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Discussion Starter #1
Wolf in sheeps clothing???

Doug, EAT YOUR HEART OUT


The Lingenfelter Twin Turbo C5 Corvette is AWESOME
Go over to our site and see High Res Video Footage of this meek, stock looking 650hp BEAST . Listen to the beautiful sound of the Turbo as this vette passes by at 225mph!!!!
The Car & Driver Top Ten footage is also Up now.Here's the link to Our IS300 WebSite Justin’s IS300 Page Also Other Fun & Informative Stuff.

High Res Video Of Our IS300 traveling down the highway...

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JUSTIN & DENISE C. OWNERS OF THE ONE-OF-A-KIND IS300

[This message has been edited by smra (edited December 22, 2000).]
 

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smra i got a question for you. do you know how long a turbo'd car can travel at top speed before it goes kaboom?

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Solar Yellow/Black IS300
 

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Discussion Starter #3
Originally posted by Lexus_IS300:
smra i got a question for you. do you know how long a turbo'd car can travel at top speed before it goes kaboom?

NO.....
 

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Originally posted by Lexus_IS300:
smra i got a question for you. do you know how long a turbo'd car can travel at top speed before it goes kaboom?
Turbo cars are only under boost during acceleration. If you're maintaining a constant speed, you're not accelerating and you won't be under boost. So you can drive at top speed just as long as anyone else...


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Tony
'01 Spectra Blue
'94 Turbo Miata
 

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Tony, I don't think that is necessary true. When you are full throttle and at max RPM, you are using getting some turbo boost, if not all. The reason is that your exhaust is going at its absolute max speed and therefore you are spinning the turbine toward at the highest rpm and therefore generate boost.
However, you are right about no boost under regular freeway cruising because you are barely on the throttle and the exhaust gas going through the turbine housing is minimal and slow.
 

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Originally posted by Daniel:
Tony, I don't think that is necessary true. When you are full throttle and at max RPM, you are using getting some turbo boost, if not all. The reason is that your exhaust is going at its absolute max speed and therefore you are spinning the turbine toward at the highest rpm and therefore generate boost.
A turbo spins not by exhaust gas velocity, but by exhaust gas heat energy. The engine must be under load to generate heat. If you keep the car in neutral you can run it up to redline all day long and you will get 0 boost. You have to put load on the engine for the turbo to spin.

However, you are right about no boost under regular freeway cruising because you are barely on the throttle and the exhaust gas going through the turbine housing is minimal and slow.
If I'm cruising at 100 mph in my turbo miata, I am not "barely on the throttle". Nevertheless, my car is in a 0 boost condition...When I accelerate to pass, however, boost rises very quickly.


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Tony
'01 Spectra Blue
'94 Turbo Miata

[This message has been edited by webmaster (edited December 23, 2000).]
 

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So Tony, if this car is at WOT say 6500 rpm's at terminal velocity, you think the turbo is providing "0" boost?" Thats funny!
Why should I eat my heart out? I actually have one..
 

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Discussion Starter #8
Yea right....

Sure you have a Twin Turbo Lingenfelter C5...

Pull my other leg while you're at it.
 

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Originally posted by Doug:
So Tony, if this car is at WOT say 6500 rpm's at terminal velocity, you think the turbo is providing "0" boost?" Thats funny!
If you're maintaining a constant speed, thus not accelerating, then yes, 0 boost.




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Tony
'01 Spectra Blue
'94 Turbo Miata
 

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The funny thing about you guys is that you think that you know something. Just because you're broke doesn't mean I wont step up to some engine mods. But first things first, you need a fifty thousand dollar car to start with, then, and I know this may intimidate you, but the packages START at $10,000, LMAO. My guess is that you had never heard of LPE prior to the Motortrend segment. HEHE
 

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Originally posted by Doug:
No offense Tony, but you are wrong
http://www.xmission.com/~dempsey/shelby/turbo101.htm

Doug, please show me where I'm wrong. That article talks in some very broad generalities and does not address our discussion regarding the production of boost under load. If you need some better sources, I can give you Corky Bell's phone number.


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Tony
'01 Spectra Blue
'94 Turbo Miata
 

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You've got to be kidding me, the exhaust gases, which propel the turbo (not heat) are generated by combustion, regardless of whether the car is acclerating, if the engine is turning say 3000 rpm's that will generate a certain level of boost regardless of whether the car is acclerating or at a constant speed. If the car is at WOT and at a terminal speed the turbo will be at its' maximum boost level even if the car is actually slowing down do to drag. Your heat theory would suggest that a car that runs hot would generate more boost across the board, ie sitting in traffic and your headers start heating up and the boost gauge starts registering boost?????? I don't think so.
 

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Discussion Starter #14
Originally posted by Doug:
The funny thing about you guys is that you think that you know something.

We Do Know Something Dougie !

Just because you're broke doesn't mean I wont step up to some engine mods.

Sorry, but We're Far from Broke Dougie


My guess is that you had never heard of LPE prior to the Motortrend segment. HEHE

Finally right about something, No I have never heard of Lingenfelter before the
CAR & DRIVER Segment, not MOTOR TREND Dougie

So again I say EAT YOUR POOR HEART OUT!!

And Merry Christmas to You too Dougie.



[This message has been edited by smra (edited December 24, 2000).]
 

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Originally posted by Doug:
You've got to be kidding me, the exhaust gases, which propel the turbo (not heat) are generated by combustion, regardless of whether the car is acclerating, if the engine is turning say 3000 rpm's that will generate a certain level of boost regardless of whether the car is acclerating or at a constant speed.
Wrong. The engine must be under load. Do you have a car with a turbo? Go outside right now and start it up and sit it in. Idling? Is there boost? No. Rev up to 3000 rpm in neutral, boost? No. Rev to redline, boost? No.

If the car is at WOT and at a terminal speed the turbo will be at its' maximum boost level even if the car is actually slowing down do to drag. Your heat theory would suggest that a car that runs hot would generate more boost across the board, ie sitting in traffic and your headers start heating up and the boost gauge starts registering boost?????? I don't think so.
That's not what I'm saying. There is considerably more heat energy when the engine is under load than when it's not. Sitting in traffic is idling.

If you were right Doug, turbos wouldn't have any lag of any kind at all. They'd make boost the instant you turned the engine on.


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Tony
'01 Spectra Blue
'94 Turbo Miata

[This message has been edited by webmaster (edited December 24, 2000).]
 

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>> Tony wrote,
>> Turbo cars are only under boost during acceleration. If you're maintaining a constant speed, you're not accelerating and you won't be under boost.


Urgh.

Tony - as much as I hate to disagree with you here, many turbo cars will be under alot of boost at top speed.

Maybe if it has a really low (artificial) top speed governor (electronic or gearing) you might find you could cruise at top speed without boost, but for most turbo cars that is simply not the case.

Let me try to explain it in a way I hope you can understand:

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A car without an artificial rev limiter is primarily limited in top speed by wind resistance (drag). You have to make real horspower to overcome that drag. You make more power with turbo boost so you need that boost to maintain top speed.
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Now here are some situations where a car could have a top speed without needing boost:

If the top speed is determined not by wind resistance, but rather by having the engine stop at the rev limiter (redline) or at a fixed speed (due to electronic controls) it is _possible_ that you could make enough power (depending on the engine) to maintain top speed even without needing any turbo boost.

Lets pretend for instance that your car came with only one gear and that gear was like first gear in a typical car. If you rev to redline (say 30mph at 5500rpms for example) and then just cruise along that would be your top speed (30mph) due to the gearing. If you had an 8liter v8 with a turbo you could expect to be able to maintain 30mph without the need for any registered boost.

Now keep in mind that the turbo is spinning, and it is pushing air through the intake, it is just that the engine is breathing more than the turbo is blowing so you still get a vacuum showing on your boost gauge.

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For many cars, top speed is achieved with full throttle in the top gear. The car is "under load" due to wind resistance. This engine is making similar HP to what you would be doing while accelerating (in a low gear/lower speed) with full throttle. Either case a turbo should be making boost (full throttle under load).

Now if we really want to get into more detail we would need to know things about the altitude, head/tailwinds, and inclination of the road to determine just how much boost you are going to need/get at a given speed and throttle position.

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Now back to Lexus_IS300s original comment:

>> do you know how long a turbo'd car can travel at top speed before it goes kaboom?

In a general case, most turbo cars are engineered to be able to cruise at top speed (even with max boost and max hp) for a _LONG_ time before anything fails.

Low production, high HP (I think that Lingenfelter qualifies) machines are typically less reliabile than conservatively engineered "factory stock" cars, but there is no way to tell (short of actually testing one) how long it could run at top speed before something failed. If they did everything right it still might be able to get to 100,000K miles even running at top speed (although I would expect something more like 5-10K miles if that).

Now I would bet that there are alot of German Porsche 911 Turbos that have run "flat out" on the Autobahn for many thousands of Kms without any problems. The turbo Porsches are designed for that kind of use.

When car magazines do "top speed shootout" tests against various cars, the aftermarket tuner cars tend to outdo the factory cars (trap speed wise), but they also tend to have a high failure ratio when testing aftermarket turbo cars at top speed.

So - Lexus_IS300 - I could see why you would wonder about turbo cars going "kaboom" at top speed - it is because alot of tuners find it easy to "crank up the boost" to get outrageous HP even though the base engine isn't designed to han
 

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This isn't going anywhere, yes I have had turbocharged cars. Your argument does not make sense to me. The turbo is turned by exhaust gases turning an impeller that is on the same shaft as the compressor blade which in turn compresses the intake air. Heat is actually a negative component of turbochargers as they get very hot and consequently heat the charge air, one reason you frequently see intercoolers used in conjunction with Turbochargers. I don't have a Phd in this area but it seems we are disagreeing on the fundamental operation of how the turbocharger benefits the motor.

SMRA you are a wannabe....... so when I get a Turbo Porsche or a Modena, do I still eat my heart out? I'm not poor enough to after other peoples material possesions (literally or emotionally),so excuse me if I can't relate, if I want one I just work hard and go buy one. Who the hell do you think is responsible for buying this kind of stuff anyway, we sure as hell know its not you LMAO!

[This message has been edited by Doug (edited December 24, 2000).]
 

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Originally posted by Doug:
This isn't going anywhere, yes I have had turbocharged cars. Your argument does not make sense to me. The turbo is turned by exhaust gases turning an impeller that is on the same shaft as the compressor blade which in turn compresses the intake air. Heat is actually a negative component of turbochargers as they get very hot and consequently heat the charge air, one reason you frequently see intercoolers used in conjunction with Turbochargers.
Turbo's are turned by expanding hot exhaust gases. They got hot because they spin extremely fast. That is not why intercoolers are used. They do not cool the turbo, nor does the hot turbo heat the intake air. Intercoolers cool the compressed intake charge which is heated due to being compressed.

TEG, I always said cruising and thus not accelerating. Maintaining top speed against drag is certainly load and would push the car into boost, agreed. But the instant you're not accelerating (or trying to), there will not be any boost.


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Tony
'01 Spectra Blue
'94 Turbo Miata

[This message has been edited by webmaster (edited December 24, 2000).]
 

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Discussion Starter #20
Originally posted by Doug:

SMRA you are a wannabe.......

Wannabe what Doug? Im where I WANNABE in life. Why are you so ANGRY ALL THE TIME?


so when I get a Turbo Porsche or a Modena, do I still eat my heart out?

Don't know... Do You? I don't care what you drive man....


I want one I just work hard and go buy one.

Good for you....I think thats how it works with most people man...

Who the hell do you think is responsible for buying this kind of stuff anyway

Buying what stuff Doug?? Performance Parts?? You should already know, but I'll tell you again. Im not into modifying cars.
And just like you I can buy whatever I want too. But Im a Practical Man.....
But I love High Performance Imports and the New Corvettes...C5....Z06.... but they aern't very practical for a Family Man like me.
 
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