Mr Mackey
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| posted on 27/4/14 at 05:09 PM |
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I think I need to go in a cec as it's been a while since I've had the pleasure.the zx10 just didn't cut the mustard I'm
afraid.if I'm spending my hard earned I need to be 100% happy and if I had the zx10 bec in be hiding from my mate in the Subaru 
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daniel mason
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| posted on 27/4/14 at 05:38 PM |
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ive had powerful imprezas and evos and non of them got off the line like my radical can! although I do run softer tyres,the performance is worlds
apart.the radical is in a different league.
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Sam_68
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| posted on 27/4/14 at 05:58 PM |
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quote:
Originally posted by Mr Mackey
I think I need to go in a cec...
You also probably:
a) Need to stop thinking in terms of 0-60 times. They don't even begin to tell the whole story.
b Consider 'full bodied' cars like the Sylva Phoenix and J15, or the Eclipse. Even with a decent car engine, the barn-door aerodynamics of
a traditional 'Seven' start to take their toll on acceleration once you get over 60-70 mph.
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daniel mason
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| posted on 27/4/14 at 06:12 PM |
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there was a 'brick shaped' westy at Aintree crossing the finishing line at over 140mph yesterday! not too shabby
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Sam_68
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| posted on 27/4/14 at 06:46 PM |
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quote:
Originally posted by daniel mason
there was a 'brick shaped' westy at Aintree crossing the finishing line at over 140mph yesterday! not too shabby
Yes, but with how much power?
Somewhat more than half a century ago, the car that the original Lotus Seven was based on (the Eleven, which had a properly streamlined bodyshell, of
course) set a World Record averaging 140mph over 100 miles. Fastest lap (not peak speed, mark you... lap) was over 145mph.
It had an 1100cc SOHC, 8-valve engine with somewhere between 85bhp and 95bhp.
So much for progress?
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Sam_68
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| posted on 27/4/14 at 07:31 PM |
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Just to add: I remembered that I actually did an empirical analysis of the comparative power requirements for a BEC vs. CEC Westfield SEi some time
ago.
I've just dug out the spreadsheet and plugged in the relevant numbers. For comparison, it says that for a Westfield to achieve a peak speed
similar to the (streamlined) circa 90bhp Eleven would take approximately 262bhp (assuming 15% transmission loss). So whatever was running at Aintree
must have had comfortably more than that, to be capable of accelerating to 140mph in the relatively short distance.*
In other words, a properly streamlined bodyshell (well, properly by the standards of 1957!) could give an advantage equivalent to about 170bhp.
In BEC terms, that's a second engine's worth...
* edited to add:
Except that according to the results HERE, it was
134mph terminal speed, not 140mph (I assume it's John Hoyle's results you're talking about?). Due to the exponential nature of aero
drag, it makes a big difference. 134mph would only absorb about 205bhp, again assuming 15% transmission loss. The calculated power requirements vs.
the Eleven still hold, however.
[Edited on 27/4/14 by Sam_68]
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daniel mason
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| posted on 27/4/14 at 07:52 PM |
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depends what bec you refer too?
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Sam_68
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| posted on 27/4/14 at 08:05 PM |
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quote:
Originally posted by daniel mason
depends what bec you refer too?
One with about 170bhp. Obviously. 
Pretty much equivalent to a Fireblade's worth of extra drag from the Seven's (absence of) aerodynamics, if you want to be specific!
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jwhatley
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| posted on 27/4/14 at 08:10 PM |
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Pervious owner of mine showed me a slip from some speed trial he had been to.
3.1 to 60, 6.6 to 100...
So I can't see a zx10 engined car doing it in 3.... Unless he has a silly diff ratio and can change gear like the wind!!
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Mr Mackey
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| posted on 27/4/14 at 08:11 PM |
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It does have a bike gearbox in I think.
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jwhatley
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| posted on 27/4/14 at 08:15 PM |
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So does mine, as will all other BEC's.
More likely to be 4-5 sec.
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daniel mason
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| posted on 27/4/14 at 08:16 PM |
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wikipedia?
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Mr Mackey
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| posted on 27/4/14 at 08:16 PM |
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I'm glad all the owners on here have been honest.i knew it wasn't as quick as my mate was saying.
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jwhatley
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| posted on 27/4/14 at 08:19 PM |
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quote:
Originally posted by daniel mason
wikipedia?
What?
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Mark Allanson
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| posted on 27/4/14 at 08:20 PM |
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Like I said to a work colleague recently, the 0-60 times are totally irrelevant, that is only the fist 5 seconds of any journey.
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
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daniel mason
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| posted on 27/4/14 at 08:21 PM |
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not refered to you mr whately! it was the other blurb on the thread
[Edited on 27/4/14 by daniel mason]
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jwhatley
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| posted on 27/4/14 at 08:23 PM |
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First 5? No.... The first 3!
But your right, totally irrelevant. It's good for pub talk and that's about it.
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daniel mason
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| posted on 27/4/14 at 08:35 PM |
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also I was referring to mr hodder not mr hoyle.
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jeffw
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| posted on 27/4/14 at 08:36 PM |
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quote:
Originally posted by daniel mason
there was a 'brick shaped' westy at Aintree crossing the finishing line at over 140mph yesterday! not too shabby
If you are talking about Gary Bunn (?) it was 137 MPH and his car has a supercharged Honda Type-R engine in it (BIG horsepower). Mr Hodder was double
driving this car.
[Edited on 27/4/14 by jeffw]
[Edited on 27/4/14 by jeffw]
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daniel mason
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| posted on 27/4/14 at 08:55 PM |
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the clock at Aintree was incorrect, the data logger said different. and mr hodder was 2nd ftd!
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Sam_68
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| posted on 27/4/14 at 08:58 PM |
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quote:
Originally posted by daniel mason
wikipedia?
quote:
Originally posted by daniel mason
not refered to you mr whately! it was the other blurb on the thread
If you're asking about my power analysis, then no... I used as many sources as I could find for accurately tested top speeds on the Westfield
(none of which was Wikipedia, some of which were my own), then used them to calculate and cross-reference a CdA. As I recall, there was a pleasingly
high degree of correlation between all the results, so I was happy that the CdA figure I arrived at was pretty accurate.
Rolling resistance and transmission losses are pretty typical for all cars, and from there the calculations are relatively straightforward.
Source for information on the Lotus Eleven's record attempt at Monza was Dennis Ortenburger's definitive book on the car.
HTH
quote:
Originally posted by daniel mason
also I was referring to mr hodder not mr hoyle.
Ah, OK. Still only 134mph, not 140, according to the results, though? But Garry Bunn came closer, at 137mph.
... Whatever. My original assessment still holds: they'd have all needed comfortably in excess of the power required for their terminal speed,
in order to accelerate to that figure in such a short distance. And the power requirements for these sorts of speeds still demonstrate very
graphically how inefficient the aero is on a Seven, compared to its full-bodyshell, streamlined cousin.
I've done a GPS verified 147mph in a 197bhp Skoda Estate, FFS (for which the manufacturer claims 149mph... I was robbed.  ). The
same power would barely see you past 130mph in a Seven! Aerodynamically, they're a bad joke.
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daniel mason
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| posted on 27/4/14 at 09:12 PM |
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if you cared to read and listen instead of talk,youd see the clock was wrong and the data logger was not. unless the driver was lying?
anyway unless you had a 90bhp aero car and a 260bhp 7 on the same track with the same tyres with the same driver on the same day its difficult to get
a realistic figure using a calculator and a pencil.
in the real world (competitive motorsport) a bec 7 can be a match for many high powered machinery,even on high speed circuits, although on a drag
strip maybe a drag car would be more suited
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bi22le
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| posted on 27/4/14 at 09:16 PM |
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Going back to the op and advice for him.
I would say that you have probably seen enough evidence to tell you that these cars are not straight line machines.
How ever if you are looking for fun b Road driving or a track day car that will be one of the quickest cars at any day then a kit car is the thing for
you.
I brought mine for these two reasons. If I wanted b Road enjoyment I would of got an classic car with a soft top and if wanted balls out track time I
would of got a bike.
Track days ARE the best thing since sliced bread, until I get a supercharger that is!
Please read my ring story:
http://www.locostbuilders.co.uk/forum/13/viewthread.php?tid=139152&page=1
Me doing a sub 56sec lap around Brands Indy. I need a geo set up! http://www.youtube.com/watch?v=EHksfvIGB3I
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Sam_68
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| posted on 27/4/14 at 09:16 PM |
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quote:
Originally posted by daniel mason
the clock at Aintree was incorrect, the data logger said different.
Really? An on-board datalogger (using notoriously inaccurate accelerometers and maybe GPS that can place the car to +/- the length of a double decker
bus) is more accurate than RAC-verified optical timing? OK, if you insist...
It's irrelevant, really, though.
Whatever top speed was achieved - be it 134mph, 137mph, 140mph, or Mach 1.2 on the datalogger, the fact remains that it will have taken a f**k
of a lot of power to get there, and they'd have had the potential to go a f**k of a lot faster if the same horsepower had been installed in a
car with half-decent aerodynamics.
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SausageArm
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| posted on 27/4/14 at 09:37 PM |
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Even with the ZX10R turbo engine in my Mac 1 Worx, first gear is a bit too tall to get brilliant 0-60 times, once over about 20mph it's brutal
right the way to the limiter in 6th!
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