How fast in a mile and a half?

[Tanguero]

I have the pleasure of being invited by the Jaguar Enthusiast Club to take part as a guest in their annual Woodbridge Speed trial on Saturday. Its a standing start with a speed trap a mile and a half down the runway.

The fastest speeds by Make/Model from previous years are;

Make/Model	Speed
SS 100	114.8
XK 120	132.3
XK 140	120.9
XK 150	134.2
C Type	145.2
D Type	177.3
Mk IX	106.0
E Type	161.0
Rob Beere E Type	184.0
S Type/Mk I/II	134.9
XJS	154.6
XJ	143.3
XJR	160.1
XK 8	143.2
XKR	162.4
XJR 15	172.2
XJ 220	199.72
Dodge Viper	199.65

There are no TVRs on the record sheet yet so hopefully I will make a respectable showing!

The other non Jag marques represented this year are a couple of Astons (a V8 and a Vantage), a GT40, an F 365 and Nadine Geary in that damned fast Viper!

Any guesses?

[dbv8]

169

[Nefarious]

dbv8 said:

169

I'd go a wee bit stronger, based on the speed set by the XJR (my family car). The XJ is quick, and does that "seemless surge" thing, but the Cerb at full chat will blow it into the weeds.

Also, based on my runway thing the other week, that everyone reckons was about 3/4 mile - my best terminal was 152mph, with a couple of 100 rpm in 4th still to go. To only put on another 17mph in the same distance again seems a bit pessimistic.

My guess - 176mph.

[peteA]

Tanguero said:

I have the pleasure of being invited by the Jaguar Enthusiast Club to take part as a guest in their annual Woodbridge Speed trial on Saturday. Its a standing start with a speed trap a mile and a half down the runway.

The fastest speeds by Make/Model from previous years are;

Make/Model	Speed
SS 100	114.8
XK 120	132.3
XK 140	120.9
XK 150	134.2
C Type	145.2
D Type	177.3
Mk IX	106.0
E Type	161.0
Rob Beere E Type	184.0
S Type/Mk I/II	134.9
XJS	154.6
XJ	143.3
XJR	160.1
XK 8	143.2
XKR	162.4
XJR 15	172.2
XJ 220	199.72
Dodge Viper	199.65

There are no TVRs on the record sheet yet so hopefully I will make a respectable showing!

The other non Jag marques represented this year are a couple of Astons (a V8 and a Vantage), a GT40, an F 365 and Nadine Geary in that damned fast Viper!

Any guesses?

Wonder what sort/spec Viper that was...?

[dbv8]

Do we know how healthy the 4.2 is?
Any recent power figures?

[Tanguero]

Last time it was on the dyno it peaked at 352bhp @ 6600rpm and 323FtLb @ 5200rpm and weighed in at 1235kg.

[Tanguero]

Nefarious said:

dbv8 said:

169

I'd go a wee bit stronger, based on the speed set by the XJR (my family car). The XJ is quick, and does that "seemless surge" thing, but the Cerb at full chat will blow it into the weeds.

Also, based on my runway thing the other week, that everyone reckons was about 3/4 mile - my best terminal was 152mph, with a couple of 100 rpm in 4th still to go. To only put on another 17mph in the same distance again seems a bit pessimistic.

My guess - 176mph.

It would be nice to beat the XJR 15
And nicer to beat the D Type

[Tanguero]

peteA said:

Wonder what sort/spec Viper that was...?

I believe it is supercharged with aquamist water injection and putting out about 650bhp!

[dbv8]

Tanguero said:

Last time it was on the dyno it peaked at 352bhp @ 6600rpm and 323FtLb @ 5200rpm and weighed in at 1235kg.

I stand and guess at 169.69

Is there a prize for the closest guess?
Little tip.... pump your tyres up high.
Bad for traction off the line but better for top end speed

[longbow]

I did this exact distance at Woodbridge with Straightliners last year. Those times you quote clearly aren't for standard cars - the Viper was highly modified (twin turbo or supercharged for sure).

My speeds were;



166mph at the mile and 172mph at the 1.5 mile point, both from a standing start. Acceleration profile (GPS logger) was;



Clearly, 0-100 in 10.5 secs is abysmal and reflects a fair degree of wheelspin through 1st (0-60 in 5.6 ). But mine is a 365hp car, so 172 terminal is fairly respectable for a standard 4.2 Cerbera I think. On the day I was faster than a standard ACR Viper and a remapped AMG SL55.

Netfarious said:

Also, based on my runway thing the other week, that everyone reckons was about 3/4 mile - my best terminal was 152mph, with a couple of 100 rpm in 4th still to go. To only put on another 17mph in the same distance again seems a bit pessimistic.

Yes, but don't forget that when you cross the mile point at 165+mph you're covering nearly 80m/s and will cover the last 0.5 mile in around 10 secs. By then acceleration has slowed down quite a bit (see graph above, 160 to 170 took 8 secs while 150 to 160 only took 5 secs - exponential increase) and you might only be putting on 1mph every 2 secs or so - hence the terminal doesn't increase by that much. I think to hit 180mph in a 4.2 Cerb you would need between 2 and 2.5 miles!

Edited by longbow on Thursday 15th July 19:22

[Rufus Roughcut]

longbow said:

I did this exact distance at Woodbridge with Straightliners last year.

I've posted this before ...any excuse to post it again, 4mins 28sec in

http://www.youtube.com/watch?v=MmUBfSVOUzM

Edited by Rufus Roughcut on Thursday 15th July 14:50

[BCA]

170ish mph, you've got a good launch technique and a strong car there.

As for the Viper, I believe you may be some way short of its actual power with a guess of 650bhp!!

Have fun.

[HarryW]

longbow said:

I did this exact distance at Woodbridge with Straightliners last year. Those times you quote clearly aren't for standard cars - the Viper was highly modified (twin turbo or supercharged for sure).

My speeds were;
...
166mph at the mile and 172mph at the 1.5 mile point, both from a standing start. Acceleration profile (GPS logger) was;
...
Clearly, 0-100 in 10.5 secs is abysmal and reflects a fair degree of wheelspin through 1st (0-60 in 4.6 ). But mine is a 365hp car, so 172 terminal is fairly respectable for a standard 4.2 Cerbera I think. On the day I was faster than a standard ACR Viper and a remapped AMG SL55.

....

Yes, but don't forget that when you cross the mile point at 165+mph you're covering nearly 80m/s and will cover the last 0.5 mile in around 10 secs. By then acceleration has slowed down quite a bit (see graph above, 160 to 170 took 8 secs while 150 to 160 only took 5 secs - exponential increase) and you might only be putting on 1mph every 2 secs or so - hence the terminal doesn't increase by that much. I think to hit 180mph in a 4.2 Cerb you would need between 2 and 2.5 miles!

Windsor are you doing it again this year, its sometime in August must get my name down. I was 161 when it was 3/4 mile a couple of years ago so hoping to try break through 180 this time. had a abysmal 1/4 go this weekend at an airfield, my times were frankly an embarrassing mess of wheels spin at 13.4@118. The good thing about long runs is that terminal speed is less affected by poor starting technique, suites me

[Byker28i]

longbow said:

I think to hit 180mph in a 4.2 Cerb you would need between 2 and 2.5 miles!

Probably about right for a standing start. Bruntingthorpe runway is listed as 2999m long, which is about 1.85m and I got a good runup onto the runway so had a head start. I think only Heathrow has a longer runway and we'd never get that

My guess is somewhere around the 170, hopefully beating most of the exotica.

Edited by Byker28i on Thursday 15th July 20:10

[Tanguero]

I just love that the fastest of the Jags apart from the XJ220 and the heavily modified Rob Beere one was a 1957 D Type!!!

Edited by Tanguero on Thursday 15th July 20:26

[julian64]

Not sure how used to these types of car you are, but most of those speeds are wildly optimistic for those cars. You must be dealing with some highly modifed cars. If you look on my profile you'll see a car which is practically a D-Type, same engine same chassis, but a better suspension.

It wouldn't see which way the Cerb went. It couldn't stay anywhere near the performance of the Cerb. Not even close. Its got about 250BHP absolute tops, and weighs fairly similar I would have thought.

But more than that, driving that car at above 100mph takes quite a lot of guts. The front goes very light over 100, and the original braking system is shocking. Much over 120 and you are averaging the steering. I just don't believe any standard car of that era could be driven to reach anywhere near the speeds recorded there by anyone other than balls out racing drivers. Or the cars aren't very original.

[dbv8]

Heres how my chim should perform after the engine rebuild and running nitrous.
It would be screaming at top speed, so may look into getting a longer diff.
click on the image twice to see in full detail

Edited by dbv8 on Friday 16th July 14:19

[Tanguero]

julian64 said:

Not sure how used to these types of car you are, but most of those speeds are wildly optimistic for those cars. You must be dealing with some highly modifed cars. If you look on my profile you'll see a car which is practically a D-Type, same engine same chassis, but a better suspension.

It wouldn't see which way the Cerb went. It couldn't stay anywhere near the performance of the Cerb. Not even close. Its got about 250BHP absolute tops, and weighs fairly similar I would have thought.

But more than that, driving that car at above 100mph takes quite a lot of guts. The front goes very light over 100, and the original braking system is shocking. Much over 120 and you are averaging the steering. I just don't believe any standard car of that era could be driven to reach anywhere near the speeds recorded there by anyone other than balls out racing drivers. Or the cars aren't very original.

A Chevvy powered Cobra? Not quite the same as an XK powered original D Type. The actual car that set that speed was placed in the top 6 in the 1957 Le Mans (4th I think). I take your point about the guts taken to drive it though! I wouldn't fancy it, and it was indeed a balls out racing driver that did that run.

Most of the cars listed are unmodified with the odd factory specials (Lister XJSs etc) and I am sure no one is being optimistic with the speed trap. I know that when we tried to get the XJ220 up to 200 we were gaffer taping every door shut and taking mirrors off, but other than that it was entirely unmodified.

I don't know about some of the other speeds, but I was personally there and witnessed those two runs.

Edited by Tanguero on Friday 16th July 14:24

[julian64]

Tanguero said:

julian64 said:

Not sure how used to these types of car you are, but most of those speeds are wildly optimistic for those cars. You must be dealing with some highly modifed cars. If you look on my profile you'll see a car which is practically a D-Type, same engine same chassis, but a better suspension.

It wouldn't see which way the Cerb went. It couldn't stay anywhere near the performance of the Cerb. Not even close. Its got about 250BHP absolute tops, and weighs fairly similar I would have thought.

But more than that, driving that car at above 100mph takes quite a lot of guts. The front goes very light over 100, and the original braking system is shocking. Much over 120 and you are averaging the steering. I just don't believe any standard car of that era could be driven to reach anywhere near the speeds recorded there by anyone other than balls out racing drivers. Or the cars aren't very original.

A Chevvy powered Cobra? Not quite the same as an XK powered original D Type. The actual car that set that speed was placed in the top 6 in the 1957 Le Mans (4th I think). I take your point about the guts taken to drive it though! I wouldn't fancy it, and it was indeed a balls out racing driver that did that run.

Most of the cars listed are unmodified with the odd factory specials (Lister XJSs etc) and I am sure no one is being optimistic with the speed trap. I know that when we tried to get the XJ220 up to 200 we were gaffer taping every door shut and taking mirrors off, but other than that it was entirely unmodified.

I don't know about some of the other speeds, but I was personally there and witnessed those two runs.

Edited by Tanguero on Friday 16th July 14:24

Err, no wait for the photo to load up in my profile

[Tanguero]

julian64 said:

Tanguero said:

julian64 said:

Not sure how used to these types of car you are, but most of those speeds are wildly optimistic for those cars. You must be dealing with some highly modifed cars. If you look on my profile you'll see a car which is practically a D-Type, same engine same chassis, but a better suspension.

It wouldn't see which way the Cerb went. It couldn't stay anywhere near the performance of the Cerb. Not even close. Its got about 250BHP absolute tops, and weighs fairly similar I would have thought.

But more than that, driving that car at above 100mph takes quite a lot of guts. The front goes very light over 100, and the original braking system is shocking. Much over 120 and you are averaging the steering. I just don't believe any standard car of that era could be driven to reach anywhere near the speeds recorded there by anyone other than balls out racing drivers. Or the cars aren't very original.

A Chevvy powered Cobra? Not quite the same as an XK powered original D Type. The actual car that set that speed was placed in the top 6 in the 1957 Le Mans (4th I think). I take your point about the guts taken to drive it though! I wouldn't fancy it, and it was indeed a balls out racing driver that did that run.

Most of the cars listed are unmodified with the odd factory specials (Lister XJSs etc) and I am sure no one is being optimistic with the speed trap. I know that when we tried to get the XJ220 up to 200 we were gaffer taping every door shut and taking mirrors off, but other than that it was entirely unmodified.

I don't know about some of the other speeds, but I was personally there and witnessed those two runs.

Edited by Tanguero on Friday 16th July 14:24

Err, no wait for the photo to load up in my profile

Ahhh - veerry nice!

Sorry for the misunderstanding, however my point stands - that I was there when the D Type did the 177mph run and I while obviously I can't be totaly certain - it was certainly being displayed as being in original Le Mans tune with original chassis and engine. I would guess the engine had been rebuilt several times so who knows what its exact spec was.