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[neilio]

rnicklaus wrote on Sat, 15 November 2008 12:35

I heard someone say on Real Time last night that the oil companies should bail out GM and Ford.

i couldnt agree more on that by the way, or at least they should buy them....they are as symbiotic as gets already...would be like marrying the mistress, when the wife is already gone...

they really should do this.

not cause i want to see big oil succeed any more neccessarily, but because they have fostered much of detroits faulty towers,er ways...

[ssltech]

neilio wrote

question, and i know a little about engines,as ive been a car fan all my life, isnt a supercharger actually better for everyday day driving for effiency, as the power band is available thorughout all rpm range? and as well no trouble with detonation, intercoolers, wastegates etc?

Well... Define 'Better'.

As for 'no trouble with wastegates, detonation, intercoolers etc', MOST superchargers are low-boost affairs, and they avoid intercoolers because they don't heat up the air very much, because they don't SQUASH it very much... likewise, they don't increase the tendency to detonate very much if they don't squash the air very much... so it sounds very much as though you're really only talking about LOW pressure superchargers.

Wastegates are a way of managing excess pressure, and are the bain of upstream-metered-air systems, where DIVERTER VALVES are often used in their place. I think every supercharger system that I've seen recently has some kind of diverter valve, otherwise they'd be boosting at idle... and fuel economy would be utterly destroyed.

My supercharged VW has a diverter valve on it (although it differs in that it's there exclusively to manage boost under LOW throttle-demand conditions), and neither of my Turbocharged cars has a wastegate or 'blowoff' valve: both are upstream-metered systems, so both use 'recycling' divert-valve technology, to keep the Mass airflow representative of the engine's air intake, and hence the amount of FUEL that it requires for a stoichiometrically-correct mixture.

..Certainly, it's inaccurate to say that a supercharger doesn't need an intercooler any more than a turbo does... the more you boost, the more you heat the charge by compression, the more you need an intercooler.

Also, there's more than one type of supercharger: the one most people think of is the Eaton/Rootes/Whipple blower, which is a POSITIVE DISPLACEMENT type: these DO produce boost at low revs -even at idle- and again I suspect that's what you are thinking of... the other type is the centrifugal supercharger, which produces rising boost with engine revs... Pros and cons for both of them I'm afraid: The positive displacement ones make boost as soon as you crack the throttle open, whereas the centrifugal ones don't. -This I suspect is what you're talking about with "range" of revs. -However, they DON'T tell you that at high revs this type runs out of puff in comparison to the centrifugal supercharger, which should probably out-blow a PD blower above 4,000 engine revs.

Two of my friends have identical C5 Vettes, both are supercharged, one with a PD blower from Magnusson, the other with a centrifugal blower. -Same engine, but the two Forced-induction systems make their characteristics QUITE different. One leaps off the line like a scalded cat, but runs out of puff at the top end, whereas the other is slightly more gentle (not that a 'Vette should ever be lacking in torque!) off the line, but explodes as the revs build...

-Which is "better"? -I'm damned if I can tell you, but they're BOTH an absolute blast to drive!

neilio wrote

i used to have an acura integra, and now the missus has a mazda 5 thingie(which we totally dig), both those cars could use a little more juice, and people always say well, you could turbocharge them, but id rather go supercharging as in everyday driving they are "better"(ambigious term , i know)...what say audio guy, particularily keith on this subject...why not supercharge instead?

When you say 'Mazda 5' do you mean the MX-5 Miata? -The Miata is a handling blast, and TONS of fun at Auto-Cross weeekends. -They make a "bolt-on" supercharger kit for at least the series one... -If you mean the SUV thingie, then I probably wouldn't juice the motor much, and even then not without first significantly upgrading the brakes and tyres... and probably equally significantly increasing the rear anti-sway rating... "More power" needs more control and the Mazda SUVs tend to have a reassuring sense of grip, although it disappears at the limit in a rather sudden fashion, instead of alerting you... -and that's a dangerous amount of mass high off the ground to take risks with...

The 'Teg might be a better candidate, but both are fairly high compression motors, so you probably coludn't go at ALL above 6PSI peak boost on 93 octane fuel. -That means that through most of the range you'd get 2-3 PSI, although that's a poorly-educated guess on my part, because the Integra is cammed to breathe and rev quite freely compared to say a VW motor.

Superchargers are a LOT less scary to fit aftermarket than turbos though... Turbos require oil for cooling, and some also ALSO need engine coolant to be pumped through a jacket around the lubrication path... along with some means of monitoring the temperature after shut-off, and an electric pump to FORCE the coolant through the jacket to prevent the bearings from caking up (these are commonly known as "wet" turbos).

Turbos are indeed more convoluted, but they do produce superior on-paper peak specs, and in hard performance terms are probably more 'capable'. PD superchargers are simpler to retrofit, but the gains are modest, and boost -no matter WHICH method you use to generate it- has to be LIMITED by fuel detonation characteristics and piston sweep/head volume compression ratio.

I've played with both and I've had lots of fun with both. If I ever convert another engine to forced-induction, it'll probably be an air-cooled Porsche with a dry-sump system... Just because I want to do it SO-OOO much!  

Keith

[YZ]

Well,

All other discussion aside, one cannot dismiss the fact that a variable tax on gasoline designed to stabilize its long-term price and taxing large-engined cars more than small-engined ones has been already implemented with success in other countries and achieved the desired results, so it is somewhat of a moot point.

And the USA had already tried to give incentives to their auto industry in the past for several purposes (greener cars, less consumption et al) but the only time it really worked was when credit was given to the end-buyer; nearly all other times when tax money was given to the auto makers for a specific purpose, it was misspent and did not fulfill its intention.

When did the US Government had success with the auto industry? when it _mandated_ emissions control and when it established fuel consumption goals that if not met would result in fines.

So what to do now that the 'big 3' are short for cash due to not having products that captivate the buyers, a situation that if not resolved may lead to a worsening economic scenario for everybody?

Intervention. In the ample sense of the word. The Government steps in, puts new people in charge of product development, puts controllers in the finance areas, negotiates temporary changes in worker's benefits, cuts executive salaries, eliminates bonuses and perks, re-evaluates the current product lineup  eliminating low-selling models, puts efficiency experts to boost productivity and so forth.

Some people will lose their jobs.

No free lunch.

[bblackwood]

The big three are hurting because they suffer from the same issue many Americans do - an almost immoral refusal to be conservative with their resources.

Conservatism - not republicanism, but true conservatism - has been dying in the US for decades and we're just beginning to reap what we've sown for so long. Until/unless we solve this problem at its core, we're just applying band-aids to massive wounds...

[T. Mueller]

I wrote Brad Blackwood in for President.

[YZ]

bblackwood wrote on Mon, 17 November 2008 14:23

The big three are hurting because they suffer from the same issue many Americans do - an almost immoral refusal to be conservative with their resources. Conservatism - not republicanism, but true conservatism - has been dying in the US for decades and we're just beginning to reap what we've sown for so long. Until/unless we solve this problem at its core, we're just applying band-aids to massive wounds...

Ok.  can't disagree much with the first part.

But sometimes you've got to act in urgency and apply a band-aid-like interim solution, just like in a massive wound you first try to stop the hemorrhage to then treat it properly.

_IF_ it is true that the automaker problems if untreated will cause a domino effect, then the measures I suggested above make sense.

But you don't change a whole society's attitude in a couple of days, and if GM et al are just a symptom (a major one) it has to be treated first while slower-acting medicine is applied to make the greater evil recede.

[neilio]

ssltech wrote on Sun, 16 November 2008 17:57

neilio wrote question, and i know a little about engines,as ive been a car fan all my life, isnt a supercharger actually better for everyday day driving for effiency, as the power band is available thorughout all rpm range? and as well no trouble with detonation, intercoolers, wastegates etc? Well... Define 'Better'. As for 'no trouble with wastegates, detonation, intercoolers etc', MOST superchargers are low-boost affairs, and they avoid intercoolers because they don't heat up the air very much, because they don't SQUASH it very much... likewise, they don't increase the tendency to detonate very much if they don't squash the air very much... so it sounds very much as though you're really only talking about LOW pressure superchargers. Wastegates are a way of managing excess pressure, and are the bain of upstream-metered-air systems, where DIVERTER VALVES are often used in their place. I think every supercharger system that I've seen recently has some kind of diverter valve, otherwise they'd be boosting at idle... and fuel economy would be utterly destroyed. My supercharged VW has a diverter valve on it (although it differs in that it's there exclusively to manage boost under LOW throttle-demand conditions), and neither of my Turbocharged cars has a wastegate or 'blowoff' valve: both are upstream-metered systems, so both use 'recycling' divert-valve technology, to keep the Mass airflow representative of the engine's air intake, and hence the amount of FUEL that it requires for a stoichiometrically-correct mixture. ..Certainly, it's inaccurate to say that a supercharger doesn't need an intercooler any more than a turbo does... the more you boost, the more you heat the charge by compression, the more you need an intercooler. Also, there's more than one type of supercharger: the one most people think of is the Eaton/Rootes/Whipple blower, which is a POSITIVE DISPLACEMENT type: these DO produce boost at low revs -even at idle- and again I suspect that's what you are thinking of... the other type is the centrifugal supercharger, which produces rising boost with engine revs... Pros and cons for both of them I'm afraid: The positive displacement ones make boost as soon as you crack the throttle open, whereas the centrifugal ones don't. -This I suspect is what you're talking about with "range" of revs. -However, they DON'T tell you that at high revs this type runs out of puff in comparison to the centrifugal supercharger, which should probably out-blow a PD blower above 4,000 engine revs. Two of my friends have identical C5 Vettes, both are supercharged, one with a PD blower from Magnusson, the other with a centrifugal blower. -Same engine, but the two Forced-induction systems make their characteristics QUITE different. One leaps off the line like a scalded cat, but runs out of puff at the top end, whereas the other is slightly more gentle (not that a 'Vette should ever be lacking in torque!) off the line, but explodes as the revs build... -Which is "better"? -I'm damned if I can tell you, but they're BOTH an absolute blast to drive! neilio wrote i used to have an acura integra, and now the missus has a mazda 5 thingie(which we totally dig), both those cars could use a little more juice, and people always say well, you could turbocharge them, but id rather go supercharging as in everyday driving they are "better"(ambigious term , i know)...what say audio guy, particularily keith on this subject...why not supercharge instead? When you say 'Mazda 5' do you mean the MX-5 Miata? -The Miata is a handling blast, and TONS of fun at Auto-Cross weeekends. -They make a "bolt-on" supercharger kit for at least the series one... -If you mean the SUV thingie, then I probably wouldn't juice the motor much, and even then not without first significantly upgrading the brakes and tyres... and probably equally significantly increasing the rear anti-sway rating... "More power" needs more control and the Mazda SUVs tend to have a reassuring sense of grip, although it disappears at the limit in a rather sudden fashion, instead of alerting you... -and that's a dangerous amount of mass high off the ground to take risks with... The 'Teg might be a better candidate, but both are fairly high compression motors, so you probably coludn't go at ALL above 6PSI peak boost on 93 octane fuel. -That means that through most of the range you'd get 2-3 PSI, although that's a poorly-educated guess on my part, because the Integra is cammed to breathe and rev quite freely compared to say a VW motor. Superchargers are a LOT less scary to fit aftermarket than turbos though... Turbos require oil for cooling, and some also ALSO need engine coolant to be pumped through a jacket around the lubrication path... along with some means of monitoring the temperature after shut-off, and an electric pump to FORCE the coolant through the jacket to prevent the bearings from caking up (these are commonly known as "wet" turbos). Turbos are indeed more convoluted, but they do produce superior on-paper peak specs, and in hard performance terms are probably more 'capable'. PD superchargers are simpler to retrofit, but the gains are modest, and boost -no matter WHICH method you use to generate it- has to be LIMITED by fuel detonation characteristics and piston sweep/head volume compression ratio. I've played with both and I've had lots of fun with both. If I ever convert another engine to forced-induction, it'll probably be an air-cooled Porsche with a dry-sump system... Just because I want to do it SO-OOO much!   Keith

well as to the mazda, yes the suv thingie, and no i would never add a supercharger without stiffening and seriously upgradeing the braking...as far as tires go, its has 18's, and 45 series tyres(with a y, for you ) stock... and it produces 155 bhp stock, if it had 180, or 190, it could be perfect...which is why id go with supercharging, and i do mean the eaton/roots type screw...as it would be midrange, off the line, merging on freeway type of power required...

thanks for the reply...very good stuff.

[RSettee]

bblackwood wrote on Mon, 17 November 2008 10:23

The big three are hurting because they suffer from the same issue many Americans do - an almost immoral refusal to be conservative with their resources. Conservatism - not republicanism, but true conservatism - has been dying in the US for decades and we're just beginning to reap what we've sown for so long. Until/unless we solve this problem at its core, we're just applying band-aids to massive wounds...

Agreed on all fronts. It's a shame that the Neocons are masquerading as conservatives, because I think that conservatism can definetely have some merit. Right now, though, I think that Liberal works so well, because you need to spend money to make money. My fears about conservatives (or at least the Neocon type) is that they're conservative about bettering the economy and the lives of most of the working class, but liberal towards big corporate spending and whatever particular groups, policies or agendas that they believe in and favor.

[rnicklaus]

It did not go over too well today that the "Big 3" CEOs showed up in Washington via 3 separate private jets.

There's some forward thinking while asking for a bailout.

[Nick Sevilla]

Hank Alrich wrote on Mon, 10 November 2008 19:56

Why are Toyota and Honda able to profitably manufacture relatively reliable and efficient vehicles in the United States if the problems are all about the cost of labor? US industry in general seems always happy to blame labor for problems, while the brass continue to rake in unconscionable amounts in salaries and bonuses.

The "Brass" is also part of Labor costs.

The Labor Unions still refuse to re-negotiate anything. This will put these automakers under.

You cannot compete with foreign automakers when they pay less for labor, and less for parts as well. It simply is not done.

How we did it here for the last 30 years? IMPORT TARIFFS and IMPORT TAXES.

Now that the Japanese automakers have factories in the USA, Canada, and Mexico, these tariffs and taxes can no longer be placed on them, because they are no longer foreign cars.

This is a fine mess, no doubt, I hope that our Congress can force these three car makers to restructure, and survive, rather than dole out money, and fail anyways.