andrew3616

What is it exactly? I was reading that the skyline has a twin turbo. How much better is the skyline engine than ours?

Maxman2000

iTrader: (5)

Alot better, it's a in-line 6 and in-line engine have more power than V's

lyonsd

Not neccessarily.

maxGTRvq35de

twin turbo means boost. the internals are good in a skyline for some where up to 600hp that is pretty much all stock. with just turning up the boost and fuel. skyline engine are much stronger than our engines. im not sure what the 3.0 and 3.5 internals hp rating is on out cars but i dont think it is 600hp. our cars are great but skyline are the best car ever make .

Maxman2000

iTrader: (5)

I'm a little today. I hope I get to own a skyline someday in my life. Even for just one day.

Maxman2000

iTrader: (5)

A whole lot of boost . Like opening up a can of whoop azz!!

andrew3616

well isnt there two turbos?

Maxman2000

iTrader: (5)

Foe the max??

andrew3616

in a twin turbo setup there is two turbos right, but only one intake?. Is it just that one turbo does not provide enough boost so they go double?

Maxman2000

iTrader: (5)

I'm sorry but I'm not getting you. Going double? You mean that only one turbo is providing enough power. I'm a little slow this morning.

andrew3616

what i dont understand is how you can have to turbos? Like on the maxima there is only one itake so how could you put two turbos on?

Maxman2000

iTrader: (5)

Well you could customize the exhaust manifold and then relocate the battery to the trunk and then put the turbos where the battery used to be and do some more customizing for the intakes and outputs.

Maxman2000

iTrader: (5)

Or if you got the money, get a skyline engine or a supra 2JZ-GTE TT enine and do a engine swap. You'd have to make the max RWD if you wanted to go that far.

wantasupra3

AWD + 2.6 inline 6 + twin turbos + badass Trans = Maxima Ownage!!!

lyonsd

A turbocharger consists of two parts, connected by a shaft: the turbine and the compressor. Hot exhaust gases spin the turbine, which in turn spins the compressor. The compressor draws in fresh air and compresses (and heats) it into the intake charge. Intercoolers are sometimes used to cool the intake charge. The hotter the intake charge is the more likely it is to detonate in the cylinder, which is not a good thing.

A twin turbo system would consists of two identical turbos. On a "V" engine, each turbo is spooled by each bank of cylinders. If an intercooler is present, both compressors feed air into the intercooler, and then on to the intake manifold. Just as an exhaust system consists of a "Y" pipe to direct two pipes into one, so can this be applied to the intake charge.

Some cars used a dual turbo setup. Two turbos are used, but they are not necessarily identical to one another. Turbos, like many other engine components, operate most effeciently at a certain speed or rpm. So in one of these dual turbo systems, one turbo operates best at low RPM, while the other provides more efficiency at a higher RPM. This is how the Supra works. Each turbo has a "compressor map" which you can read to determine the best application for the turbo.

Generally speaking, an inline engine would be better with a single turbo. And a "V" engine would be better with a twin setup. Although some "V" engines use a single turbo setup. Like the Buick Grand National. The turbo is located at the passenger-side front of the engine. The passenger-side bank of cylinders feeds the exhaust directly into the turbine. The driver-side bank of cylinders feeds into a crossover pipe which merges with the passenger side bank, and then into the turbine.

The reason a twin turbo setup would work better on a "V" is because in a single setup some heat is lost from one bank as it travels through the crossover pipe to the other side and into the turbine. But in an inline engine all the cylinders are feeding straight into the turbine.

ychuw

i want turbo in my max!

jjs

Before I go turbo, I will get a G35 or other rear wheel drive car that can make full use of it.

2k2kev

good description, but you're making it sound like heat is a good thing... it's not (hence the intercooler). Everywhere you said (and heats) you should have also included "that's bad" or "that's undesirable."

[maxi-overdose]

iTrader: (3)

TT means using two smaller turbo to boost your engine in order to reduce turbo lag instead of one large turbo. In the case of Supra, there's a small turbo and a large turbo. The small turbo spools faster and boost the low end. Once it goes to the top end, the larger turbo will kick in. lyonsd has pretty good write-up about this.

or you can have a single large turbo with small shots of N2O to help the low end...several SC people also use this set-up because SC's power comes in at the top end.....aka, boost and juice.

lyonsd

I assumed that was implied.

Maxman2000

iTrader: (5)

You gotta bounce the needle off the red line a couple of time to let the turbo spool up to give you maximum power.

2k2kev

with a question like "does twin turbos mean there are two?" I wouldn't assume anything.

Maxman2000

iTrader: (5)

Also forgot to post that I was watching the show truck and they were talking about superchargers and turbochargers. They recomend superchargers for gasoline engines and turbos for deisels. I didn't really hear why but that's what I heard.

vqman

finally someone gets it right...

I read through 15 posts to get to yours...

yes the 2 turbos are used to reduce "turbo lag" that is common with one BIG turbo.

-vq

jjs

I think that in general, gasoline engines rev at a higher level that diesel counterparts. High revs are good for SC's since they are crank/belt driven. Lower revs but high exhaust help spin a turbo as in from a diesel.

I think....

Maxman2000

iTrader: (5)

I think that's exactly what they said

maximamaybe

I might be wrong, but when I saw a skyline at one of the DNE maxima meets, it had 2 Apexi intakes on it. The Supras only have one, but I think the skylines have 2.

Maximam

LMAO!

bigmaxx

Just wondering. Since the SC gets its power at the top end, has anyone ever added a small turbo to an SC setup to get power at the low end. I've never heard of a car with a supercharger and a turbocharger on the same engine. Does it exist? Is it possible?

jjs

I would imagine, among other things like plumbing, a big problem would be the potential for overboosting the engine. BOTH produce boost during the whole rpm band, just in differing ranges and to differing degrees. Not sure how you determine and control a 'crossover point' which is still safe for the engine but also helps 'wash' the increase of one against the diminishing results of the other.

Intriguing idea though...

Jeff92se

iTrader: (82)

Heat is what drives the exhaust side turbine

vqman

intriguing idea, but I think the one small, one big turbo like on the Supra is the way to go to get the effect he is looking for...

but that would sound pretty bad a$$...Super Turbo? SCT ?

what would they call it?

-vq

Jeff92se

iTrader: (82)

They did just this in a project MR2. They swapped in a Camry V6 first. Now they are adding a TRD SC and a single turbo. Also using a liquid cooled IC. This month's turbo mag.

Twin chargers or dual charges or something. They are now developing twin turbo chargers. One for the low end and another for the high end. A little different setup than the Supra TT and RX-7 styles

2k2kev

sorry, I thought it was velocity from the exhaust gases that drives that turbine. Can you show me where it says it's the heat that does that? The exhaust gas is hot, no doubt, but I thought it was the speed of the gas ... any URLs?

Jeff92se

iTrader: (82)

Let's say you have xxx amount of molecules. One is very hot and the other set is cold. Which set is going to be able to drive the turbine better? Remember the exhaust is going to be hot when it comes out of the engine's exhaust ports. If you let it cool to let's say ambient, what happens? Consider this statement from him

vqman

that's the way I've always known it to be...the gas that is driving the turbine happens to be hot, but it's the force of it coming out of the combustion chamber that is spinning the turbine.

but I'm no engineer.

-vq

2k2kev

Same here, no automotive engineer. I've studied enough physics and math to understand hotter exhaust would give higher pressure so is probably better, but the main gains of a turbo are from the velocity of the exhaust gases. Also, wouldn't higher pressure in the exhaust side mean more backpressure so the engine would have to work harder to move the exhaust out of the cylinder, thus robbing a little more hp? Let the gas cool to ambient and I bet (no, can't prove it) the 'loss' would be minimal. It's not worth fighting, though.

Jeff92se

iTrader: (82)

What happens when hot gasses moving at a certain speed cools down? Increase or decrease in speed? So yes, it's the velocity that moves the turbines. But what causes the velocity?

You want the exhaust hot. You want the intake charge cool.

jjs

Actually it is the expansion of gases due to the combustion in the cylinder. Heat is a byproduct of the explosions (as are pressure and light), it is not the cause of air flow. The cause is the release of energy during the chemical reaction of 'burning' fuel and air resulting in pressure, light (which we don't see in the chamber), and heat. Heat may contribute to a higher pressure but it does not cause the pressure intially.

2k2kev

Like I said, I know the physics behind it. I guess that's the question, though, what causes the velocity? Pressurize a gas in a tube and it will only increase in velocity if it's already moving. What made it start moving and how much does the temp (really pressure) magnify that?