How much Thrust do the Exhaust Headers on a 2000 horsepower car generate ?

[St. Phatty]

I have a feeling the answer is staring me in the face.

You have to burn a certain amount of gas to generate that much horsepower.

It's not a fantasy question. There's a Vette that some guy put a 5000 hp engine in.

Anyway, just curious, if you could hold the exhaust pipe in your hand without burning yourself, how hard would it push ? Measured in Pounds.

Or, if you put the engine in a dynamometer that was mounted on a cart with really good bearings - a big if for a 3000 pound car with a heavy dyno - the whole thing would start moving because the exhaust is producing thrust.

But, how much thrust ?

If you attached it to a weight on a pulley, how much weight could it lift ?

I'm asking about the HUUUUGE amount of hot gas that is produced when the thing burns a gallon of gas every 1/100th of a second.

Another way to ask a similar question - how much gas does the car burn during the quarter mile run ?

 

[Creeperpark]

With that kind of super gear, we may never know the answer to that question.

 

[St. Phatty]

Enough thrust + air to blow up Marilyn's skirt ?

 

[exploziv]

It's easier to judge power generated by air intake rather than gas intake, cause it's guaranteed you aren't burning all the gas when you injecting that much.. But for sure you are burning all the gas that the available air can ignite.
I don't know the formulas, I am sure some time spent googling can give you the way to calculate it to a good ballpark figure.

 

[St. Phatty]

It's easier to judge power generated by air intake rather than gas intake, cause it's guaranteed you aren't burning all the gas when you injecting that much.. But for sure you are burning all the gas that the available air can ignite.
I don't know the formulas, I am sure some time spent googling can give you the way to calculate it to a good ballpark figure.

That's one of the advantages of Hydrogen as a fuel. There are no doubts about it mixing with Oxygen because, it's also a Gas.

One of the things that never entirely made sense to me is the Helmholtz equation that correlates air temperature to the velocity of air molecules, which is also connected to the speed of sound.

1000 feet per second is how fast the air molecules around us are moving, but it is random ... is the theory.

Anyway, for someone trying to light 8 cylinders of LOVE however many times a second, having your fuel mix thoroughly, QUICKLY, is very convenient.

 

[GOT_BUD?]

The NPK guys say that their bull horns generate about 450 lbs of downforce on each side when at WOT.

Steve Morris just put out a video talking about this very subject over on youtube. If you don't know who Steve Morris is, he built a 6 second Buick Roadmaster station wagon he takes on drag and drive events.

 

[Hiddenjems]

I have a feeling the answer is staring me in the face.

You have to burn a certain amount of gas to generate that much horsepower.

It's not a fantasy question. There's a Vette that some guy put a 5000 hp engine in.

Anyway, just curious, if you could hold the exhaust pipe in your hand without burning yourself, how hard would it push ? Measured in Pounds.

Or, if you put the engine in a dynamometer that was mounted on a cart with really good bearings - a big if for a 3000 pound car with a heavy dyno - the whole thing would start moving because the exhaust is producing thrust.

But, how much thrust ?

If you attached it to a weight on a pulley, how much weight could it lift ?

I'm asking about the HUUUUGE amount of hot gas that is produced when the thing burns a gallon of gas every 1/100th of a second.

Another way to ask a similar question - how much gas does the car burn during the quarter mile run ?

Is it a turbo car? If so a certain amount of exhaust energy is used to spin a turbine that spins a compressor feeding the engine. You can look up the turbine and compressor maps and figure it out.

The size and length of the pipes matter too. The gasses will take up less volume as they cool.

Another variable, exhaust valve timing. This determines how much extra energy is blown out the exhaust port instead of pushing down the piston.

The easiest way would be to do a velocity measurement and work backwards from there.

 

[hubcap]

Why?

Looking to attain low earth orbit? escape the surly bonds of gravity?



Sticking all that HP to the street in a useable manner is the real art.


-cap

 

[Dime]

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[Ca++]

It's about a ton of air/fuel coming out the back per hour. However it's velocity isn't particularly high, and thrust is an instantaneous measurement.
It wouldn't be a very good rocket. Exhaust systems are designed to flow, not hold pressure. There is no nozzle at the back.

edit: Sorry, the brain drain youtube was 4000bhp, this is 2000, so half a ton.
That guy drained me, he must of said his wastegate used to have an alloy pipe on it, 5 or 6 times in a row, before I reached out to forward 5 mins. Where he said his wastegate used to have an alloy pipe on it. He killed me right there. I am now dead. My soul depleted.

 

[Hiddenjems]

Why?

Looking to attain low earth orbit? escape the surly bonds of gravity?



Sticking all that HP to the street in a useable manner is the real art.


-cap

When racing on regular surfaces the power is usually fed in as speed increases with a timer based boost strategy in the Ecu map. There is also a driveshaft rpm sensor that compares either to a “perfect run” map or real-time data from a front wheel speed sensor for traction control based boost/timing.

 

[Ca++]

Traction control using a braking system offers good modulation. Reducing spin with braking, means you can keep the ignition events going, and so the turbo's on song. The reduction of power approach, lowers turbo rpm, so when the tyres hook up again, you may no longer be at full boost. Some of the turbo's used are so big, only interested in full power, that anti lag systems are a must. You really don't want to back off, unless you must.

I'm not keen on ABS or traction control tbh. They seem to get me in trouble. Perhaps with 2000bhp and a car that's trying to lift it's wheels, I might change my mind and look at rear wheel steering based on yore. So I don't need my front wheels on the ground to steer. Enough cars hit the wall, to show us that 'this is the way'

 

[Hiddenjems]

Traction control using a braking system offers good modulation. Reducing spin with braking, means you can keep the ignition events going, and so the turbo's on song. The reduction of power approach, lowers turbo rpm, so when the tyres hook up again, you may no longer be at full boost. Some of the turbo's used are so big, only interested in full power, that anti lag systems are a must. You really don't want to back off, unless you must.

I'm not keen on ABS or traction control tbh. They seem to get me in trouble. Perhaps with 2000bhp and a car that's trying to lift it's wheels, I might change my mind and look at rear wheel steering based on yore. So I don't need my front wheels on the ground to steer. Enough cars hit the wall, to show us that 'this is the way'

You aren’t knocking 1000hp off with the brakes. Loading the engine up like that would likely increase boost too, unless you’re about tapping out the turbo.


When you’re in a 1,000+ hp car breaking traction under full acceleration feels like hitting a wall. You just stop accelerating instantly is the sensation.


This stuff is what I did before I became a full time farmer lol.

 

[exploziv]

When you’re in a 1,000+ hp car breaking traction under full acceleration feels like hitting a wall. You just stop accelerating instantly is the sensation.

Sometimes, you just lose it and really hit an wall.
Can be scary even in an 300 hp car.

 

[Ca++]

You aren’t knocking 1000hp off with the brakes. Loading the engine up like that would likely increase boost too, unless you’re about tapping out the turbo.


When you’re in a 1,000+ hp car breaking traction under full acceleration feels like hitting a wall. You just stop accelerating instantly is the sensation.


This stuff is what I did before I became a full time farmer lol.

You shouldn't ever be using 1000bhp too much. That sounds more like farm machinery than finely honed electronics. Which is pretty much what we see down the strip here to.

Traction control is a combination of brake effort and power reduction. Over what should of been mapped out properly.

I mapped my car, after turbocharging it. It's standard practice in daily drivers to have different maps for different gears, that won't apply heaps too much, or let you veer off by taking the steering out of your hands through using motion sensing.

Power is nothing without control. However, fitting brake disks costs double in weight. They need sending down the track, and spinning in circles. I think that is probably why traction control is largely ignored.

Edit: Though not a top fuel example, it's interesting to watch a Tesla drive down like it's the most boring thing in the world. While cars around them make such a fuss.