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Discussion Starter #1
i don't know much about supercharger

what are the pros and cons of a supercharger?????

what effect does it have on a engine like the IS300??????

will it effect the lifespand of the car

and do supercharger kick in at a certain RPM or is it constant????

and one last thing.... how hard is it to install????

thanks in advance

~_^
 

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supercharger is constant. it doesn't make full boost at lower rpms like turbos do and you definitely lose the boost when you shift(or some of it i mean.) if i remember right it makes the torque curve very flat...maybe i odn't remember right, i don't know. i do know that no matter what, you are shortening engine life, although not as much as you would with a turbo.
 

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there was a topic about this a month ago, do a search for it.

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I rode in a guy's supercharged NSX, and I didn't really like the sound of it, kind of hard on the ears, sounds better without it. But DANG is it fast! S/C gives more top-end rather than low-end power. Supposedly more reliable than turbos, but less power gain.
 

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>> what are the pros and cons of a supercharger?????

More power / more noise, more cost, reduced reliability.

>> what effect does it have on a engine like the IS300??????

Generally superchargers can add port to just about any kind of engine. There is nothing special about the IS300 engine that makes it that different to supercharger.

Well, OK here are some details:

1> Iron block (good for maintaining reliability even with boost)
2> OBD-II engine control. Bad for trying to modify the engine while keeping it emissions legal.
3> Inline-6 - not as good for mounting a supercharger as a v6

>> will it effect the lifespand of the car
Anything that adds power has the potential to reduce the lifespan of various parts.

>> and do supercharger kick in at a certain RPM or is it constant????

Most superchargers are belt driven and make boost right off the line.

Roots type superchargers have very linear boost that makes it feel like a bigger engine.

Centrifugal superchargers tend to make more boost at higher RPMs, and less off the line.

>> and one last thing.... how hard is it to install????

It depends... Not as hard as doing an engine swap, but much harder than mounting a header or an intake tube.


See old topics:
http://www.is300.net/forum_new/Forum1/HTML/003533.html
http://www.is300.net/forum_new/Forum1/HTML/001041.html
http://www.is300.net/forum_new/Forum1/HTML/000640.html
http://www.is300.net/forum_new/Forum1/HTML/003957.html
http://www.is300.net/forum_new/Forum2/HTML/000002.html
http://www.is300.net/forum_new/Forum2/HTML/000052.html
http://www.is300.net/forum_new/Forum2/HTML/000068.html
 

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Originally posted by ckolsen:
I rode in a guy's supercharged NSX, and I didn't really like the sound of it, kind of hard on the ears, sounds better without it. But DANG is it fast! S/C gives more top-end rather than low-end power. Supposedly more reliable than turbos, but less power gain.
All SC are different and make different sounds..but they all emit some kind of whine. Some maybe be as irritating as others.


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Originally posted by mrclam:
supercharger is constant. it doesn't make full boost at lower rpms like turbos do and you definitely lose the boost when you shift(or some of it i mean.) if i remember right it makes the torque curve very flat...maybe i odn't remember right, i don't know. i do know that no matter what, you are shortening engine life, although not as much as you would with a turbo.
The boost on a SC is not constant. The only SC I know of that makes boost low and maintains a constant boost across the RPM is the whipple charger. On most SC boost goes up as RPMs go up. They are linear to each other (ie [email protected], [email protected], [email protected])...but it does make boost right off idle.

The RPM at which Turbos make boost is all dependant on size, motor, and tuning. My friends T51r turbo makes full boost at 5k rpm..and another friend with the same car has a smaller turbo that makes it at 4k rpm.
 

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I just finished reading an excellent article on forced induction in the "VW Performance Handbook" by Greg Raven (I know it's a VW book, but informative nonetheless). It gives a breakdown and synopsis of each type of forced induction.

To answer your questions, it all depends on the type of S/C (i.e. roots, centrifugal, Lysholm/Whipple). Each one produces power at different parts of the rev band. Each one produces a different kind of power curve.

Be careful when researching superchargers because not all are created equal and there are great differences in their efficiency.

Given that TRD decided on a roots/Eaton type blower for the Forerunner, Solara, it's likely that this is the type of design they will use. Personally, I hope they use a centrifugal/vortec type design.
 

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BS,

#1 mistake is not adding the fuel. you always want to have too much in my opinion. I would rather replace spark plugs than motors.

Also a SC,turbo, and NOS all work the same way. They rase the compression of the motor.

Just remember a SC take power to make power. ie. you will be slower off the line because the motor is turning more pullies, (two AC)
Just make sure you have the fuel the motor needs.

A turbo is better. They work off exhaust gasses. meaning that a turbo doesent work the hole time. gives you the all the suden blast of power. and no it will not shorten the life of the motor as long as you dont get crazy and try to put 25lbs off boost through it. Just make sure there is the correct amount of fuel.

I have 32K miles on my supra and have been pushing 1.8 bar. of boost.

Go turbo. I will be. Also on a turbo, you can turn it off if you loan the car to some one to drive. When the wife drives the supra its down to .8 bar. = about 250 rwhp when i drive boost controler gets turned up to 1.8 = 400 rwhp. = handing vipers some toyota A$$


Chech with powerhouseracing.com they were talking about a turbo system for the IS300 at one point. All the do is SUPRA and Lexus work. talk to Jarrett
 

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>> BS,
BS to you too


>> #1 mistake is not adding the fuel. you always want to have too much in my opinion.

You want to have "just right" amount of fuel. If your system isn't able to deliver the exactly right amount (due to imprecise ECU or mechanical metering), then *yes* giving too much fuel is less likely to damage your engine.

>> Also a SC,turbo, and NOS all work the same way. They rase (SIC) the compression of the motor.

NOS Nitrous Oxide Systems do not raise the compression ratio of the motor. They just add an oxidizer that makes the fuel burn with more potency.

>> Just remember a SC take power to make power. ie. you will be slower off the line because the motor is turning more pullies,

Yes, your engine has to make "extra" power to be driving the S/C, but with a "roots type" S/C you are (almost certainly) making more rear-wheel horsepower off the line than you would be without the supercharger.

My supercharged MR2 is "way quicker" off the line than the normally aspirated versions.

My old Rx7 (when it had a big turbo) was slow off the line until you hit 4K RPMs then the turbo would take over and it would blast off.

>> A turbo is better.

This is very debatable.

I would agree that a turbo is better for very high altitude use (like in an airplane), but otherwise I tend to prefer Superchargers.

>> a turbo doesent work the hole (SIC) time.
A turbo is being blasted by exhaust gasses anytime the engine is running. Depending on sizing it may not "spool up" enough to make enough boost to overcome the exhaust restriction it is putting on the car. Some turbo cars feel slow off the line because the turbo plumbing has added a flow restriction on the intake/exhaust until such time as the boost (more than) makes up for those flow restrictions.

There are supercharger installations that use a magnetic clutch on the S/C pulley so that an ECU can engage/disengage the S/C whenever it thinks it is needed (like only when at full throttle or when climbing hills)

>> I have 32K miles on my supra and have been pushing 1.8 bar. of boost.

I have 130K miles on my Supercharged MR2
(well, I only run .9bar but it is still fun)

>> Go turbo.
Go Supercharger...

>> Also on a turbo, you can turn it off if you loan the car to some one to drive.

Turn it off?! You mean adjust the wastegate for less boost, right? It is still "on", just less max boost...

============================================

Supercharger vs Turbo is one of those debates that will never end.

They both provide forced induction and more power, so take your pick!
 

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Discussion Starter #11
hmmmm if you were to have a TRD supercharger in the IS 300 , does putting in a intake system benefit the engine?????

thanks

p.s the reason i'm asking about a supercharge is because i have a friend with a 5-speed accord,2.2 sohc vtec... 50 shot nos, a chip that redline at 10rpm , and all the other basic things.... and his head is getting bigger and bigger by the minute .. saying he is THE ****...... get what i mean
 

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A supercharger will almost certainly come with a new intake system as part of the package.

Since the S/C will blow (boost) the air through, the design of the intake system is less important, and may work better with something other than an intake designed for a normally aspirated engine.

So - no - you probably would NOT want to buy some sort of intake kit if you plan to buy a supercharger kit.

Since your friend's Accord is front wheel drive, I would predict that a modded IS300 (with a decent supercharger install) could outrun it since the Accord will start to run into traction problems once you get some serious mods going.
 

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Well said Teg. You forgot to mention that the turbo system increases the engine bay temperature dramaticaly even when is well insulated. . The supercharger however does not suffer of such predicament.
Originally posted by TEG:
>> BS,
BS to you too


>> #1 mistake is not adding the fuel. you always want to have too much in my opinion.

You want to have "just right" amount of fuel. If your system isn't able to deliver the exactly right amount (due to imprecise ECU or mechanical metering), then *yes* giving too much fuel is less likely to damage your engine.

>> Also a SC,turbo, and NOS all work the same way. They rase (SIC) the compression of the motor.

NOS Nitrous Oxide Systems do not raise the compression ratio of the motor. They just add an oxidizer that makes the fuel burn with more potency.

>> Just remember a SC take power to make power. ie. you will be slower off the line because the motor is turning more pullies,

Yes, your engine has to make "extra" power to be driving the S/C, but with a "roots type" S/C you are (almost certainly) making more rear-wheel horsepower off the line than you would be without the supercharger.

My supercharged MR2 is "way quicker" off the line than the normally aspirated versions.

My old Rx7 (when it had a big turbo) was slow off the line until you hit 4K RPMs then the turbo would take over and it would blast off.

>> A turbo is better.

This is very debatable.

I would agree that a turbo is better for very high altitude use (like in an airplane), but otherwise I tend to prefer Superchargers.

>> a turbo doesent work the hole (SIC) time.
A turbo is being blasted by exhaust gasses anytime the engine is running. Depending on sizing it may not "spool up" enough to make enough boost to overcome the exhaust restriction it is putting on the car. Some turbo cars feel slow off the line because the turbo plumbing has added a flow restriction on the intake/exhaust until such time as the boost (more than) makes up for those flow restrictions.

There are supercharger installations that use a magnetic clutch on the S/C pulley so that an ECU can engage/disengage the S/C whenever it thinks it is needed (like only when at full throttle or when climbing hills)

>> I have 32K miles on my supra and have been pushing 1.8 bar. of boost.

I have 130K miles on my Supercharged MR2
(well, I only run .9bar but it is still fun)

>> Go turbo.
Go Supercharger...

>> Also on a turbo, you can turn it off if you loan the car to some one to drive.

Turn it off?! You mean adjust the wastegate for less boost, right? It is still "on", just less max boost...

============================================

Supercharger vs Turbo is one of those debates that will never end.

They both provide forced induction and more power, so take your pick!
 

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From what I know about superchargers:

A roots type supercharger pretty much will give you instant max boost as soon as you crack the throttle and in general are better for low - mid rpm applications. A centrifugal type has a more gradual increase in boost as RPM's increase and generally I think you can run more rpms.

From what I know about turbos, max boost is not instant, but I think you can acheive max boost very quickly depending on the system and restrictions you have.

JJ
Waiting for 2002 Manual...

Originally posted by brokenhearted:
i don't know much about supercharger

what are the pros and cons of a supercharger?????

what effect does it have on a engine like the IS300??????

will it effect the lifespand of the car

and do supercharger kick in at a certain RPM or is it constant????

and one last thing.... how hard is it to install????

thanks in advance

~_^

 

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TEG: the air that we breathe is approximately 5 parts nitrogen to one part oxygen
nitrous for automobiles is approximately 3 parts nitrogen to one part oxygen
there are more parts of air to a specific volume area, when compared to breathable air. that is where the extra power comes from, more oxygen molecules per measured area = more power, same with other forms of forced induction.

i don't know if that is what you meant by: "They just add an oxidizer that makes the fuel burn with more potency."
but i don't think that is a good way of phrasing it.


KERR- all properly tuned supra turbos make atleast 285 rwhp, stock, so i don't see how you are making only 250rwhp @ 11 or 12 psi.

you also aren't making 1.8 bar, or 26.5 psi, with the stock turbos.

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NOx is reactive, while N2 is not, so I'm not sure what you mean. I thought it has to do with compression ratios rather than chemical composition?

Originally posted by IS300GTE:
TEG: the air that we breathe is approximately 5 parts nitrogen to one part oxygen
nitrous for automobiles is approximately 3 parts nitrogen to one part oxygen
there are more parts of air to a specific volume area, when compared to breathable air. that is where the extra power comes from, more oxygen molecules per measured area = more power, same with other forms of forced induction.

i don't know if that is what you meant by: "They just add an oxidizer that makes the fuel burn with more potency."
but i don't think that is a good way of phrasing it.


KERR- all properly tuned supra turbos make atleast 285 rwhp, stock, so i don't see how you are making only 250rwhp @ 11 or 12 psi.

you also aren't making 1.8 bar, or 26.5 psi, with the stock turbos.
 

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The turbo will be more efficient partly because it is not limited by the drag caused by the engine via the supercharger pulley and belt. In an S/C the boost is largely limited via pulley size. Again, a certain amount of efficiency will be lost to friction and drag as a result of the belt.

I agree that turbocharging is more efficient since it is not "dragged" down by any engine drag from belts or pulleys, but additional factors come into play. There is increased "plumbing" when dealing with turbos and their respective aparatuses (i.e. waste gates, blow-off valves, intercollers. In addition, the turbo and associated housing(s) itself needs care to prevent damage from heat.

IMO the "mechanical" nature of a supercharger seems to be an easier and simpler concept of forced induction and one that I prefer. However, if your performance desires tend towards efficiency and increased complexity of turbocharging, then that is the route for you.
 

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Nitrous Oxide (N2O) and Nitrogen (N2) are different things...

I got this from a FAQ on N2O in general off the net: "In racing, nitrous is injected into the air intake to increase power. It does this in two ways. First, there is 1 oxygen atom per molecule of gas (compared to 0.4 for regular air). Second, when the liquid in the tank vaporizes, it comes out very cold. The effect of both of these is that you can cram a lot more oxygen into your cylinders. Since fuel (gasoline, at least) takes up far less space, you can easily increase the amount. Having increased the quantities of both fuel and air, you have increased the pressure on the power stroke.

O2 gas would theoretically be better, but you need a much thicker (heavier) tank to get it to liquefy, and it is much more of a hazard if something goes wrong."

And also: "Although nitrous oxide is quite unreactive at room temperature, when heated, an EXOTHERMIC RXN occurs!

2N2O (g) --> 2N2 (g) + O2 (g)

So how is this beneficial? We can see that 2 moles of gas results in 3 moles of gas... Here is some chemistry: if the volume stays the same but the moles of gas increases in the system, what happens? THAT'S RIGHT! This increases the pressure of the gas tank! When this occurs in the combustion chamber, it provides extra boost to the piston and liberates more heat. With this increase in O2, cars can combust fuel much more efficiently. Also, the nitrogen buffers the combustion pressure and the heat of the N2O vaporization reduces the intake temperature for the cars. Thus providing a cooling system!"

And: "Nitrous oxide is made up of 2 parts nitrogen and one part oxygen (36% oxygen by weight). During the combustion process in an engine, at about 572 degrees F., nitrous breaks down and releases oxygen. This extra oxygen creates additional power by allowing more fuel to be burned. Nitrogen acts to buffer, or dampen the increased cylinder pressures helping to control the combustion process. Nitrous also has a tremendous "intercooling" effect by reducing intake charge temperatures by 60 to 75 degrees F."

Note: edited my 0s to Os.



[This message has been edited by HIBBoyScott (edited December 19, 2000).]
 

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instead of retyping it all, i will just copy what HIBBOYSCOTT brought to the discussion:

"And: "Nitrous oxide is made up of 2 parts nitrogen and one part oxygen (36%
oxygen by weight). During the combustion process in an engine, at about 572
degrees F., nitrous breaks down and releases oxygen. This extra oxygen creates
additional power by allowing more fuel to be burned. Nitrogen acts to buffer, or
dampen the increased cylinder pressures helping to control the combustion
process. Nitrous also has a tremendous "intercooling" effect by reducing intake
charge temperatures by 60 to 75 degrees F."


-thanks scott!


Originally posted by ckolsen:
NOx is reactive, while N2 is not, so I'm not sure what you mean. I thought it has to do with compression ratios rather than chemical composition?



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BTW

Q: Does N2O raise cylinder pressures and temps?

A: Yes. Due to the ability to burn more fuel, this is exactly why nitrous makes so much power
 
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