numbers with 2.54:1 and see what the top speed might be (I don't have the calc program).
After the section on the Bonneville record, the book describes several magazines achieving 159-165mph top speeds, but none got near 171mph. Not surprising to me, they surely had the 2.20:1 box as well.
In a stock 1987 S4, add some strategically placed duct tape, lower the ride height, remove the mirrors and wipers, skinny tires, looooong Nevada desert straights, cool morning, no wind....yeah, 170+mph is possible. 180+mph? Hmmmm.....
Another data point regarding final drive ratio...George Suennen didn't install a 2.20:1 rear end in his super-charged ORR car until he had enough HP at lower RPM's (5,000rpm or so) to make it out of the speed hole.
Rich
06-28-2011, 10:00 PM
#51
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Worth mentioning that "Magazine Tests" often are based on .......NOTHING. Just the writers imagination or poorly calibrated equipment, unscientific sampling or based on manufacturers numbers. They write for entertainment value and to solicite advertising !!
06-28-2011, 10:07 PM
#52
Instructor
Join Date: Aug 2010
Location: Greeley co
Posts: 205
Likes: 0
Received 0 Likes
on
0 Posts
From what I have read about the countach, if Lamborghini would have done the same preparing for top speed runs as Porsche it would have blown past 190.
I guess it all depends on your definition of fastest production car whether 928 qualifies. I think they would need to be compared in a fair test. As it is we have a modified car meant for top speed testing by Porsche versus actual factory produced cars tested by magazines not modified for top speed.
To me I think it is misleading to claim 928 as the fastest based on the 181 top speed.
I guess it all depends on your definition of fastest production car whether 928 qualifies. I think they would need to be compared in a fair test. As it is we have a modified car meant for top speed testing by Porsche versus actual factory produced cars tested by magazines not modified for top speed.
To me I think it is misleading to claim 928 as the fastest based on the 181 top speed.
06-29-2011, 10:39 AM
#54
Drifting
Here is the Nardo test track
The reason companies test here is clear from the design. It is a large circle that is banked all-around. What this means is this, you don't ever have to lift off the gas pedal, it is like being on an endless straight-away. It also has a solid surface.
Bonneville is made of salt particles. That is why Holbert was nervous before taking the car out for the test. It is also the reason why Jeremy Clarkson said it runs a few mph slower than pavement. Grip is not perfect so traction suffers, and straightline control suffers. That can scrub some time. The lowering of the car may have had something to do with trying to create a venturi effect for directional stability. Bottom line I have driven my S2 at 160 on pavement and it had more to go. I have 2.54 gearing.
Thanks Richard for that more complete posting of the record. BTW the S2 that ran 160 on track at Nardo for 24 straight hours did so with a Flag mirror, no lowering, and no body mods!
The reason companies test here is clear from the design. It is a large circle that is banked all-around. What this means is this, you don't ever have to lift off the gas pedal, it is like being on an endless straight-away. It also has a solid surface.
Bonneville is made of salt particles. That is why Holbert was nervous before taking the car out for the test. It is also the reason why Jeremy Clarkson said it runs a few mph slower than pavement. Grip is not perfect so traction suffers, and straightline control suffers. That can scrub some time. The lowering of the car may have had something to do with trying to create a venturi effect for directional stability. Bottom line I have driven my S2 at 160 on pavement and it had more to go. I have 2.54 gearing.
Thanks Richard for that more complete posting of the record. BTW the S2 that ran 160 on track at Nardo for 24 straight hours did so with a Flag mirror, no lowering, and no body mods!
06-29-2011, 10:54 AM
#55
Addict
Rennlist Member
Rennlist Member
What it looks like:
Problem with Lamborghini Countach speeds is that no one outside factory got anywhere near 190. Reason is probably simple. At the time Lambo had habbit of making special engines for press cars. They had more hp than average production model.
Problem with Lamborghini Countach speeds is that no one outside factory got anywhere near 190. Reason is probably simple. At the time Lambo had habbit of making special engines for press cars. They had more hp than average production model.
06-29-2011, 12:33 PM
#56
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Right, traction at Bonneville is a big issue one reason why 7 inch rims were used on the Holbert run. Narrow tires are less likely to "hyroplane" on the loose particles much as snow tires are better when narrow. Air temperature and humidity levels also have a big impact on horsepower all of which means top speed is no fixed number but what happened at that place that day in those conditions.
06-29-2011, 05:30 PM
#57
Race Director
From what I have read about the countach, if Lamborghini would have done the same preparing for top speed runs as Porsche it would have blown past 190.
I guess it all depends on your definition of fastest production car whether 928 qualifies. I think they would need to be compared in a fair test. As it is we have a modified car meant for top speed testing by Porsche versus actual factory produced cars tested by magazines not modified for top speed.
To me I think it is misleading to claim 928 as the fastest based on the 181 top speed.
I guess it all depends on your definition of fastest production car whether 928 qualifies. I think they would need to be compared in a fair test. As it is we have a modified car meant for top speed testing by Porsche versus actual factory produced cars tested by magazines not modified for top speed.
To me I think it is misleading to claim 928 as the fastest based on the 181 top speed.
Whats interesting is Porsche says the nardo car was fitted with a 2.64 rear end and was hitting the limiter at 181mph......using this calculator
http://www.autolounge.net/calculators/gearing.html
with a 245/45-16 tire that equals 180.7mph.....with a 225/50-16 its 182.0....exactly what Porsche claims.....
06-29-2011, 06:46 PM
#58
Nordschleife Master
I am going out on a limb here and saying that is a highly optimistic speedo there... Unless there was full on timing gear checking that or at the very least GPS confirmation 160 and room to go from an S2 seems unlikely...
06-29-2011, 08:06 PM
#59
Three Wheelin'
Thread Starter
Its an euro twin dizzy, so it could get close to that number, no ????
06-29-2011, 08:45 PM
#60
Addict
Lifetime Rennlist
Member
Lifetime Rennlist
Member
James they just drove 3,840 miles in 24 hours no need for GPS or fancy timing equipment just count the laps 
and who cares what the speedo says or reads ! Good chance they ran it without cats too...and we KNOW Porsche has used tweeked chips in the past.
and who cares what the speedo says or reads ! Good chance they ran it without cats too...and we KNOW Porsche has used tweeked chips in the past.