Topic: Need some advice on what to do

[oHIobellboy]

Turbocharger compresses the A/F mixture using exhaust gasses to spin the turbine

Interesting thread with video on both type of Superchargers. Centrifigal (vortec) and roots type (maggie) which are belt driven instead of exhaust gas driven.

[MyBigToy]

This is probably going to make those who already know laugh or cry...but here goes....Just to clarify (and probably scare some), a Centrifugal Supercharger is the same thing as Turbocharger correct?    The principle is basically the same, yes. OBB indicated the main difference - exhaust gas spooling the turbo vs. a belt driving the centrifugal. A turbo is considered basically "free" power because it doesn't rob horsepower like the accessory-driven belt on a supercharger does.

From what I gather, heatsoaking the engine/components is basically overheating?  Screw-type superchargers heat the air through friction as they "twist" (compress) the air into the engine. The smaller the pulley, the faster you turn the screws and the faster you heat up the incoming air charge. Hot air is less dense and therefore will make less power. There is a table in the engine programming that starts pulling timing above a certain IAT. Hot air also is more prone to knock, which again triggers the knock sensors to start pulling timing. I can tell a huge SOTP difference in the amount of power that my truck makes between 100* summertime temperatures and 20* winter temperatures. And I see the TVS units have a nice $ tag. Yes they do. Unfortunately, when you decide to play it doesn't come without its price.

K

[kklobe]

Interesting thread with video on both type of Superchargers. Centrifigal (vortec) and roots type (maggie) which are belt driven instead of exhaust gas driven.

As soon as I get to a computer connection that will let me see the link I'll check this out.  Crazy governmental computers....   big brothers everywhere!

[Main One]

No matter whether you use exhaust or a belt as the power source, or whether a roots or centrifigul configuration, laws of thermodynamics are at play which cause the intake air temperature to increase as it is compressed.  That said, each type of compression will also have its own peculiarities which may also contribute to temperature increases.

Beyond the issues identified by MBT caused by increased IATs, you also can run a slighter higher boost level for a given compression ratio or conversely a slightly higher compression ratio at a given boost level, (given a constant fuel octane level), with a lower IAT.  But more importantly, cooler air is denser air.

Thermodynamic laws state that for ideal gases (air is reseanably close to being an ideal gas) for a given amount of the gas, there is an interrelationship between pressure, volume, and temperature.  If we were to hold volume constant (say, the volume of a cylinder intake stroke) if the temperature is held constant, but we double the pressure, we double the amount of air.  Conversely though, if the pressure is the same, but double the air temperature, the amount of air going into the cylinder is cut in half.

To figure out how much effect a given air temperature has on the amount of air going in, the temperatures have to be converted to the Kelvin scale.  This is because unlike the Fahrenheit or Celcius scales, which have placed 0 degrees at rather arbitrary locations on their scale, 0 degrees Kelvin is ABSOLUTE 0, the coldest possible temperature.

You can find various unit conversion sites on the web to check these figures, or apply different input temperatures to the math I will offer here, but for instance, let's say your boost system is giving you a healthy amount of boost, but at IATs of 160 degrees F.  That is 344 degress kelvin.  If you ran an intercooler that got your IATs down to 80 degrees F, that would be 300 degrees kelvin.  The percentage increase in air that you would be putting into the engine if the boost was the same would be

(344-300)/344 = 13%

13% may not sound like much, but increasing the output of a 400 hp engine by 13% gives you a 452 hp engine.

So adding to the fact that you are getting in denser (more) air, with the benefits of reducing when you will see knocking, and the benefits identified by MBT (which are largely to control knocking), you see why IAT heating (and intercooler cooling) are so important in boosted applications.

[kklobe]

Beyond the issues identified by MBT caused by increased IATs, you also can run a slighter higher boost level for a given compression ratio or conversely a slightly higher compression ratio at a given boost level, (given a constant fuel octane level), with a lower IAT.  But more importantly, cooler air is denser air.

Thermodynamic laws state that for ideal gases (air is reasonably close to being an ideal gas) for a given amount of the gas, there is an interrelationship between pressure, volume, and temperature.  If we were to hold volume constant (say, the volume of a cylinder intake stroke) if the temperature is held constant, but we double the pressure, we double the amount of air.  Conversely though, if the pressure is the same, but double the air temperature, the amount of air going into the cylinder is cut in half.

To figure out how much effect a given air temperature has on the amount of air going in, the temperatures have to be converted to the Kelvin scale.  This is because unlike the Fahrenheit or Celcius scales, which have placed 0 degrees at rather arbitrary locations on their scale, 0 degrees Kelvin is ABSOLUTE 0, the coldest possible temperature.

You can find various unit conversion sites on the web to check these figures, or apply different input temperatures to the math I will offer here, but for instance, let's say your boost system is giving you a healthy amount of boost, but at IATs of 160 degrees F.  That is 344 degress kelvin.  If you ran an intercooler that got your IATs down to 80 degrees F, that would be 300 degrees kelvin.  The percentage increase in air that you would be putting into the engine if the boost was the same would be

I actually understand...lol

I have noticed different finished surfaces.  Is one surface better at dissipating heat compared to another, or is it all cosmetic?  Polished, satin....and so on.

[MyBigToy]

I actually understand...lol

I have noticed different finished surfaces.  Is one surface better at dissipating heat compared to another, or is it all cosmetic?  Polished, satin....and so on.

For all practical purposes the surface finish is cosmetic only. The exception would be for chrome plating as the chrome would actually hold heat in.

Generally speaking, the more surface area, the faster the heat dissipation - a satin finish theoretically dissipates heat better than polished because it is rougher and therefore has more surface area. That's why you see ribbed surfaces on aftermarket diecast transmission pans and oil pans.

[oHIobellboy]

Lots of good reading guys. 

[kklobe]

So after seven hours I have been able to watch about half of the above video.  I got to where they started to mount the drive belt and presto magic and crappy sat connections.....nothing .  I like the centrifugal systems but I'm still undecided if that will be the type of system I install.  Do either of the styles of systems make very much noise?  I know after I installed my cold air intake, I had at least twice the amount of engine noise.  After thinking about the way the intake is shaped, without the air box....I was able to understand the noise.  But this goes back to the "I have no idea about these again...lol.

Thanks,
Kevin

[MyBigToy]

The Magnacharger MP units make a pretty loud whine when you are under high boost. There's no additional noise when you're driving normally; there's a vacuum-actuated bypass valve that stays closed under low-load conditions. Compared to the Maggies I've got to say the centrifugals are much quieter; they make more of a whooshing noise like a turbo. I don't know about the TVS units as I've never been around one of them.

[kklobe]

So here is what I'm considering...http://www.summitracing.com/parts/VOR-4GL218-128SQ/  But with this unit, an intercooler will help improve performance through the summer correct?  I understand the hot air/cold air issues.  It's the same thing when we fly the medivac choppers.  You get more lift with cooler air...

I still think this is one of those "I should have someone else install" operations.  I am very mechanically literate, but never having attempted anything like this, I still don't know yet

If I don't go with the vortech unit then possibly:  http://www.superchargersonline.com/product_detail.asp?Sent=FREERIDE1@EMBARQMAIL.COM&ProductID=1470&s_emessage=

And as always fire away with any good, bad or ugly stories with either of these systems...

Thank,
Kevin