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      08-04-2009, 01:46 PM   #45
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That's why I'm asking... BTW what does not knowing what type of car have to do with spirited driving?? : )
Are you claiming your SSTT 135i that makes a more or less 300whp actually beat an ATOM in a straight line?

Unless you're talking about weaving through traffic llike the idiots in M5 and RS4, I must say whatever you're smoking is working perfectly.

Please, grab some sense of reallity.

That's like me saying I ate a ZR1 for breakfast.
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      08-04-2009, 07:28 PM   #46
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[shakes head]

If you can tune the 135i, then you're allowed to tune the Lotus. Running a smaller pulley, a Charliex tune, and a cup GT3 airbox on an Exige = kills most things.

You can tune the Lotus all you want and it's still not in the same catagory as an Atom. You go on and on about weight, but the Atom weighs HALF what an Exige does. HALF!

A 135i with an SSTT outrunning a Lotus is entirely possible. Outrunning an Atom (if he knew they were racing) isn't. How good it is on the track has exactly NOTHING to do with this story. I've outran half a dozen Lotus over the years, both in my GTO and the 135i but I'm not nearly delusional enough to think I can take an Atom. Even with its light weight an Exige is BARELY faster than a stock 135i in a drag race.
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      08-05-2009, 12:38 PM   #47
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Originally Posted by jeremyc74 View Post
You can tune the Lotus all you want and it's still not in the same catagory as an Atom. You go on and on about weight, but the Atom weighs HALF what an Exige does. HALF!

A 135i with an SSTT outrunning a Lotus is entirely possible. Outrunning an Atom (if he knew they were racing) isn't. How good it is on the track has exactly NOTHING to do with this story. I've outran half a dozen Lotus over the years, both in my GTO and the 135i but I'm not nearly delusional enough to think I can take an Atom. Even with its light weight an Exige is BARELY faster than a stock 135i in a drag race.
Of course.

The Atom is much faster than an Exige, an Exige is much faster than a 135i.

A tuned Atom is faster than a tuned Exige and a tuned Exige is faster than a tuned 135i.

An Atom is 1,000 lbs + change, an Exige is 1960 lbs (Elise weighs less), and a 135i is 3,400 lbs and change...

Nobody with the right number of chromosomes would ever drag race an Atom, Exige or Elise. All of these cars have open differentials (although LSD is an option on the Lotii) and independent suspensions, making them non-ideal for straight line drag racing. They are geared for linear acceleration and constant torque, rather than 1/4 mile drag times.

A tuned 135i (that goes limp on a track if you drive it right) will put out, say, 400whp.

A turbocharged Elise can put down 430 whp (aftermarket turbo, obviously)

A tuned Exige with stock supercharger and an aftermarket pulley can put down about 380 whp on stock internals. Not sure if there's a point of going above 300HP on an Atom, you don't need it.

135i, above pwr/wt = 0.116
Elise, above pwr/wt = 0.239
300 HP SC Atom = 0.285
Exige, above pwr/wt = 0.194

A stock Exige S220 dynos around 209 whp, while a stock 135i dynos at around 290, tops. 0.107 for Exige, 0.085 for the 135i. Even a stock elise at 170 whp (190 crank) that weighs ~1800 lbs has a 0.094 pwr/wt.

There's no point in comparing a 1000, 2000, and 3500 lb car.

Now an Atom vs. a Caterham would be interesting...

Drag racing a BMW is also pretty dumb, get a mustang with a solid rear axle and an LSD if you want to drag race. In the 135i's defense, its pedal layout is very nice and it provides good double clutch heel toe practice for formula cars I wish the throttle response was a little closer to NA+Cable
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      08-05-2009, 09:04 PM   #48
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Of course.

The Atom is much faster than an Exige, an Exige is much faster than a 135i.

NO IT IS NOT!!!

An Exige and a 135i turn about the same 1/4 mile times. I've handed an Exige its ass several times in both the 135i and the GTO I had before it. They're just not that fast in a straight line. The Atom will turn low 11 second 1/4 miles, which is well beyond either.


If you disagree, prove otherwise.
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      08-05-2009, 10:15 PM   #49
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NO IT IS NOT!!!

An Exige and a 135i turn about the same 1/4 mile times. I've handed an Exige its ass several times in both the 135i and the GTO I had before it. They're just not that fast in a straight line. The Atom will turn low 11 second 1/4 miles, which is well beyond either.


If you disagree, prove otherwise.
+1, even an Exige S 260 is barely faster (13.0) in the quarter than a stock 135i (13.3, both R&T times), and it takes a good bit more to get power out of the Lotus than the BMW, the only really successful changes to the Lotus I've seen involve ditching the supercharger for a turbo, so certainly not cheap. Even best case scenario with the Exige, it's shaped like a barn (like an Atom or Caterham), so over 120, it's pretty much dusted by most cars.

My buddy used to have a pre-S Exige that got worked over by tuned WRX's, STi's and Evo's on dry track days, not to mention many other cars. I lusted after an Elise/Exige before they came to the States, but they've proven to be a letdown for me, and I continue to lust after an R350 or R500 Caterham.

I see the guy with too few vowels point, the 1er is a terrible track car when compared to an Exige, or especially an Atom, or a Cayman or a lot of other things, but for a single hot lap, it isn't much less capable than a stock Exige, even if it is all sorts of out of shape in the process. The 1er is also cheaper to begin with and cheaper to tune to get noticeable results. My buddy's Exige had Ohlins suspension, different sways, pads and tires, and it was only slightly faster than a stock Exige. There's a lot more room for sizeable improvements on the 1er, and those changes also tend to be cheaper, even though it weighs 70% more.

Oddly enough, my buddy who had the Exige, and I looked at becoming the Atom importer before Brammo got them. I still think it's an interesting car, but would still prefer a Caterham.
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      08-06-2009, 06:30 AM   #50
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I see the guy with too few vowels point,




Coffee spit....
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      08-06-2009, 08:15 AM   #51
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When I see 1/4 mile, I stop reading... My last car was a 2007 Exige S and my current car a 2009 135i 6 speed w/ sports package, the two cars do not compare on a track in terms of handling. I'm talking differences of 7 seconds on a 1:20 lap time between the two cars, that's huge! Go to a track, and not an oval ring. Lighter cars smoke heavier cars, if they don't, add power and reduce weight and they will. This whole "heavier cars can be faster" thing is nonsense! Have you ever seen the inside of a racecar? Do you know anything about Collin Chapman? What about Lee Noble?

When I say "faster" and you say "quarter mile" it sounds like you only know how to stomp the accelerator and shift in a straight line. AutoX times say a lot too. When I got my Exige, I was amazed by the amount of downforce the car put down. At 40 mph, wiggling the steering wheel tossed me side to side, at 140 mph, it felt like it was on rails. Nothing but wind noise and downforce.

Quarter mile times include launches, which really don't apply to downshifting and flooring it on the highway, even. 60-120 times are a different story.



"Even best case scenario with the Exige, it's shaped like a barn (like an Atom or Caterham), so over 120, it's pretty much dusted by most cars."


The Exige is shaped like a Caterham? Like a barn? O...K... I can honestly say I have no clue what you're talking about there. Generally, you need a lot of horsepower to overcome the force of drag for even a small frontal cross-sectional area. Top speed doesn't have much to do with weight, weight determines how long it takes to get there. For every unit increase in horsepower, there is a cube root increase in top speed.

I posted the following on N54tech, recently:


Force of drag:

Fd = 0.5*rho*v^2*A*Cd

where rho is air density, v is velocity, A is cross sectional perpendicular area, and Cd is coefficient of drag (0.31 for e92 M3).

Power needed to overcome drag:

Pd = Fd * v

Let:

rho = 1.2kg/m^3 (~20C at sea level)
v = 89.4 m/s (200 mph)
A = 2.6 m^2 (frontal area of an M3)
Cd = 0.31 (for E92 M3)

Fd = 0.5*1.2Kg/m^3*(89.4m/s)^2*2.6*0.31
Fd = 3865.11 N (3.9E3 N w/ proper sigfigs)

Pd = 3865.11*89.4m/s
Pd = 345.541 kW (463 HP)
Pd = 460 HP (w/ sigfigs)

You need 460 WHP to maintain a speed of 200 mph at 68F at sea level in an E92 M3.


BTW: 200 MPH on GPS... 218 MPH on the speedometer (doesn't go that high).


The thing that really limits the Exige is top speed, because for top speed, you need horsepower. You can't reduce cross-sectional area and coefficient of drag enough. I almost purchased a Noble M400 with 600 WHP for $53,000, instead of my 135i. But after test driving one, I knew I'd lose my license of push the car too hard. It weighs 2300 lbs and puts out 600 WHP. I guarantee a 900 WHP vette can't touch a noble on a track.

Low curb weight is so much more important than horsepower. You can change horsepower, but it's nearly impossible to drop 1,500 lbs of weight from a car and keep it safe.

If I wanted to build an insane track car (for under 200K), I'd probably start with an Ultima GTR chassis and add a cosworth F1 engine that weighs 200 lbs and puts down 1200+ HP (even though they need constant rebuilds).

Say it with me: "our cars are luxury sports coupes, not track racecars"

Buy a miata with head work and have fun Light is beautiful. Nobody likes a fat chick.
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      08-06-2009, 12:36 PM   #52
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bunch of numbers
Look, I've seen your posts here, and in other parts of the forums, and you're mostly spot on, and I respect your inputs. But you're trying to make a mountain out of a mole hill here. My stance, and a few other, seemingly experienced ones, is that the Exige isn't the master track car that you've experienced, and as initially posted, a tuned 135i is likely faster in (silly, let's not really go there) street encounters.

I've driven them, and my M Coupe and Miatas, M3's, WRX's, STi's and a few other things on the track (with turns, gasp). I really do enjoy the Miata more than the others, even more than the Exige, but I'll give you that light is more entertaining. But it's not always faster, there is a difference.

I mentioned 1/4 mile times because it's enough distance to really get a feel for how fast a car is, not like 0-60 that tends to be influenced more by drive type, driver talent and tire selection. The aerodynamics of an Exige, with a Cd of 0.43, and a Caterham or Atom at around 0.55 or so are quite high when compared to almost any mass-produced car which tend to be in the 0.28 to 0.32 range, and this does mean that much more power will be needed both to achieve high top speeds, and to accelerate past 90 mph or so when aero drag starts to come into play.

I'll give you that a top notch, experienced racer will get a faster time out of a stock Exige S than a 135i on most any track, but a novice driver will benefit from the additional torque, more tractable power band and the stock understeer of the 135i (not that the Exige is free of understeer, at least in stock form, but there is a lot less, the 135i is awful with understeer). I can't really say which would be faster in the hands of a novice, but it wouldn't be night and day. I haven't tracked our 135i, as it just doesn't seem suited to it, and we don't have the car for that purpose.

To ask if I know who Colin Chapman is seems silly, but I'll tell you that I grew up watching Frankenheimer's Grand Prix, I've watched F1 since I was about five, I've lusted after a Caterham since I could drive, and I loved the Elise S1 when I worked in the EU and really wanted to get one when the S2 came out here, but for me, it's not the right car, and with my experience with my friend's Exige, I no longer want one. The Atom and Caterham are in an entirely different league, and still remain objects of desire for me, while the Lotus is no longer.
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      08-06-2009, 12:59 PM   #53
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Not sure if there's a point of going above 300HP on an Atom, you don't need it.
Tell that to Ariel



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Ariel announce the latest version of the Atom - the Ariel Atom 500, powered by a small V8 engine. With over 500bhp in a 500kilo package the Atom 500 will boast one of the highest power to weight ratios ever for a production car, ever. At over 1000bhp per tonne the Atom 500 will be the ultimate statement in performance and is destined to be made in a limited edition.

500-front-350w.jpgThe V8 powered Atom is the first of some exciting developments from Ariel due to be released though 2008 and builds on the growing reputation that the company has for putting the passion back into driving and producing cars that are fun to drive as well as fast both on and off the track.

The 500 started life as a one off special project with RS Developments in 2007 and features the Russell Savory designed 2.4 litre V8 engine coupled to a 6 speed sequential Sadev gearbox. Developing over 500bhp at 10,000rpm the supercharged engine features all alloy construction, 5 valves per cylinder and a dry sump. The gearbox will have flatshift capability, a paddle gearchange with manual override as well as launch and traction controls.

Recognisable by the twin rear intakes for intercoolers the Atom 500 will feature a unique colour scheme for chassis, wheels and bodywork combined with carbon fibre panels and carbon fibre aerofoils. Other features will include chromemoly aerofoil wishbones, integrated function steering wheel, Alcon 4 pot caliper brakes and Dymag magnesium wheels.

Said Simon Saunders, Director of Ariel, 'This is an interesting project for us and an experimental departure from what we normally produce. For a few customers the Atom 500 will be the ultimate expression of lightweight performance and represents the outer limits of what is achievable in a road registered car. We also use this sort of project to explore the possibilities of how we can improve our standard cars. The Honda engined production cars already combine all the elements that we want in an Atom and by pushing the envelope to these sorts of extremes we can further improve the breed'.

The Atom 500 will be produced in Somerset at the new Ariel factory with the first car available from Spring this year. Prices have not yet been finalised but Ariel's commitment to performance for value will ensure that the Atom 500 is competitive in cost as well as performance.

With the standard Atom 300 already achieving sub 3 second times to 60mph and sub 7 second times to 100mph, the 500 will take this one stage further with record breaking production car possibilities.

On a side note, I got a ride through some nice canyons in an Atom. It was actually the same guy who dressed as Vader for that infamous picture. It was... fast.
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      08-06-2009, 02:06 PM   #54
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Look, I've seen your posts here, and in other parts of the forums, and you're mostly spot on, and I respect your inputs. But you're trying to make a mountain out of a mole hill here. My stance, and a few other, seemingly experienced ones, is that the Exige isn't the master track car that you've experienced, and as initially posted, a tuned 135i is likely faster in (silly, let's not really go there) street encounters.

I've driven them, and my M Coupe and Miatas, M3's, WRX's, STi's and a few other things on the track (with turns, gasp). I really do enjoy the Miata more than the others, even more than the Exige, but I'll give you that light is more entertaining. But it's not always faster, there is a difference.

I mentioned 1/4 mile times because it's enough distance to really get a feel for how fast a car is, not like 0-60 that tends to be influenced more by drive type, driver talent and tire selection. The aerodynamics of an Exige, with a Cd of 0.43, and a Caterham or Atom at around 0.55 or so are quite high when compared to almost any mass-produced car which tend to be in the 0.28 to 0.32 range, and this does mean that much more power will be needed both to achieve high top speeds, and to accelerate past 90 mph or so when aero drag starts to come into play.

I'll give you that a top notch, experienced racer will get a faster time out of a stock Exige S than a 135i on most any track, but a novice driver will benefit from the additional torque, more tractable power band and the stock understeer of the 135i (not that the Exige is free of understeer, at least in stock form, but there is a lot less, the 135i is awful with understeer). I can't really say which would be faster in the hands of a novice, but it wouldn't be night and day. I haven't tracked our 135i, as it just doesn't seem suited to it, and we don't have the car for that purpose.

To ask if I know who Colin Chapman is seems silly, but I'll tell you that I grew up watching Frankenheimer's Grand Prix, I've watched F1 since I was about five, I've lusted after a Caterham since I could drive, and I loved the Elise S1 when I worked in the EU and really wanted to get one when the S2 came out here, but for me, it's not the right car, and with my experience with my friend's Exige, I no longer want one. The Atom and Caterham are in an entirely different league, and still remain objects of desire for me, while the Lotus is no longer.
The Exige is a lightweight, downforce making, tooth chipping, noisy, sometimes notchy, high-revving, sit on the floor track car. Much different than a 135i, and if I had to draw a line between track cars and road cars, it would be sitting on the opposite side of the room as the 135i. A WRX STi and an EVO would probably be marked in the middle of the line, maybe a little toward the track side. The Atom and Caterham are pretty much open wheel racers, so sure, they're different.

The Exige is not a master track car, but it is a pure blooded track car. I'm betting that a lot of that Cd is downforce, because when driven at its limits, the cornering is beastly on the Exige. Skidpad isn't a good representation of downforce.

I agree that a tuned 135i is likely faster than a stock Exige in a straight line, but to me, that doesn't matter much. You can tune anything, including a Lotus, and it's a popular thing to do in the Lotus community.

I'd be happy to stick to the Atom, since this thread is about a 135i allegedly killing one My most significant point is that higher curb weight makes it increasingly difficult for a car to overtake a lighter car on a track.

Anyway, Red Bread, I didn't mean to be patronizing, the frustration is directed entirely to the op, not you.



BTW: I'm aware of the 500 HP Atom, but seriously, there is no need for it! If I bought an Atom, and saw the 500 HP option... I just don't know what I'd do. I guess I'd pretty much have to buy it, even though it's excessive... or else I'd be a girly-man...
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      08-06-2009, 05:17 PM   #55
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When I see 1/4 mile, I stop reading....
Then you should have also stopped posting, because this entire thread was about something that would have been nothing more than a drag race.

No one here ever made the claim that a stock 135i was going to be faster around a road course than a Lotus, and you're completely wasting your time posting all that crap as if it has some bearing on the situation at hand.

In fact, I'd guess your entire purpose for taking this as far as you have was to attempt to impress people with the fact that you've owned a Lotus, or a bunch of numbers that mean nothing in the real world.

The fact of the matter is, if the car in question here had been a Lotus, and the OP had said he'd "killed it", it would be entirely possible. That's simply not the case with the Atom, and that was the entire point.
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      08-06-2009, 11:21 PM   #56
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Wish I could write up a cool kill story but...rulez are rulez
no way u killed it. not even a Porsche 9FF GT9 with its 987hp a lp640 or tuned z06 beats it in a 1/4 drag.
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      08-07-2009, 08:01 AM   #57
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Then you should have also stopped posting, because this entire thread was about something that would have been nothing more than a drag race.

...

In fact, I'd guess your entire purpose for taking this as far as you have was to attempt to impress people with the fact that you've owned a Lotus, or a bunch of numbers that mean nothing in the real world.
I didn't think drag races started at highway speeds... And of course, numbers and calculations mean NOTHING in the real world, not in science, not in engineering. Certainly not in things you care about, like road testing cars and designing the N54.

Let me dumb it down for you, since you obviously missed my point:

Light weight sports cars without LSDs are built to drive on tracks rather than drag strips. You might kill them on a drag strip, will not kill them on a highway pull (if they have a better pwr/weight and plenty of extra HP after they overcome drag), and definitely will not kill them on a track. Your car is heavy for no performance reasons.

And BTW: my Exige cost me less than my 135i, so I don't see how that would impress anybody. You obviously have some security issues... and if the "numbers" were over your head, they pertained to why horsepower almost directly determines top speed in cars, even though power/weight determines acceleration. Try thinking some time, I'm sure you're capable.

OP: PM me that kill story, "numbers" mean nothing in the real world, so I need to hear about how your car smoked one that weighs 1/3rd as much, with almost as much power.
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      08-07-2009, 08:34 AM   #58
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Light weight sports cars without LSDs are built to drive on tracks rather than drag strips. You might kill them on a drag strip, will not kill them on a highway pull (if they have a better pwr/weight and plenty of extra HP after they overcome drag), and definitely will not kill them on a track. Your car is heavy for no performance reasons.
.


All this stuff about being on a track has NOTHING to do with this post. It's a given that a Lotus is going to be faster around a track than a tuned 135i. It's also a given that an Atom is going to be faster than the Lotus, which goes back to my original statement that the two cars aren't in the same class.

The POINT of my statement earlier (and I'll repeat it for the 3rd time since you are totally ignoring it) is that it IS entirely possible for a 135i to outrun a Lotus. It is entirely impossible for it to outrun an Atom.

Nothing more, nothing less. Going on and on about power to weight and how the Lotus is a better track car is pointless....NO SHIT IT IS! No one ever said anything to the contrary. The FACT of the matter is that in the real world the Lotus isn't significantly faster than the 135i in a straight line and a "kill story" from the OP about a Lotus would be believable.
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      08-07-2009, 08:48 AM   #59
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All this stuff about being on a track has NOTHING to do with this post. It's a given that a Lotus is going to be faster around a track than a tuned 135i. It's also a given that an Atom is going to be faster than the Lotus, which goes back to my original statement that the two cars aren't in the same class.

The POINT of my statement earlier (and I'll repeat it for the 3rd time since you are totally ignoring it) is that it IS entirely possible for a 135i to outrun a Lotus. It is entirely impossible for it to outrun an Atom.

Nothing more, nothing less. Going on and on about power to weight and how the Lotus is a better track car is pointless....NO SHIT IT IS! No one ever said anything to the contrary. The FACT of the matter is that in the real world the Lotus isn't significantly faster than the 135i in a straight line and a "kill story" from the OP about a Lotus would be believable.
All of "this stuff" about being on a track? Power/weight, horsepower, coefficient of drag, and frontal cross-sectional area have EVERYTHING to do with how a car performs in a straight line once it's already up to speed. Everything. I wasn't talking about unsprung weight, wheel geometry, weight distribution, or skidpad.

You've taken a passing analogy about a car that I have experience with and have argued it to death. Let's talk about the Atom vs. the 135i. No way the 135i is beating it, ever. "Numbers" support that, and you seem to agree. You apparently didn't like the comparison I used to illustrate a point about weight reduction and power to weight.

I don't care how you categorize cars into a class system in your head.

FWIW: Ariel, Lotus, and Noble have been spotted in Norwich tea shops together sharing a basket of scones.
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      08-07-2009, 09:05 AM   #60
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All of "this stuff" about being on a track? Power/weight, horsepower, coefficient of drag, and frontal cross-sectional area have EVERYTHING to do with how a car performs in a straight line once it's already up to speed. Everything. .


Sure it does, but it's all pointless when we have REAL WORLD numbers to use to compare two cars, and we KNOW that a Lotus isn't much, if any, faster than a tuned 135i in a straight line. Bringing all that stuff into the discussion is just an attempt to cloud the issue.
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      08-07-2009, 10:01 AM   #61
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Originally Posted by jeremyc74 View Post
Sure it does, but it's all pointless when we have REAL WORLD numbers to use to compare two cars, and we KNOW that a Lotus isn't much, if any, faster than a tuned 135i in a straight line. Bringing all that stuff into the discussion is just an attempt to cloud the issue.
I'm not attempting to cloud anything, I like both cars... I wouldn't have purchased a 135i if it didn't kick ass. Modeling just happens to be what I do for a living, and I do it in my free time as a hobby.

In fact, I threw together a Matlab gui a while back to model straight line performance based on start speed and selected gear. You can even account for shift time (but not powershifting). I found that start speed can make a tremendous difference, so I'd say a lot of real world numbers can't accurately depict a specific situation. I included torque curves, gearing, drag, area, humidity, temperature (although I have yet to make temp and humidity affect a torque curve... gibbs free energy, ideal gas law, and a whole lot of physics didn't work so well).

Even though I had to benchmark everything and apply a few fudge factors for mechanical losses, it's better than going by numbers that don't tell the whole story. If you aren't breaking your wheels loose or limited by any other weird boundary conditions, modeling and calculation work very well. So much better than searching for an appropriate comparison to numbers that someone else logged. The things I went nuts over (temp, pressure, humidity) mattered so little compared to unknowns in other people's recorded times (like how they shift, how long they take, and how many people are in the car).

Peak horsepower means about as much as the peak wattage advertised on an amplifier. Things like 60-120 mph times are useful as table values (in my case for benchmarking), but only if you're going from 60-120...

This is a long way from a kill story, but I just wanted to explain that I'm not attempting to lose anybody in the numbers, rather, quick back of the envelope calculations can determine if someone is full of shit or not.
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      08-07-2009, 10:11 AM   #62
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Originally Posted by The Cthulhu View Post
...can determine if someone is full of shit or not.
I think we all knew that from the very first post, but it's still been fun discussing it.
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      08-07-2009, 10:42 AM   #63
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Quote:
Originally Posted by The Cthulhu View Post



-1


How about you save up your money and buy a weekend car. My 135i is nice and fast, and I love it... but it's no Lotus or Atom. Get real!



Quote:
Originally Posted by The Cthulhu View Post
I'm not attempting to cloud anything, I like both cars... I wouldn't have purchased a 135i if it didn't kick ass. Modeling just happens to be what I do for a living, and I do it in my free time as a hobby.
.

You can't model two unknowns, and that's why it's all pointless.

A - You don't know exactly how fast the 135i in the original post is. It's not stock, and you don't have any realistic power numbers for it. Even if you've got a chassis dyno run from that very car it's not enough infomation to accurately model it's performance on the road under variable weather conditions.

B - You don't know ANYTHING about the other car. In this case it's an Atom, and it's reasonable to assume that unless something was wrong with it, even a well modified 135i won't even come close.

We don't need models or theories to draw a reasonable conclusion about the outcome of a race between the two.

Now, you lumped the Lotus in with the Atom, and then took issue with the me saying the two weren't the same. The Lotus is certainly a much more track focused vehicle than the 135i is, but it's not even close the performance level of the Atom. Not by miles. The power to weight ratio is about double.

The power to weight ratio of a 135i vs a Lotus is close enough that winning a highway race against one isn't out of the realm of possibility, and it would be wrong to call BS on someone for saying they did. That's simply not the case when it comes to the Atom. It's HALF the weight of the Lotus with as much more more power. It's in a different league altogether, and you're not outrunning it with either of the other two cars.
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      08-07-2009, 11:22 AM   #64
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Originally Posted by jeremyc74 View Post
You can't model two unknowns, and that's why it's all pointless.

A - You don't know exactly how fast the 135i in the original post is. It's not stock, and you don't have any realistic power numbers for it. Even if you've got a chassis dyno run from that very car it's not enough infomation to accurately model it's performance on the road under variable weather conditions.

B - You don't know ANYTHING about the other car. In this case it's an Atom, and it's reasonable to assume that unless something was wrong with it, even a well modified 135i won't even come close.

We don't need models or theories to draw a reasonable conclusion about the outcome of a race between the two.

Now, you lumped the Lotus in with the Atom, and then took issue with the me saying the two weren't the same. The Lotus is certainly a much more track focused vehicle than the 135i is, but it's not even close the performance level of the Atom. Not by miles. The power to weight ratio is about double.

The power to weight ratio of a 135i vs a Lotus is close enough that winning a highway race against one isn't out of the realm of possibility, and it would be wrong to call BS on someone for saying they did. That's simply not the case when it comes to the Atom. It's HALF the weight of the Lotus with as much more more power. It's in a different league altogether, and you're not outrunning it with either of the other two cars.
First off, don't say "model two unknowns", that doesn't mean what you think it does. You can model a shitload of unknowns, that's what modeling is for. Second, you really like to argue... don't you. It's fine to make assumptions regarding the extent of modifications to a car, you're reaching so hard here. I approximated 400 WHP for a modded car, I don't care if you can push more out of it, it's a good high approximation.

We don't know anything about the Atom? If it was on fire or otherwise malfunctioning, you aren't killing it now, are you? You'd be putting it out of its misery... Assuming a realistic high end tune number for the 135i and stock figures for the atom is fine.

When you want to prove that someone is wrong, it's best to take them at their word. In this case, his car has 400 WHP and the Atom is bone stock. Both cars have to be racing or it wouldn't be a kill.

Why do you keep arguing the same thing over and over about what class to lump cars into? I think you just like to argue. We're agreeing on all these points about the Lotus being more of a track car, the Atom being much faster, and so on. You're just squabbling over the most trivial things.


The following statements would be very hard to argue against:

The 135i is a good daily driver.

Lightweight cars built for the track can be used as daily drivers, but make far better weekend cars.

If you cared a lot about having a very fast car, it would be less expensive to buy a used lightweight track car than it would to properly set up a 135i for any type of racing (a monster miata is cheap to buy and cheap to fix, a BMW isn't).



Wanna argue about something? Than stop agreeing with nearly everything I say. It seems like you're taking offense at the use of numerical data and the fact that I consider certain cars single purpose and built for the track. If your car is quiet and comfortable, it isn't a real racecar.

P.S. If you take a picture of someone's car on the road, you already lost. Even if it was some weird slow car you'd never seen before and you beat it in a race... you lost.
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      08-07-2009, 11:34 AM   #65
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Quote:
Originally Posted by The Cthulhu View Post
Wanna argue about something? Than stop agreeing with nearly everything I say. It seems like you're taking offense at the use of numerical data and the fact that I consider certain cars single purpose and built for the track. If your car is quiet and comfortable, it isn't a real racecar.

.

You keep going on and on and on and on about track cars but THEY WEREN'T ON A TRACK!!! I'm taking offense to the fact that you're totally ignoring the situation at hand so you can go off on some tangent in an attempt to demonstrate how smart you are. I never said a 135i was a race car. NEVER. So you can stop trying to suggest I did.

What I said was that a Lotus isn't in the same class as an Atom, and it isn't. PERIOD. You're not required to wear a helmet to drive it, or climb through a window to get into it. It's considerably slower in every measure, and the power to weight ration on the Atom is about double the Lotus. The Atom outruns some of the worlds most exotic vehicles that cost upwards of $1 Million, and the Lotus can be challenged by dozens of road going vehicles.

What I also said was that a tuned 135i COULD outrun a Lotus on the highway, and that hasn't been disproven either. The power to weigh ratio is close enough that it isn't impossible, or even unlikely. I've also done it personally several times, but that's another story altogether.

You say I'm the one who likes to argue, when you're the one going off on tangents that have nothing to do with the subject at hand, which is a race down the highway. All you have to do to end this argument is stop responding, because you're obviously not capable of taking my points and addressing them directly to prove otherwise.
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      08-07-2009, 11:54 AM   #66
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