18 replies to this topic

[cheapracer]

1/ I would like to find out some top speeds of Mk1 Lotus Cortina's in any guise (Group 5 etc) but of the day. I have 1 example of 138mph at Riverside 1967 - 138mph seems excessive but it is well known that RIR backstraight is downhill and often tailwind.

Any other examples known?

2/ Broad question, some hints as to some older obscenely powerful pre aero or little aero racing cars known. Can Am produced some but are there others maybe more obscure such as some hillclimb specials (Pikes Peak specials for example?). I am talking about more modern and drivable - not aeroplane engined 50's specials etc! - probably late 60's to early 80's, know of any F1 engined road car based specials for example?

For fun heres a very successful modern example, an E36 BMW with Judd V8 power.

http://www.georg-plasa.de/2/index.htm



And a MBenz 190E with V8 Judd

http://www.youtube.c...feature=related

[D-Type]

I'm not sure what period you really want to consider. I would have said that the twenties was the heyday of the aero-engined cars. However the New Zealand Lycoming Special dates to the fifties!

There was a class of racing in Britain in the sixties or seventies for 'Special saloons'. This essentially required athe cars to have the silhouette of a production car with anything underneath. Minis with various Cosworth 4-cylinder engines, V8 Cortinas, A DFV-pwered VW with a Formula 1 chassis, a 'Skoda' with a F5000 chassis etc.

[RS2000]

Re-Lotus Cortina, I guess it depends on what final drive was available then (or was homologated in the case of Gp2). I'm not sure whether the 3.54 for the "English" axle was around then. I think it first appeared later (std on Escort RS2000).
I believe the highest (numerically lowest) then for the homologated axle may have been the 3.7 (was this std on a Lotus Cortina?). I would guess a 4.1 was often used.
Theoretical figures from charts I have (for tyres that roughly equate to period racers but would not exactly align) give 136mph @ 8000rpm for a 3.7 and 142mph for a 3.54. Those figures would not have been reached in real life as aerodynamics (Cd in modern terminology) would come into play much earlier. I would be surprised if much over 120 was achievable.
With a smaller (and hence less aero-resistant) car (Escort) I found no overall advantage in going above 3.9 for sprints anywhere in UK, of which Goodwood is by far the fastest straight of any current sprint venue. In the case of both Cortina and Escort, the Mk2 versions have a worse Cd than the Mk1 versions.
Modern "historic saloon" gearing for Spa would give some indication but of course wouldn't be representative of running on the "in period" track layout.

[Nick Wa]

Like my friend RS2000 I doubt 138m.p.h. for a Lotus Cortina perhaps 128 unless it had an enormous excess of power. For an Escort MkI don't tell the fun police but 138 was on (self timed), at which point I decided I had exceeded both the legal limit and the tyres rating for long enough!
On second thoughts perhaps downhill as 118 happened uphill but that's another naughty story.

[cheapracer]

Originally posted by RS2000
Re-Lotus Cortina, I guess it depends on what final drive was available then (or was homologated in the case of Gp2). I'm not sure whether the 3.54 for the "English" axle was around then. I think it first appeared later (std on Escort RS2000).
I believe the highest (numerically lowest) then for the homologated axle may have been the 3.7 (was this std on a Lotus Cortina?). I would guess a 4.1 was often used.
Theoretical figures from charts I have (for tyres that roughly equate to period racers but would not exactly align) give 136mph @ 8000rpm for a 3.7 and 142mph for a 3.54. Those figures would not have been reached in real life as aerodynamics (Cd in modern terminology) would come into play much earlier. I would be surprised if much over 120 was achievable.
With a smaller (and hence less aero-resistant) car (Escort) I found no overall advantage in going above 3.9 for sprints anywhere in UK, of which Goodwood is by far the fastest straight of any current sprint venue. In the case of both Cortina and Escort, the Mk2 versions have a worse Cd than the Mk1 versions.
Modern "historic saloon" gearing for Spa would give some indication but of course wouldn't be representative of running on the "in period" track layout.

http://www.race-cars...090322571ss.htm

I find it hard to believe, thats why I want to find out for an upcoming simulation. They are narrow but 150hp, what 100lbs torque? and 4 gears getting 130+ mph, hmmmm......

[cheapracer]

Originally posted by D-Type
I'm not sure what period you really want to consider. There was a class of racing in Britain in the sixties or seventies for 'Special saloons'. This essentially required athe cars to have the silhouette of a production car with anything underneath. Minis with various Cosworth 4-cylinder engines, V8 Cortinas, A DFV-pwered VW with a Formula 1 chassis, a 'Skoda' with a F5000 chassis etc.

Yep! Any stand outs?

Frank Gardner's Corvair is one your lot just reminded me of.

[kayemod]

Originally posted by RS2000
I believe the highest (numerically lowest) then for the homologated axle may have been the 3.7 (was this std on a Lotus Cortina?). I would guess a 4.1 was often used.

Weren't all the production Mk 1 Lotus Cortinas fitted with a 3.9 ? Can't remember what the speedo used to read, but I'd guess at just under 110mph for a good standard car, it felt like it as well. Maybe slightly more if it came from the Lotus Press Fleet....

Addendum, the 3.9 was for the original A-bracket cars, later leaf sprung ones were slightly higher geared.

[FrankB]

Originally posted by D-Type
There was a class of racing in Britain in the sixties or seventies for 'Special saloons'. This essentially required athe cars to have the silhouette of a production car with anything underneath. Minis with various Cosworth 4-cylinder engines, V8 Cortinas, A DFV-pwered VW with a Formula 1 chassis, a 'Skoda' with a F5000 chassis etc.

... going OT, but wasn't it one of the stipulations that the engine had to be in the same location and driving the same wheels as the production car... thus the Beetle silhouette was ideal for an F1 style DFV installation. Wasn't it called the DFVW?

[GeoffE]

Originally posted by kayemod
Weren't all the production Mk 1 Lotus Cortinas fitted with a 3.9 ? Can't remember what the speedo used to read, but I'd guess at just under 110mph for a good standard car, it felt like it as well. Maybe slightly more if it came from the Lotus Press Fleet....

That seems about right - 1963 Road test - http://www.autocarma...a-Lotus/200097/

[RS2000]

Originally posted by cheapracer

http://www.race-cars...090322571ss.htm
I find it hard to believe, thats why I want to find out for an upcoming simulation. They are narrow but 150hp, what 100lbs torque? and 4 gears getting 130+ mph, hmmmm......

Well that link says it peaked at Riverside at 127mph, more or less what has been suggested above as a max top speed. "Texas World Speedway", where 138mph is claimed is the old College Station "superspeedway" oval isn't it? The (then top) NASCAR Grand National division went there in 78 or 79 and had problems I recall but that may have just been bumpiness. I guess a high banked superspeedway is the sort of place the ultimate max speed would be found. I'm no expert in running road race saloon cars on banking but compressing the suspension in the turns runing flat out might decrease the aero resistance and give a bit more speed? With high profile tyres I suppose 138 is not impossible - but largely irrelevant to what would be achieved on any proper road course? The BRM-prepared race engines in the Team Lotus Cortinas were probably giving a bit more than 150bhp by 1966. Ford works rally engines (also BRM-built) would have had 150? Hate to think what the ultimate twink gives in historics now...

[kayemod]

Originally posted by FrankB
... going OT, but wasn't it one of the stipulations that the engine had to be in the same location and driving the same wheels as the production car... thus the Beetle silhouette was ideal for an F1 style DFV installation. Wasn't it called the DFVW?

The DFVW I remember seeing was based on a VW 1500, not the Beetle.

[GeoffE]

Originally posted by kayemod


The DFVW I remember seeing was based on a VW 1500, not the Beetle.

http://www.racing70s...erman/vw411.htm

[kayemod]

Originally posted by GeoffE


http://www.racing70s...erman/vw411.htm

Yes that's the one, based on a VW411 (nee 1500), considering how many of those VWs must have been made, they are a remarkably uncommon sight on UK roads today, compared to Beetles of a similar age at any rate. They never came close to achieving cult status.

[David Birchall]

Not strictly relevent, but in the late sixties a friend had a Lotus Cortina with a Daimler V8. We took it down to Farnham to watch the stock car races and he was talked into entering it in the "Best Timed Lap by a Spectator". He never had to change out of second gear and won going away.... On the way back to Guildford up the Hogs Back road we registered 135 mph on the certainly optimistic speedo but it felt bloody fast!

[sterling49]

Originally posted by Nick Wa
For an Escort MkI don't tell the fun police but 138 was on (self timed), at which point I decided I had exceeded both the legal limit and the tyres rating for long enough!
On second thoughts perhaps downhill as 118 happened uphill but that's another naughty story.

Both achieved on a Bexley 12 car Nick?

[Ray Bell]

Originally posted by kayemod
Yes that's the one, based on a VW411 (nee 1500), considering how many of those VWs must have been made, they are a remarkably uncommon sight on UK roads today, compared to Beetles of a similar age at any rate. They never came close to achieving cult status.

411? 1500?

The 1500 was a Type 3, the 411 was a later (ugly) model that was different altogether.

The DFVW has previously been the subject of a number of posts here, with pictures IIRC. The Type 3 was better suited for this use than a beetle because of its longer wheelbase and probably better aerodynamic properties.

I thought, by the way, I might find something on speeds achieved at Bathurst (where they used to have a timed 'flying eighth' on Conrod Straight, in John Medley's book... however there were none that I could find. But Beechey's Chevy II Nova (327-powered, full house) did 150mph.

[Nick Wa]

Never did a 12 car!
Escort on M1 > A!(M) link achieved after 7 miles of foot to the floor, all steel engine, showing +8000 on a proper rev counter not the standard toy which had its needle pointing near vertical down.
Cortina uphill autobahn somewhere between Munich and Frankfurt.

[cheapracer]

Thanks for looking at Bathurst Ray, I also tried that. What about Silverstone Guys, surely theres a reading of what speeds 'under the bridge' somewhere?

Thanks RS2000, I did misread that article, 127mph, downhill, with a tailwind is more realistic.

I'll take your 411 and raise it with a 5litre Beetle! Defines 'ugly' quite well.

http://www.racing70s...hill-wilson.htm

We had Bryan Thompson do the same with a 1500 Fastback in Sports Sedan racing in Oz.

[dretceterini]

I have seen bugeye spites capable of 150 mph....but they had 200+ hp MGB motors stuffed into them...