36 replies to this topic

[biercemountain]

After watching the Audi's dominate sports car racing for the past few years I find myself wondering how a Porsche 913/30 Can Am car would fare against the Audi R8. I would imagine the handling and aerodynamics would be superior in the Audi but would that be offset by the brute horsepower of the Porsche?

Any thoughts?

[Ross Stonefeld]

What was race sustainable HP on the 917? the R8 has about 600 on a restricted engine in a 1000kg body.

[da Silva]

It´s a nice thought. At an race at the [old] Hockenheim track my cent would go to the 917/30.
1100 hp on the paper, it´s quite more accualy. Porsche dyno at that time only went to 1100hp that´s why the figure

[SKL]

I'd give anything to see Mark Donohue duke it out with Michele Albereto- 917 vs R8. Lets say, Road America. I'd give it to the ultimate Porsche! That Sunoco 917-30 was awesome, but that R8 is pretty impressive too...

[312 PB]

917/30 puts about 1300bhp
to the ground

[Ross Stonefeld]

Does the 917 get 2002 technology tires?

[El Tapatio]

For raw top-end speed, give the edge to the Porsche. But the Audi will eat it for lunch in just about every other category. Much better brakes, better fuel consumption, more tractable power curve, quicker shifting, and, especially important in endurance events, MUCH quicker to work on in the pits. The Audi would most likely post better lap times, more consistently, and for a longer period of time. It would also spend a fraction of the Porsche's time in the pits. Isn't progress wonderful?

[Ross Stonefeld]

Yeah, you can replace an entire Audi in less time than it takes for a car to finish a lap

[Viss1]

According to Pete Lyons' Can-AM, "...power reached 1100 at 7800 (RPM). More boost, of course, gave even more power; readings above 1500 were seen on the dyno." The Porsche was capable of 240MPH in 1973. Two years later, the car hit 250 while breaking the World's Closed Course Speed Record at Talladega. I'd love to see that baby in action on the Mulsanne straight...

[biercemountain]

Originally posted by SKL
I'd give anything to see Mark Donohue duke it out with Michele Albereto- 917 vs R8. Lets say, Road America. I'd give it to the ultimate Porsche! That Sunoco 917-30 was awesome, but that R8 is pretty impressive too...

Who knows, maybe Mark and Michele are duking it out now in that great race track in the sky.

[Viss1]

Originally posted by biercemountain


Who knows, maybe Mark and Michele are duking it out now in that great race track in the sky.

And Michele is pissed because Mark won't let him touch the boost knob...

[bleakuzs]

if left in the orginal forms, the R8 would destroy the 917/30

[Alien]

Hmmm well let´s see some numbers:



from http://www.cknet.org...ecification.htm

1973 Porsche 917/30 Cam Am

Engine : Flat 12 turbocharged (max boost 1.5 bar)
Capacity : 5,374cc
Bore / Stroke : 90mm / 70.4mm
Compression ratio : 6.5:1
Maximum power : 1,100bhp @ 8,000rpm
Maximum torque : 1,098 Nm @ 6,400rpm
Brakes : Cross drilled and venilated discs with drilled aluminium hubs.Porsche aluminium four-piston calipers
Wheels : Front - 12" x 15" Read - 19" x 15" cast magnesium alloy wheels with centre nut and air-extractor cones (hub-caps !)
Tyres : Goodyear
Dimensons : Length - 4,562mm Width - 2,085mm Height - 730mm
Wheelbase : 2,500mm
Track : 1,670mm (front) 1,564mm (rear)
Turning circle : 13m
Unladen weight : 845kg (33/67 front/rear split)
Fuel tank capacity : 400 Litres
Fuel Consumption : 85 Litres/100Km (or 3.4 miles per gallon)
Maximum speed : kph / 238mph
Acceleration : 0-60 mph : 2.1seconds 0-100mph : 3.9 secs 0-200mph : 13.4mph

from: http://www.mulsannes.../audir8-01.html

2001 Audi R8 Specifications

Engine: V8, turbo-charged, 90 degree cylinder angle, 4 valves per cylinder, 2 Garrett turbo-chargers; to comply with the rules 2 x 32.4 mm air restrictors, and boost pressure restriction to 1.67 bars (absolute)
Engine management: Bosch MS 2.8
Engine lubrication: Dry sump, Shell Racing Oil SR
Displacement: 3600 cc
Horsepower: 610+ hp
Torque: 516 lb-ft.
Power transmission: Rear-wheel drive
Clutch: CFC clutch
Gearbox: Sequential 6-speed sports gearbox, partner Ricardo
Differential: Multiple-disc limited slip differential
Driveshafts: Constant-velocity plunging tripod joint
Steering: Power-assisted rack-and-pinion steering
Suspension: Independent suspension at front and rear. Double-wishbone suspension. Pushrod system with horizontal spring/damper unit, adjustable gas-filled shock absorbers
Brakes: Hydraulic dual-circuit brake system, monobloc light-alloy brake calipers, ventilated carbon fiber brake discs at front and rear, brake force distribution, driver adjustable
Wheels: O.Z. forged magnesium rims, Front: 13.5 x 18 inches, Rear: 14.5 x 18 inches
Tires: Michelin Radial, Front: 33/65-18, Rear: 36/71-18
Length: 4650 mm
Width: 2000 mm
Height: 1080 mm
Wheelbase: 2730 mm
Front Overhang: 900 mm
Rear Overhang: 1020 mm
Weight: 900 kgs
Tank capacity: 90 liters

The porsche doesn´t look so bad, maybe if you give the R8 old tyres or give the porsche new ones, who knows!

Let´s say we give them equal tyres, what would you say then?

[Viss1]

Cool pics, Alien. I didn't realize the Porsche was lighter than the Audi. My guess is the Audi might take it on a slower, twisty course, but the power sections would be all Porsche.

[BRG]

Despite being a TNF regular AND a Porsche fan, I fear that the truth is that the Audi would chew up and spit out the 917/30 without a problem.

But to settle it, surely both have raced on some of the same tracks in the US - can anyone find lap times from somewhere where the circuit remains unchanged?

[GunStar]

I bring up the tire issue. The 917 CAN'T take new tires. Even in the mid 70's when tires hadn't progressed that much, a "new" 917 was built to comply to the interim open cockpit prototypes. This car was fast, but with the grippier tires, it just ripped up the chassis. Now, the R8R should be able to take the older style tyres. Just get a set of Avons built to fit and go from there.

As much as I love the 917, regretably, I must hedge my bets with the Audi on everywhere but the highest speed tracks. The 917 was a horrible pig to control at best. Raw horsepower can only get you so far. Now, I've only driven a 917K so I can't speak on the 917/30K.

In case your wondering where, knowing people at Historic autoraces really pays dividends.

[biercemountain]

Originally posted by GunStar
Now, I've only driven a 917K so I can't speak on the 917/30K.

In the words of Wayne and Garth "I'm not worthy, I'm not worthy"

You lucky bastard!

[wati]

Fuel tank capacity : 400 Litres

Where did they put such an amount of fuel?

Wattie

[AndreasNystrom]

wow, i will also worship GunStar now

917 is the most amazing racingcar ever built. Everything started as a small kid, when I got
collector pictures of various sportscar. One of them had a Ferrari 512, and the other just looked so much cooler, it was the Porsche 917, then i continued to read things like topspeed over 400km/h, and was pretty amazed, since my dads Volvo 142 barely did 100km/h. =)

[AlesiGOD]

I look forward to trying this in the World Sports Cars game...

[LuckyStrike1]

If a 28 year old racingcar stands a chance to a modern racingcar - then there is something seriously wrong.

[Alien]

A good read, from: http://www.tavlecent...he/Racecars.htm

Porsche’s management was now comfortable with Donohue and Flegl and gave them the green light to build a completely new car for the 1973 season. Porsche called it the 917/30, while Mark Donohue called it "a monument to my career". Competitors called its turbocharging unfair and by any name it was a car that raised the ante so high that it took the rule-makers to beat it. Work began on the 917/30 before the 1972 season ended and intensified during the winter as every lesson learned developing the 917/10 was incorporated into the new design. The first three 917/30s built had nothing in common with its predecessor though. Not even its dimension were the same, the alloy frame was six inches longer than the 917/10. Its track was five inches wider in front and one-and-a-half inch narrower in the rear. Its new body, designed by a French aircraft consulting firm and later modified by Flegl and Donohue in the field during testing at the Paul Ricard Circuit, proved one of Donohue’s hunches correct when he hit 398,4km/h on the long straight. The 917/30 powerplant was the familiar air-cooled, 12-cylinder twin turbocharged seen in the last 917/10, except now it was enlarged to 5.4 liters and made an incredible 1000bhp. Later, with an adjustable boost screw installed, it pumped out almost 1100bhp at full boost.

The 917/30 retained the air-cooled, 12-cylinder, twin turbocharged engine configuration from the Type 910, but it was enlarged to 5.4 liters and an overwhelming 1090bhp. A later turbo boost adjustment produced an astounding 1700 horsepower.

With little competition, it appeared there was no way the mighty new Porsche could lose at the season opener at Mosport, Canada. Racing being what it is, it did lose the season opener after Donohue tangled with a slower car, and a 917/10 from the previous year won the race. Donohue came in seventh. In the second race at Road Atlanta he lost again (because of a leaky fuel cap) and the second loss added further embarrassment to what was supposed to be the world’s greatest sports racing car. During practice and qualifying for the third race, while cresting on a hill, an alloy rear lower A-arm broke backed into a guardrail at 240km/h. He walked away visibly shaken, a condition noted by sharp-eyed competitors. What happened next however rocked everyone who ever dreamed of beating Donohue and the 917/30, and forever changed Can-Am.

After the crash, Porsche 917/30-002 was towed to the garage area and covered. Donohue regained his lost composure while the crew rolled out Porsche 917/30-003, from the transporter. Donohue called to drive, strapped himself into his specially designed seat and chugged onto the track. Two laps later he shattered the lap record in what competitors thought was only a back-up car. The next day the 917/30 easily won its first Can-Am race. From that point on, it was no contest, the car some call "The Picasso of Porsche" won the next six Can-Am races and the 1973 Championship.

Donohue announced his retirement at Riverside after the final Can-Am in 1973. Several months later the group that sanctioned the series revised the rules for turbocharged cars, limiting fuel capacity, a move that hobbled the thirsty 917/30s against the competition. Porsche withdrew from the series for a final time. Ironically Donohue’s final triumph before his death was in the 917/30. Penske asked Donohue to settle a bet for him in 1975 by trying to break a one-lap average speed record of 348km/h set by A.J Foyt. Donohue and his most famous car, the 917/30, now modified with intercoolers, teamed up at Talledega in Alabama. No one, including Donohue, who returned to the US from his home in the UK, regarded it as a priority. Donohue took only one lap, checking the 917/30s complex systems before he stuck his foot on the floor. The flying 917/30 burst from the gloom of the fourth turn and, in a great wail, screamed down the front straight at a speed estimated at close to 400km/h. Entering the first turn, Donohue feathered the throttle. The car wobbled slightly, the result of flattening the big rear wing for maximum speed, and disappeared from the sight of the spectators waiting in the pitlane. You could hear its revs pick up between the turns and down the back straight until once again the 917/30 burst into view and flashed across the start/finish line to set a record of 353,792km/h, a record that stood for four years until May 1979. Donohue came in on the next lap, sat for a few pictures, smiled a lot, and said his goodbyes. A few days later, on August 12, 1975, he died after crashing a Formula 1 car at the Österreichring in Austria.

[Alien]

Originally posted by GunStar
Now, I've only driven a 917K so I can't speak on the 917/30K.

0-60 in 2.7 seconds!!!!!!!!! WOW!!!!

from: http://www.cknet.org...ecification.htm

1971 917 K (Gulf)

Engine : Flat 12 air-cooled
Capacity : 4,998cc
Bore / Stroke : 86.8mm / 70.4mm
Compression ratio : 10.5:1
Maximum power : 630bhp @ 8,300rpm
Maximum torque : 589 Nm @ 6,400rpm
Brakes : 12-inch cross drilled & vented discs with drilled aluminium hubs. Girling aluminium four-piston calipers
Wheels : Front - 10.5" or 12" x 15" Read - 15" or 17" x 15" five-spoke cast alloy wheels with centre nut
Tyres : Firestone
Dimensons : Length - 4,120mm Width - 2,080mm Height - 940mm
Wheelbase : 2,300mm
Track : 1,582mm (front) 1,584mm (rear)
Turning circle : 13m
Unladen weight : 800kg (36.5/63.5 front/rear split)
Fuel tank capacity : 120 Litres
Fuel Consumption : 48 Litres/100Km (or 5.95 miles per gallon)
Maximum speed : 350kph / 220mph (394kph / 246mph for longtail)
Acceleration : 0-100kph : 2.7 seconds


I also checked the 400 liter tank on the 917/30 and it pops-up everywhere on the internet.

[POLAR]

Anyway, the 917k is/was a true legendary piece of machinery. I'd rather have it in my garage than the R8. (That is nice too.)

Polar

[Cociani]

Originally posted by LuckyStrike1
If a 28 year old racingcar stands a chance to a modern racingcar - then there is something seriously wrong.

Not there isn't! The R8 is constrained by modern rules. If Audi were to attempt to build a car today using safety regulations from the mid 70's Can-Am series the car would be so fast that it would be un-drivable. Think about it, in the 80's they were extracting up to 1400 hp out of 1.5 litre turbocharged grand prix engines, could you imagine what Audi could do today with 5.4 Liters!!! Not to mention basically unrestricted possibilities for the use of ground effect! Governing bodies tend to tigten up the rules to control speed in all forms of motor sport for safety reasons. Grand prix cars were hitting 200 miles per hour in the 1930's, using the most rudimentary tirer, virtually no crash protection and no limits on engine displacement or fuel chemistry. The 917 pushed some very loose rules to the absolute limit. It does not at all surprise me that a 28 year old car could be faster than a modern car, safety standards were far far far lower. This is just another, (interesting) case of apples and oranges.

[Ross Stonefeld]

The thing is, the Audi would destroy it in the corners. I bet a Porsche 911 is as fast in the turns as a 917. Unless you were on a drag stip, the Audi would win.

[Cociani]

Ross, how about Monza? Unmolested Hockenheim?

[Ross Stonefeld]

The thing is, whatever straight acceleration/top speed advantage the 917 would have, the R8 would neutralise by coming out of the chicane 20mph faster to begin with. You make up the most time in the slowest parts of the lap, and thats where the R8 would bury it. The r8 has some *serious* aerodynamics going on, like the entire nose area before the front wheels is a massive wing with a nose cone on it.


http://www.motorspor...es/sp00_024.htm


The R8 is a fascinating piece of machinery. Alboreto described it as an F1 car with enclosed wheels

[LuckyStrike1]

Originally posted by Cociani


Not there isn't! The R8 is constrained by modern rules. If Audi were to attempt to build a car today using safety regulations from the mid 70's Can-Am series the car would be so fast that it would be un-drivable. Think about it, in the 80's they were extracting up to 1400 hp out of 1.5 litre turbocharged grand prix engines, could you imagine what Audi could do today with 5.4 Liters!!! Not to mention basically unrestricted possibilities for the use of ground effect! Governing bodies tend to tigten up the rules to control speed in all forms of motor sport for safety reasons. Grand prix cars were hitting 200 miles per hour in the 1930's, using the most rudimentary tirer, virtually no crash protection and no limits on engine displacement or fuel chemistry. The 917 pushed some very loose rules to the absolute limit. It does not at all surprise me that a 28 year old car could be faster than a modern car, safety standards were far far far lower. This is just another, (interesting) case of apples and oranges.

Well in the turbo era of the 80's F1 cars has over 1000 BHP - up to 1400 in qualifying. But today cars are much faster than those cars despite approximately 200 BHP less on average.

So on top speed they might match but no way they match in roadholding around a circuit. And that's my point.

[blkirk]

Here are Donohue's qualifying times from the excellent book "Can-Am" by Pete Lyons.

Mosport 6/10/73 1:14.1, 119.468 mph (2.459 mile lap)
Road Atlanta 7/7/73 1:12.950, 124.42 mph (2.521 mile lap)
Watkins Glen 7/22/73 1:38.848, 122.989 mph
Mid-Ohio 8/12/73 1:20.335, 107.550 mph (2.400 mile lap)
Elkhart Lake 8/26/73 1:57.518, 122.534 mph
Edmonton 9/16/73 1:17.475, 117.421 mph
Laguna Seca 10/14/73 0:57.374, 119.217 mph (1.900 mile lap)
Riverside 10/28/73 1:10.290, 130.089 mph

Audi R8 times for 2001 from the ALMS web site

Mosport 8/19/01 1:08.222, 129.759 mph (2.459 mile lap)
Road Atlanta 10/03/01 1:10.917, 128.939 mph (2.540 mile lap)
Mid-Ohio 8/25/01 1:14.537, 109.057 mph (2.258 mile lap)
Laguna Seca 9/7/01 1:15.238, 107.084 mph (2.238 mile lap)

It looks like Laguna Seca and Mid-Ohio have changed quite a bit sometime in the last 30 years and Road Atlanta has had a minor face lift. That leaves us with Mosport which is either exactly the same or has been changed but happens to be exactly the same length. So, with one meager data point, it looks like the R8 is 8.6% faster than the 917/30K around Mosport. All the usual disclaimers about weather, tires, applicability to other tracks, fuel, track surface, etc. still apply.

[Ross Stonefeld]

Lola-Judds and Ferrari 333sp do I think 1:50's at Road America, CART is down to like 1:38. Atlantics 2:05 for pole (i think). I dont think Road America has changed in configuration, only pavement and safety.

[cjpani]

I believe most of us might want to take a peek at www.porsche917.com.ar
regards
cj

[AndreasNystrom]

There is a god!. Yesterday, i thought i was going to record a tv-show called Auto Mondial on the tv-channel "Avante". I missed Auto Mondial, but thought i could always record the program which was broadcasted after that, since Avante always shows something cool (almost only Airplane Cars, or Motorcycle documentrys).

Ok, so i pressed Rec, and saw it was a program about "John Wyer".. i thought i recognised the name, and after seeing a picture of him in the program, aswell as video-interviews, i thought i had see him before.. i leaved the tv, and comming back 40minutes later my heart almost stopped!.

THERE IT WAS!, A PORSCHE 917 AROUND LEMANS!!!!!!!!!!!. I almost cried
John Weyr as in Ford GT40 and Porsche 917!, that was the man!.

They showed the classical LeMans-laps, including a lap around LeMans in 64 or 65 (cant remember right now) in the GT40!!!. There was also interviews with the drivers (pedrigez and more) and footage from Monza (damn the 917 was FAST!) around SPA (where Rodrigez or was it Podrigez?) got his record-lap) they showed the fight between the Porsche 908 and the GT40 at lemans (last lap)
One driver (cant remember his name, it was something wierd) told about when he tested the GT40 around lemans for the first time, and he noticed wheelspin at the long straight, in topspeed, and he told Wyer about this, but he didnt believed him, and he also told Wyer that the car flexed at topspeed, so he could put his hand between the door?) and the roof i think it was.
He then said to Wyer that he should go around LeMans with him to see that it actually was like this, and at the long straight, he took his hand and showed how the body flexed and Wyer screamed to him to hold his hands on the wheel and concentrate on the driving
Then when you didnt expect it the front got of the car and Wyer got white in the face, and was terrified

Damn my english sucks, too bad i dont have a framegrabber card to my PC
then i could make a divx of it.

One more funny thing was Watkins Glen in the 917, where Rodrigez? was going to turn on the night-lights on the car, and accidently turned of the fuel instead, not realising what he had done until the car started to go rough on him, and he turned on the fuel pump again, and after that going faster than he had been for the rest of the laps


Avante is the best tv-channel i have ever seened. They only show this kinds of programs all time!.

[RiverRunner]

The Laguna Seca pic of the 917 is at the corkscrew,so that is the modern track,although it's been redone since then I'm sure.But that is none the less a telling time comparison and it appears that they would at least be able to stay on the same lap.
As to Ross' two observations,tyres and aero is worlds better nowadays unquestionably.
Interesting connection between two outstanding endurance racers none the less.
I I wasn't so lazy I'd do the numbers on them vs. a Nissan GTP as well.That was dominant car as well.

[Viss1]

I guess I'll have to admit that the 917 might only be a contender on a power track... like LeMans (the R8's stomping ground)!

Interestingly, Group 3 cars could qualify for Can-Am heats, and on a few occasions ended up racing with the big dogs. The Group 3 cars were quicker through the corners, but lost out overall. I'll have to go back and check the stats to see how much slower they were overall.

FWIW, Donahue was reluctant to attempt the 1975 record because he was in the middle of his difficult F1 season.

[bleakuzs]

Don't sell the Audi powerplant short, tractability and smoothness are also big keys to driving a car fast. Although I must admit, hearing a 917 at full song going down the back straight at Road Atlanta is the coolest thing out there.

I remember Michele Alboreto saying in an inteview at Sebring 2001 that the biggest difference between todays cars and the cars of yester year is in how fast you can shift the transmissions, consider the Audi shifts in .05 secong as opposed to .5 seconds, that's a lot of time in a racecar.

[bear]

I am still having trouble with the 400 liter gas tank in the 917.


mark