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I was driving home form Anger managment today and was thinking about anothe r post of mine. The Subject was air intercoolers and if it would be benifit or not. I decided that without a turbo or Super charger it would be worse off. Then I got to thinking of what the difference is between a turbo and a vacum. The only thing I could think of is that the amount of boost is regulated by the RPMs. Now I am not saying I am going to go and put a vaccum in my car Ijust thought I would throw the concept out there because the vacum would take less power from the motor to produce boost then a turbo would.
 

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Yes an intercooler is not beneficial unless you have hotter than ambient temp pressurized air that needs to be cooled.

On your new suggestion, you are talking about vacuum cleaner? that same concept has been around for a while - they are called 'electric superchargers'. You will be ridiculed if you bring it up. Maybe search on electric supercharger and check out the threads
 

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Dain bramaged
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there were some blokes that used a gas powered leaf blower on a civic and got intresting results.
 

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Discussion Starter #4
Like I said I am not going to strap on a vaccum to my car I just thought I would brain strom the concept get the juces flowwing you know. his si how all great ideas start.
 

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I hit **** with sticks!
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there were some blokes that used a gas powered leaf blower on a civic and got intresting results.
LMAO... thing is if you force air into an engine using anything, leaf blower, desk fan, or whatever, you will get results better than stock.

Creating a vacuum in the exhaust system might have an effect, but not as much as forced induction, such as a turbo or supercharger.
 

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LMAO... thing is if you force air into an engine using anything, leaf blower, desk fan, or whatever, you will get results better than stock.

Creating a vacuum in the exhaust system might have an effect, but not as much as forced induction, such as a turbo or supercharger.
Might cause a loss of performance, since the scavenging would be lost. Some back pressure is necessary unless the engine is pressure-fed.
 

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You can do it. But whether you have a 40-60hp electric motor driven by the alternator, or a conventional belt driven blower, or even an exhaust driven turbo, the fact is that part of the power it makes goes to driving it. In general, that power is around 40-60hp before an engine like the 3.5 is rendered into fragments of sharp, hot metal. (assuming a fairly efficient blower/turbo design)

An electric motor in that power range weighs a lot more than a simple belt drive, or all the ducting required for a turbo. And you would need an alternator that can produce 40-60hp to drive that electric motor, and that will weigh just as much as the 40-60hp electric motor.

Lighter, simpler, and a lot easier to maintain if you go with a traditional blower/turbo design. If you just want to go a 1/4 mile at a time, nitrous oxide would be the easiest of all.

And yes: without a device to pressurize the incoming air, an intercooler as they are currently designed would present a restriction to the airflow, and a net loss of performance.

Jim Snover

Yes an intercooler is not beneficial unless you have hotter than ambient temp pressurized air that needs to be cooled.

On your new suggestion, you are talking about vacuum cleaner? that same concept has been around for a while - they are called 'electric superchargers'. You will be ridiculed if you bring it up. Maybe search on electric supercharger and check out the threads
 

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You can do it. But whether you have a 40-60hp electric motor driven by the alternator, or a conventional belt driven blower, or even an exhaust driven turbo, the fact is that part of the power it makes goes to driving it. In general, that power is around 40-60hp before an engine like the 3.5 is rendered into fragments of sharp, hot metal. (assuming a fairly efficient blower/turbo design)

An electric motor in that power range weighs a lot more than a simple belt drive, or all the ducting required for a turbo. And you would need an alternator that can produce 40-60hp to drive that electric motor, and that will weigh just as much as the 40-60hp electric motor.

Lighter, simpler, and a lot easier to maintain if you go with a traditional blower/turbo design. If you just want to go a 1/4 mile at a time, nitrous oxide would be the easiest of all.

And yes: without a device to pressurize the incoming air, an intercooler as they are currently designed would present a restriction to the airflow, and a net loss of performance.

Jim Snover
I have to disagree on a couple points here, sorry.
Firstly, belt or electric driven forced induction is parasitic, yes, but turbo's are not. They use what is already being expelled by the combustion process, to create a hot pressurized air stream back to the intake.
An intercooler does exactly that, it cools the charge air, making it more dense. It's "basically" nothing more than another radiator for air instead of coolant.
They both work on the convection/heat exchange principle.
It may in fact restrict airflow to the rad., thus causing the car to run a little hotter, but it won't be a restriction to the intake system, turbo or not.
The sort of same thing a CIA does. Cooler air is more dense, thus being able to accept more fuel into the mixture, and ultimately the engine.
Turbo's are considered "free" horsepower as opposed to any other method of forced induction.
7000 HP top fuel cars require 1000 of that to spin the blower at the ratio they spin relative to the engine RPM. Net result of 6000 HP
7000 HP top fuel cars that would be Turbo'ed would suffer no parasitic loss, and only benefit by increased power.
Correctly built engines for the intended application of boost, will not result in fragments of hot sharp metal.
No, you can't "slap" on 30lbs. of forced boost to an otherwise stock engine, but neither can you "slap" on a 100 HP shot of nitrous to the same engine without risking failure.
Nitrous requires more fuel when in use, just like a blown or turbo'ed engine.
Saying it's easier and cheaper is a misnomer IMO, and just luring someone into engine failure from a lean condition if they don't understand, or are not educated on the "other" requirements needed to make it reliable.
 

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Where you are going wrong in your concept of turbos is that they run on "free" power. There is no free power. If you are compressing air, you are doing work, that work will require energy from the exhaust. If you take energy from the exhust, it creates back pressure. The engine has to pump harder to push against that back pressure than it would with a straight exhaust. That net loss is the power it takes to drive the turbo. If you could have the same forced air to the engine without having a turbo, say the blower is driven by another engine, that engine would make more power than the turbocharged engine for the same amount of boost.

Intercoolers do represent a restriction to airflow. any time you break up a large volume of air and run it through a series of smaller passages, your parasitic drag increases from the increase in surface area of the numerous small passages. There is no way around the increase in surface area, that is what a heat exchanger is all about. If you have a non-intercooled turbo system, and you install a an intercooler, you will see your net boost, in psi, drop. This is as a result of the restriction imposed by the intercooler. You will probably see your output increase, this is due to the charge temperature reduction. But with no other changes but the addition of an intercooler, you will see your boost drop.

Try to forget the idea of anything in an engine being free. Any gain is offset by a loss somewhere else. Add a turbo, and back pressure rises to drive the turbo. You still make more power because you are forcing more air through the engine, but that power is not free. Add an intercooler and boost pressure drops due to the restriction, even as horsepower rises due to the reduction in charge temperature. In fact, add an intercooler, and the back pressure rises even more as the turbo has to work harder to push the air through the intercooler.

Jim Snover

I have to disagree on a couple points here, sorry.
Firstly, belt or electric driven forced induction is parasitic, yes, but turbo's are not. They use what is already being expelled by the combustion process, to create a hot pressurized air stream back to the intake.
An intercooler does exactly that, it cools the charge air, making it more dense. It's "basically" nothing more than another radiator for air instead of coolant.
They both work on the convection/heat exchange principle.
It may in fact restrict airflow to the rad., thus causing the car to run a little hotter, but it won't be a restriction to the intake system, turbo or not.
The sort of same thing a CIA does. Cooler air is more dense, thus being able to accept more fuel into the mixture, and ultimately the engine.
Turbo's are considered "free" horsepower as opposed to any other method of forced induction.
7000 HP top fuel cars require 1000 of that to spin the blower at the ratio they spin relative to the engine RPM. Net result of 6000 HP
7000 HP top fuel cars that would be Turbo'ed would suffer no parasitic loss, and only benefit by increased power.
Correctly built engines for the intended application of boost, will not result in fragments of hot sharp metal.
No, you can't "slap" on 30lbs. of forced boost to an otherwise stock engine, but neither can you "slap" on a 100 HP shot of nitrous to the same engine without risking failure.
Nitrous requires more fuel when in use, just like a blown or turbo'ed engine.
Saying it's easier and cheaper is a misnomer IMO, and just luring someone into engine failure from a lean condition if they don't understand, or are not educated on the "other" requirements needed to make it reliable.
 
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