19 replies to this topic

[john aston]

Idly watching the Chateau Impney coverage on catch up TV  to get out of this infernal sun , my ears pricked up and my mind said ' come off  it ' . Because the custodian of the BRM V16 claimed that the beast had been timed at Silverstone  at 206 mph . Putting aside the fact that Bourne's finest folly would have struggled to do 200km/h s lot of the time because of its notorious tantrums, I really struggle to believe this. 

 

I am old enough to have seen 3 litre , thus 500bhp -ish ,F1 cars on the Hanger Straight in the circuit's original format and from memory, 180 mph was top whack . The BRM may have run less drag but would have exited Becketts and Chapel - 50 mph slower ? - than a slicks and wings 3 litre F1car , so how on earth did it overcome a slow corner exit and pull 20mph more ? And if it did, how come its brakes slowed it enough to get round Stowe ? 

 

I would be happy to be proved wrong but my fear is that an already overhyped car is being claimed to defy the laws of physics ...   

[Geoff E]

I've no idea how long Hangar Straight is, nor have I any idea how fast a car could get round Stowe but ...

with a deceleration of 32.2 ft/s/s, it would require about 360 yards to slow from 206 to 100 mph. I doubt such a deceleration would be sustainable anyway.

Such a long braking distance would shorten the distance available for acceleration after exiting Chapel, making the attainment of 206 mph even more difficult.

[Tim Murray]

In My Cars, My Career Stirling Moss noted that when he tested the BRM at Monza in early October 1951 he saw 11,400 rpm on the straight, which he believed equated to 184 mph. If that was the best it could do at Monza, there’s no way it could have achieved 200+ mph at Silverstone.

[Vitesse2]

I can believe Raymond Mays would have claimed it could do 200mph ...

[Henk Vasmel]

Racing cars don't have a "Top Speed" . It is a matter of gearing for the occasion, Air resistance (drag), these days traded off against downforce, and as indicated above, a straight to get to the highest revs in top, with enough space left to slow down again. For acceleration to reach there, not only max. power is important but also torque at lower revs to get there sooner (or many many gears).

If you want to you can make a racing car reach very high top speeds  , which will not allow them to do any serious lapping, because of low speeds in the corners.

Too many variables to instinctively say that I don't believe it .

On the other hand, with a claim like this, you have to be a bit more specific about details  . Or be seen as a retired fisherman , the biggest liars about achievements that I know of.

[Allan Lupton]

I can believe Raymond Mays would have claimed it could do 200mph ...

And if it wasn't Mays, Rivers-Fletcher might be the one who claimed it!

[Ray Bell]

I recall reading of some horrendous speeds in the Mays/Roberts book...

These were achieved at Albi.

[Tim Murray]

In that book Mays mentioned speeds of ‘somewhere around 190 plus’ on the two-mile straight at Albi. If Moss was doing 184 mph on the shorter straight at Monza in 1951, this estimate sounds not unreasonable, but this would again seem to suggest that 200+ mph on the much shorter Hangar Straight at Silverstone is pie in the sky.

[john aston]

Racing cars don't have a "Top Speed" . It is a matter of gearing for the occasion, Air resistance (drag), these days traded off against downforce, and as indicated above, a straight to get to the highest revs in top, with enough space left to slow down again. For acceleration to reach there, not only max. power is important but also torque at lower revs to get there sooner (or many many gears).

If you want to you can make a racing car reach very high top speeds  , which will not allow them to do any serious lapping, because of low speeds in the corners.

Too many variables to instinctively say that I don't believe it .

On the other hand, with a claim like this, you have to be a bit more specific about details  . Or be seen as a retired fisherman , the biggest liars about achievements that I know of.

 Of course- but whatever gearing you stuck in a BRM would it , could it , do 206mph at Silverstone  . Low cornering speed is critical in this debate as to get any chance of pulling its Vmax the BRM would have needed to exit Becketts Chapel as fast as possible .

 

 I can't be specific about details as all I am doing is quoting what the guy on the TV said . 

 

And good fishermen never lie , only the bad ones do . But I would say that ,woudn't I  ?

[Eric Dunsdon]

The way that Frolian Gonzalez drove the Mk1 V16 in the Formula Libre race at the 1952 British Grand Prix meeting he appeared to be doing at least 200mph round Copse Corner let alone Hanger Straight!.

[Charlieman]

Racing cars don't have a "Top Speed" . It is a matter of gearing for the occasion...

For any vehicle, CdA (drag) has a lower limit achieved by fairings etc and bhp has an upper limit, which together define maximum possible speed. I'd argue that some 1930s Formule Libre and GP class single seaters found their top speed at record setting events.

 

The Ferrari/Alfa Romeo Bimotore set a class record on a closed public road with an average speed just over 200 mph. Auto Union and Mercedes-Benz achieved other class records with modified GP cars before building specialist speed record cars.

 

I'd conclude that the maximum speed of the 1.5 litre BRM V16 on six miles of clear road would exceed 200 mph -- assuming that the horses turned up that day.

[Lee Nicolle]

Claimed speeds in motorsport are usually add 10-20% over what the physical speed could be.

Watch motorsport telecasts and that is so obvious. F1 car may do eg 200mph on a straight in qualifying, motor turned up to kill, 1 lap tyres, wing cranked down for less drag and 3 litres of fuel and say it does a 1.30 lap. Come raceday it is 20mph slower in a straightline, and 4 sec a lap slower.

And the same for Sports Cars, bikes, tintops,, anything!

And from what I have read about the V16 BRM they had so many niggles they would seldom if ever do the theoretical speed.

[Charlieman]

Claimed speeds in motorsport are usually add 10-20% over what the physical speed could be.

But we're going back to 1951, the first year that BRM managed to get off the grid at a Silverstone GP. There were no electrical timing devices on the start line straight or fastest stretch of circuit (so a step backwards from Brooklands) and no aerodynamic tweaks. The top speed achieved can be determined from top revs observed by the driver, gear ratios, tyre centrifugal expansion and tyre slip. With the help of Dunlop, BRM could make a pretty accurate guess at top speed -- and perhaps suggest a bit more to the supporters' association without telling a lie. 

 

Sometimes we forget that in 1951, Silverstone was considered a slow circuit. Fastest lap in 1951 was for Farina in an Alfa Romeo 159 at 99.99 mph.

[Ray Bell]

Originally posted by Tim Murray
In that book Mays mentioned speeds of ‘somewhere around 190 plus’ on the two-mile straight at Albi. If Moss was doing 184 mph on the shorter straight at Monza in 1951, this estimate sounds not unreasonable, but this would again seem to suggest that 200+ mph on the much shorter Hangar Straight at Silverstone is pie in the sky.

The Albi event was in 1953, and as Mays explains the reliability problems were by then solved. 585bhp at 11,800rpm and the cars were tearing tyres to shreds.

190+ is certainly a viable thought at that time, especially with Fangio determined to beat Ascari.

One wonders, by the way, whether the Silverstone suggested speed was back in the day, or was it recent?

[Doug Nye]

200mph?

 

The P15 V16?  As far as my researches found it was never even geared that high...

 

So sphericals... Indeed.  With knobs on...

 

 

DCN

[nmansellfan]

Hangar straight from the exit of Chapel to the entry at Stowe was roughly 775m, or in old money, just under 850 yards / just under half a mile.  Even the mid-eighties turbocharged F1 cars only just saw over 200mph braking into Stowe (anecdotally - I think there was only ever a speed trap at the finish line in the eighties).  Impressive a machine as the BRM V16 is, only if it was falling vertically over half a mile might it exceed 200mph in that distance

[Michael Ferner]

Even the mid-eighties turbocharged F1 cars only just saw over 200mph braking into Stowe (anecdotally - I think there was only ever a speed trap at the finish line in the eighties).

As chance would have it, I have in front of me the official timing reports of the 1987 and '88 races, and there was a speed trap on Hangar Straight. In 1987, Mansell and Senna did 204, Piquet 203 and the Ferraris 200 during final qualifying. Strangely, Nakajima was down amongst the naturally aspirated cars at 193 - weren't we always told he had preferential treatment from Honda? Next year, the fuel limited turbos maxed out at 196 (Ferrari) and 191 (Honda). Speeds at start/finish were generally lower by 15 (1987) to 20 mph (1988).

[Michael Ferner]

Strangely, Nakajima was down amongst the naturally aspirated cars at 193 - weren't we always told he had preferential treatment from Honda?

Scratch that - for one thing, Nakajima-san did 200 on the Friday, so he was probably trying another setup on Saturday, and to no avail for he failed to improve his times. Secondly, no normally aspirated car did more than 180 mph in either year - I saw "Benetton/Ford" next to Nakajima at 192, but forgot they still used a t/c V6 in '87!

[nmansellfan]

Great info, thanks Michael!

[Lee Nicolle]

Scratch that - for one thing, Nakajima-san did 200 on the Friday, so he was probably trying another setup on Saturday, and to no avail for he failed to improve his times. Secondly, no normally aspirated car did more than 180 mph in either year - I saw "Benetton/Ford" next to Nakajima at 192, but forgot they still used a t/c V6 in '87!

Trading straightline speed for cornering speed probably. Sometimes it works often it does not.

Though the old adage, gear the car for the corners not the straights.