89GTA2LV

Today, I was minding my own business driving home on the freeway when a late model black bmw 540i came up on me like a rocket going about 90, I was about 75.

I hit the gas and so did he. He kept up but did not gain to 110 and I was pulling away.

We both got off the freeway and raced from a stop light twice. Each time I was atleast 1 to 2 car lenths in front. I also noticed that he was driving a stick and mine is an automatic. At the end, he came up along side me and gave me a thumbs up. That was cool, I have not done anything like that in a long time.

I was really impressed with my GTA. ITs an 89 with a 350 stock. I only have a flowmaster catback. I ran the numbers on the 540 and was shocked, this is a BAD CAR

98- 2003 BMW 540i Sedan - Specs

BMW 540i Sedan
Curb weight, lb. 3803
Engine & electrical BMW 540i Sedan
Engine type DOHC 32-valve (4-cam) V-8 VANOS steplessly variable intake-valve timing
Bore x stroke, mm/in. 3.62 x 3.26/92.0 x 82.7
Displacement, cc/cu in. 4398 / 268
Compression ratio 10.0:1
Power @ rpm, hp 290 @ 5400
Torque @ rpm, lb-ft. 324 @ 3600
Performance Data BMW 540i Sedan
Acceleration, 0-60 mph , sec. BMW 540i Sedan 6.2
Sport Package 6.1
Top speed, mph BMW 540i Sedan 128
Sport Package 155

WOW, I guess these GTA's REALLY CAN MOVE!!

ThirdGenFire

I am more amazed that it can keep up on top end, we all know where our TPI are weakest. Congrats.

z28kindaguy

Great kill! That BMW has quite a few horses more than us stock and a little less torque, and you still took him.

nick418

good kill Beamers can push some serious numbers!

freestylzz

Whattaya mean? Like on a sales slip?

nick418

haha, HP TQ and SALES haha

pasky

safemode

iTrader: (1)

if he's got more torque and can put it on the ground (since both are about the same weight) , he'll beat him. Horsepower is a measure of efficiency, not power, it's a measure of energy produced not force. It means nothing when you're talking about how much power the engine produces, regardless of the outdated name. You can have an engine that makes 700 hp but if it makes less torque during a race with a 120hp motor the 120 will win every time.

That little rant being said, it's very surprising to see a stock 350 whoop on a technologically superior engine like that, even if it was 90 cu in smaller. You really dont find many BMW owners starting or participating in a race. I wonder if bmw makes an engine closer to the size of a 350 so we can see what all that expensive high tech machinery really adds up to.

good kill there. You'll be put in your place when you race a porsche, heh, that's not much fun unless you like watching rear bumbers.

89GTA2LV

I have raced porsches in the past. With my 88 formula tpi stick, I would make every 928 (including 928s4's) look like they were standing still off the line up until about 60 mph. 911's we easy too unless they were turbos. People think because they are Porsches they are really fast. Most are not. Especially if you wanted to get them in s turns. Most 911 drivers don't know how to drive 911 cars, they spin out and never catch up again.

iroc87matt

good kill

nidyanazo

Awd porsches are some of the bect handling cars around. With suspention upgrades they are even more amazing. It's hard to picture a porsche spinning out unless they are taking the turns WAY too fast...The driver must really suck. And in that case they bought the porsche for the wrong reason.

Gunny Highway

iTrader: (1)

Yep. A porsche and a vette are the only things I've ran into that can out-handle my car.

Marc 85Z28

iTrader: (3)

Took him on the top end too? There's a very good chance he couldn't drive worth anything (like most BMW guys). I've run them before with a good driver, and they're no slouch. Most car mags had them at low low 14s.

Those 0-60 times look like automatic equipped times, as the 6 speed cars would be nearly a half second quicker to 60 and through the quarter. They're about on par with an LT1 4th gen.

EDIT - About the Porsche rarely spinning out comment: Stop by an SCCA course or road race course sometime. REAL Porsche's are mid-engined, and have a tendency to oversteer. Oversteer + mid-engine + power = whoops!

rx7speed

might be with direct drive
but there are gears and stuff like that which affect the mount of torque that gets put to the ground

which is why at times a car with less torque can actually win

kinda like the F1 cars
only put out 250lbs/ft of torque
yet with all the drag and low torque they stil lcan crank out low 9's at around 170-180mph

rx7speed

I'm sure quite a few could out handle your car


like teh rx7.... rx7 owns ju

rx7speed

that\s more then oops


that ah well I thi......AAAAAAAAAAAHHHHHHHHHH SHHHHH!!!!!!!!!!!!!!!TTTTTTTTTTTT

anondude13

_

Gunny Highway

iTrader: (1)

I've seen like dozen RX-7 in my lifetime. I usually run into 8's, and they're never game.

Njspeed

HAHAH i spun my porsche 1987 944 (NON turbo) but your completely right its hard to spin them unless your taking a turn way to fast and your tires arent that good like a moron which i did. Live and learn wont happen again no harm done. Nice kill on the BMW btw there awsome cars

Der91Z

iTrader: (1)

Hard to believe that you beat it on top end too, considering i had a 97 540i and it would spank my 91z28 when it was stock. I got my 540i to a 14.2@99. But props to you since you said you beat it.

z28kindaguy

I agree. I think HP and torque are as important as the other.

nick418

my 1991 Z28 ran 14.3 at 97 mph bonestock.. Thats only .1 slower and 2mph slower then your 540.. I dont consider that a "Spank" Unless u had a 305 TPI Auto

freestylzz

Nah, I think what he's saying is the 540 past the 1/4 mile mark would pull away nicely from the 3rd gen, after all were talking about a German car built for the high speeds of the autobahn. I'm sure if the 540 was a lighter vehicle it would be a completely different story plus look out for the '04 + 540's

Der91Z

iTrader: (1)

My Z28 was a 305/5sp car, it did 14.8@94.

anondude13

Assuming you can gear a car any way you want, horsepower is all that matters.

rx7speed

you know that horsepower is nothing more then a math formula right?

Marc 85Z28

iTrader: (3)

Coming from a rotary guy!!!!!!

safemode

iTrader: (1)

Horsepower is a measure of heat energy produced. This heat energy is a potential energy the engine can use to actually do work. It doesn't technically have anything to do with how fast the car will go or how well it will perform race-wise. You can have an engine that produces 1000 hp it doesn't matter. Torque is what moves the wheels, torque is what accelerates you, torque is what will win you the race, not horse power. How much heat your engine produces is a measure of power but it's not a measure of force. Nobody ever blew their transmission or rearend from adding horsepower, torque is the only thing that can do that.

Nobody said horsepower isn't important to keep mind of, it tells you how well your engine is taking advantage of the fuel it's given, but it doesn't win you races. If you could decrease your horsepower but keep the same torque curve, you'd never notice a difference in performance. That wont ever be the case in reality, of course, since changing the efficiency of your engine changes how much torque it makes. If you decrease your torque however, but keep your horsepower curve, you'll notice a huge difference in performance, since you wont go anywhere nearly as fast, despite producing all that heat. How well your engine turns that heat into torque (ie, how much torque it produces) is all that really matters for winning a race.


Now that we're extremely off topic ... back to the regularly scheduled program.

rx7speed

horsepower has nothing to do with heat
you can't decrease your horsepower while keeping the same torque curve
you can't lower your torque curve without lowering your horsepower curve
horsepower has nothing to do with efficiency



not to be rude but honest man you should read up on this a little more bneing your info is WAY off.

in this case horsepower is math
horsepower = (torque x rpms)/5252
look at dyno graphs they ALWAYS cross at 5252 because horsepower is math

horsepower does help out with figuring things out though when dealing with gearing and such. being generally with higher horsepower motors you can tend to run a little more gear which would make for higher torque output at the wheels

rx7speed

low blow

foul on the domestic owner

anondude13

It's a math formula on the dyno, but if you were using an engine to produde raw energy, like heating water for example, it becomes a very real value. When most people talk about torque they mean horsepower at a low RPM, which can only be generated with large torque numbers at that RPM. Horsepower is what makes your car fast because a high revving motor can be in a low gear and have a higher torque multiplier at a given speed. (That's more torque at the wheels) Two identical cars with the same horsepower will perform the same, given ideal gearing in each vehicle, even if one is a torque monster and the other is a high revver. End of story.


I second that.

rx7speed

not quite end of story
there are quite a few things going on other then just peak numbers. area under the curve is quite important also and at times


even on using an engine to produce raw energy it is math based


hp is work over time.
hp = 3300lbs/ft of work in 1 minute or 550lbs/ft a second

only thing is they did a little math to switch the per second or minute to rotations per minute.

freestylzz

Check your math.

safemode

iTrader: (1)

You may be getting horsepower from a simple formula, but it seems you have no idea where that formula is derived from.

1. Horsepower does have a direct relationship to heat. Since it's directly equivilant to 746 watts. Watts are joules per second, Joules are a measurement of energy. Heat is energy. Sticking to non-metric measurement units when looking at formulas makes them very non-Intuitive, Converting them to the SI units shows you what they really are.

2. I said clear as day that you couldn't "in reality" (Note the in reality part here ,it's important) change your torque without changing your horsepower, and vice versa. They are linked as one is created by the other.

3. Since horsepower is indeed, a measurement of energy over time, it can be a measurement of efficency when you consider the fuel the engine is consuming and it's displacement.

4. Formulas are nifty things, you can substitute equivilant units and values for other ones and create new formulas. Formulas that contain the units you have available so you can work with the formula to derive a value that you are looking for or graph. Just because the one on the dyno doesn't have the correct units for heat or energy doesn't mean it can only be defined that way. I can define HP to be 746 watts or I can define it as 746 joules/second or 55lb/ft in 1 second. They're all the same.


In this case, you should read up. Nothing I said in my last post has been shown to be false.

Take two cars with different engines, one engine produces higher horsepower but it's torque curve is lower than the other car's. This is not outside of reality. Now when i say torque curve i'm not talking about a dyno, i just mean that across the rpm band, the one car is producing more torque than the other all the way through, yet is producing less horsepower. Those who say HP is the number to go by would say the higher hp car would win, but that goes against logic and physics. If your car has less force pushing it forward, how can it win a race? No matter how much energy the engine puts out ,if it's not being turned into a torsion force, it's not going to have any help for racing. That's my point, HP cannot be depended upon as a unit of "Can i win" because if the torque isn't there and above the other guy's for enough of the length of the race, you wont win. If i have more torque than someone else (and all else is generally equal) the entire length of the race I can guarantee you that I will win (granted traction) every time. I cannot guarantee that simply by having more horsepower the entire time.

In reality, torque is the force that makes you go, and it can be higher (across the rpm band) than another car while being produced on an engine putting out less hp than said "other car". Why you would still consider hp to be the best measurement of "who will win the race" knowing that is what is really being debated.

(edit, non-untuitive isn't a word. intuitive is better plus other spelling)

rx7speed

it works out for me
550 * 60 to convert it the the 550lbs/ft from seconds to min
comes to 33,000

oh oops just noticed I missed a 0 :-)

rx7speed

you did say in reality (my mistake)
I'm still trying to digest what you are saying though being I'm in a middle of a call at work with some ..... non-intuitive person so I'm a little slow right now :-)

but it seems like you are talking horsepower is how much heat the motor produces. can't other things create horsepower without heat....
don't ask me right now I'm still dealing with...
do I need to type in www.
no being it won't work if you do. just type in this xxxxx.com
it didn't work
well what did you type
www.xxxxx.com
remove the www and see how it goes
still doesn't work
well what did you type
www.xxxx.com
UGH!!!!!!!!!

anondude13

Because if engine A and engine B have the same horsepower and engine A produces less torque, engine A will by default be producing the horsepower at a higher RPM than engine B. Higher RPM means higher gear ratio for a given road speed. Since you multiply your crankshaft torque by the gear ratio and final drive ratio, this would give us THE SAME TORQUE TO THE WHEELS. Engine A will put the same torque to the wheels as engine B at the same road speed, given that engine A is taking advantage of its power with a lower gear, even if engine B is making more torque at the crank and is running at a lower RPM. Horsepower is a value that accounts for this fact, whereas torque does not. Ever wonder why Evo 8's come with 4.56's stock? How about why second gear is slower than first gear? The engine is making the same torque, I guess this defies physics???

safemode

iTrader: (1)

hp doesn't account for gear ratios, you're assumption that the car with more hp but less torque is able to run at higher rpms than the other car is what accounts for the ability for horsepower to be a marker. Your use of hp requires too many dependent variables to be really useful, the number of gears, the ratio etc. But you can get rid of all those dependent variables by just using the torque at the wheel.

I specifically disallowed higher rpms in one over the other by requiring that the hp and torque differences be across the entire rpm band they experience during the race.

There is a lot of requirements when using torque or hp as a measure of who will win a race, in the end you can probably use rear wheel hp as effectively as rear wheel torque but only because there are much fewer variables when you are at the tires between cars. Even then, both numbers can't simply be a maximum, they have to be representative of the area under the curve they experience during the race. The decision to use rear wheel torque over rear wheel hp is that torque makes more sense to guage acceleration than power does, since torque is a force and you can find acceleration by dividing it by mass, the one that accelerates faster wins. It just seems more logical that way, since that's what you're after, acceleration. Again though, i'm not allowing for higher revving engines because they change my statements just like weight differences would also change everyones, you'd need knowledge of the car to know if a car is capable of outrevving you and if it'll be able to utilize that within the time frame of the race.

I know i've jumped back and forth from talking about cars to engines and the hp/tq accompanied by both. too many topics going on at the same time here. In the end though, you can't blanket statement something is going to race better than the other based on hp or torque without knowing the assumptions the person is making stating that. You are correct in that crank hp can show which is going to win more than crank torque can if your assumptions are upheld. I'm correct if my assumptions are upheld. And when you're at the rear wheel, both units are are probably equally as useful at determining a winner since there is nothing left to be different really. I just find torque to be more correct becaues it's the force that is moving you, rather than use the measuerment of energy available to cause the force.

rx7speed

just wanted to note hp at the wheels should be the same as hp at the crank minus drivetrain loss

but

torque at the wheels is another story.
first you have gear multiplication and then drivetrain loss to take into account


so lets say a motor puts out 100hp an 100lbs/ft

at the wheels it might put out 88hp and 1000lbs/ft of torque

anyone care to explain other then you safemode

anondude13

If the gear multiplication is such that you're getting 10 times the torque at the wheels, the wheels will be rotating at 10 times less RPM than the crank. Let's keep drivetrain loss out of this to make things more simple. This keeps power constant, while torque can be modified. Which further proves the point that power is all that matters in theory.

Bigfoottpi11

I doubt he was really trying, I own both cars, a 350 TPI full bolt on car and a 540i. The Beemer is inbetween LT1 and LS1 territory just so you know.

Street Lethal

iTrader: (16)

Umm, nine year old thread... really lol?

no new tires

Who in the fack looks for, let alone READS a 10 year old thread.

Bigfoottpi11

Why ask why?

no new tires

Why ask why...about asking why.

Marc 85Z28

iTrader: (3)

No.

Stauf

iTrader: (2)

Now you all did it!! You brought it back to life. Its like "Pet Cemetery"

Out.

BADCAM70

I think the guy saying hp means nothing in a race and is a measurement for heat is really funny.

Bigfoottpi11

Yes it is, I own one and I also have owned a L98 350 TPI with bolt ons at the same time and raced both cars. I got left in the dust after second gear by the BMW.

penguinpanda0

You lose at physics... Dont they give you free college in sweden too? =P Just kidding around. Read about it though, its fascinating stuff!

http://en.wikipedia.org/wiki/Horsepower
I appreciated this necro-post, felt it was both entertaining and educational!