How turbo charging works!!! this should be good.
07-02-2010, 11:03 PM
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How turbo charging works!!! this should be good. OK...!!! Me and my pops just had a 4 hour fight about how a turbocharged motor works...He keeps relating it to a N/A motor and says IVE got it *** backwards. I say hes stupid and has it all kind of correct but is wrong about how the housing work on the turbo. and the intake manifold pressure
A couple things he says.....
-a turbo motor is always in vacuum....
-a turbo assists the intake air the motor naturally makes...
-the turbo headers do not have any pressure...
-and theres NO pressure in the intake...
-he also says that with out vaccume a motor can not run??? true...N/A
I started learning everything i could about how turbocharging works once i knew this was going to be my next route for my car... So here it goes, im going to explain to you guys how a turbo works and you then tell me if i have anything wrong...also if theres any websites on the operation of turbos include them. I think if ppl read this they can get a better understanding of how the turbo would effect there car.
Again correct me if im wrong cuz i need to prove this fat bastard wrong...proof is great too
here it goes...how i think it works!!!
First you start the motor. It then runs as a n/a motor would...It has vacuum so the downward pull of the motor sucks in the air...thus creating vacuum! It now takes a few seconds for the exhaust pressure to start spinning the turbo.
The turbo at this point is just spinning NOT having MUCH effect on the motor, if anything the motor might still be sucking "vacuum" air all the way to the turbo inlet.
Now as the throttle body opens your motor starts working harder making more exhaust. The valve opens, the piston starts its travel down the cylinder. With the intake valve open the piston starts taking in more air. As the valve closes the piston starts the return to the top compressing the air and fuel.....at top dead center BOOM!!! it explodes due to the spark plug pushing the piston back down "at the same point another cylinder is starting the rotation angin at the intake stroke". Now the piston is back on its way to the top but with the valve open.
With the valve open the exhaust gasses get forced into the turbo headers. At this point lets say around 2800 rpm the exhaust gasses start to get compressed into the headers pressurising. The exhaust gasses are now on there way to the exhaust housing of the turbo. In the exhaust housing of the turbo there is a little hole that leads into the turbo "the A/R size".
^^^now this, i look at as the same effect as a hose...let water come out the end and it falls to the ground...Now hold your finger over half of the hose and pressure kicks in and BAM pressure right? now the pressure is also created by the heat of the exhaust too so it really gets pushed through the fan on the exhaus side.
Now that turbo is spinning faster the compresser side of the turbo starts spinning faster compressing the air to a certin psi forcing it to the path of least resistance "the open intake valves" so now the intake is under pressure there is NO vacuum but positive pressure. The open intake valves take in 10psi of compressed air, more volume then atmospheric pressure, then closes. It is mixed with the correct ammount of fuel, then BAM you get a bigger boom sending the piston back down making more power. The faster everything turns and pumps the more the pressure builds after the exhaust valve closes causing your exhaust to pressure to go up. This in return helps a higher volume get forced into the exhaust housing spinning the turbo faster making more boost + hp...
Also after the exhaust housing fan blades you want as less pressure in the down pipe then the headers thus making that hose effect???
Am i wrong? Sorry this argument is driving me nuts and i just want to prove him wrong.
A couple things he says.....
-a turbo motor is always in vacuum....
-a turbo assists the intake air the motor naturally makes...
-the turbo headers do not have any pressure...
-and theres NO pressure in the intake...
-he also says that with out vaccume a motor can not run??? true...N/A
I started learning everything i could about how turbocharging works once i knew this was going to be my next route for my car... So here it goes, im going to explain to you guys how a turbo works and you then tell me if i have anything wrong...also if theres any websites on the operation of turbos include them. I think if ppl read this they can get a better understanding of how the turbo would effect there car.
Again correct me if im wrong cuz i need to prove this fat bastard wrong...proof is great too
here it goes...how i think it works!!!
First you start the motor. It then runs as a n/a motor would...It has vacuum so the downward pull of the motor sucks in the air...thus creating vacuum! It now takes a few seconds for the exhaust pressure to start spinning the turbo.
The turbo at this point is just spinning NOT having MUCH effect on the motor, if anything the motor might still be sucking "vacuum" air all the way to the turbo inlet.
Now as the throttle body opens your motor starts working harder making more exhaust. The valve opens, the piston starts its travel down the cylinder. With the intake valve open the piston starts taking in more air. As the valve closes the piston starts the return to the top compressing the air and fuel.....at top dead center BOOM!!! it explodes due to the spark plug pushing the piston back down "at the same point another cylinder is starting the rotation angin at the intake stroke". Now the piston is back on its way to the top but with the valve open.
With the valve open the exhaust gasses get forced into the turbo headers. At this point lets say around 2800 rpm the exhaust gasses start to get compressed into the headers pressurising. The exhaust gasses are now on there way to the exhaust housing of the turbo. In the exhaust housing of the turbo there is a little hole that leads into the turbo "the A/R size".
^^^now this, i look at as the same effect as a hose...let water come out the end and it falls to the ground...Now hold your finger over half of the hose and pressure kicks in and BAM pressure right? now the pressure is also created by the heat of the exhaust too so it really gets pushed through the fan on the exhaus side.
Now that turbo is spinning faster the compresser side of the turbo starts spinning faster compressing the air to a certin psi forcing it to the path of least resistance "the open intake valves" so now the intake is under pressure there is NO vacuum but positive pressure. The open intake valves take in 10psi of compressed air, more volume then atmospheric pressure, then closes. It is mixed with the correct ammount of fuel, then BAM you get a bigger boom sending the piston back down making more power. The faster everything turns and pumps the more the pressure builds after the exhaust valve closes causing your exhaust to pressure to go up. This in return helps a higher volume get forced into the exhaust housing spinning the turbo faster making more boost + hp...
Also after the exhaust housing fan blades you want as less pressure in the down pipe then the headers thus making that hose effect???
Am i wrong? Sorry this argument is driving me nuts and i just want to prove him wrong.
07-03-2010, 12:57 AM
#7
Your dad is wrong.
Specifically regarding the 5 points you posted that he made.
1. A turbo vehicle is only in vacuum while at idle or part throttle. Once the turbo has spooled enough to produce boost you will transition from seeing vacuum on your boost gauge, which is plumbed to your intake manifold, to seeing boost pressure.
2. This one he is sort of correct depending on what he means by "assists". So I will give him the benefit of the doubt here even though what he stated entirely much too simply put.
3. The turbo headers do have pressure....after all what spins the turbine? Turbines operate off of pressure differential to rotate. If there is no pressure differential across the turbine wheel then the turbine cannot spin. This is also why when you take a car that needs a T6 flanged turbo and slap a turbo on it with just a T3 flange and a small A/R turbine it creates huge amounts of backpressure in the exhaust pre-turbo.
4. Uuuum buy a boost gauge like Sparky said. Boost equals manifold pressure in/hg (inches of vacuum or mercury) equals vacuum.
5. I think he means like the rest of the vehicle like the brake booster in some cars that is assisted by manifold vacuum. However, when you get off of the gas then the engine also goes from a boost state back into a vacuum state, which will allow proper operation of the brake with a engine vacuum assisted brake booster. I will give him 1/4 credit for this one even though he really made his statement MUUUCH too general.
Soooo lets add this up. Out of 5 questions he sort of got 1.25 of them right, kind of. That is 25% correct which is being generous.... Your dad officially fails miserably at understanding forced induction and turbocharging. If he has any sort of technical institue certificates hanging on his wall please tell him to burn them.
Specifically regarding the 5 points you posted that he made.
1. A turbo vehicle is only in vacuum while at idle or part throttle. Once the turbo has spooled enough to produce boost you will transition from seeing vacuum on your boost gauge, which is plumbed to your intake manifold, to seeing boost pressure.
2. This one he is sort of correct depending on what he means by "assists". So I will give him the benefit of the doubt here even though what he stated entirely much too simply put.
3. The turbo headers do have pressure....after all what spins the turbine? Turbines operate off of pressure differential to rotate. If there is no pressure differential across the turbine wheel then the turbine cannot spin. This is also why when you take a car that needs a T6 flanged turbo and slap a turbo on it with just a T3 flange and a small A/R turbine it creates huge amounts of backpressure in the exhaust pre-turbo.
4. Uuuum buy a boost gauge like Sparky said. Boost equals manifold pressure in/hg (inches of vacuum or mercury) equals vacuum.
5. I think he means like the rest of the vehicle like the brake booster in some cars that is assisted by manifold vacuum. However, when you get off of the gas then the engine also goes from a boost state back into a vacuum state, which will allow proper operation of the brake with a engine vacuum assisted brake booster. I will give him 1/4 credit for this one even though he really made his statement MUUUCH too general.
Soooo lets add this up. Out of 5 questions he sort of got 1.25 of them right, kind of. That is 25% correct which is being generous.... Your dad officially fails miserably at understanding forced induction and turbocharging. If he has any sort of technical institue certificates hanging on his wall please tell him to burn them.