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Post #1 Sat, Jul 15, 5:31 AM

Aych Es Vee
Supercar Messiah - 36014

LOS LOCOS KICK YOUR ASS, LOS LOCOS KICK YOUR FACE, LOS LOCOS KICK YOUR BALLS INTO OUTER SPAAAAAAAACE!

Post #2 Sat, Jul 15, 6:08 AM

steve7467
Supercar Messiah - 2494

Rear mounted turbos are really starting to take off here in the states. The idea behind it is the ease of install, weight transfer to the rear, and keeping the heat away from the engine. With proper exhaust sizing the gains in lag are very minimal. The turbo acts as the muffler (quiet at idle, loud at WOT.)

www.ststurbo.com is the company who has the patent right now, there are alot of homemade kits also.

Edited by steve7467 - Sat, Jul 15, 6:10 AM

Post #3 Sat, Jul 15, 6:15 AM

Aych Es Vee
Supercar Messiah - 36014

okay, thats weird.
I wouldnt like having my turbo so close to the ground

LOS LOCOS KICK YOUR ASS, LOS LOCOS KICK YOUR FACE, LOS LOCOS KICK YOUR BALLS INTO OUTER SPAAAAAAAACE!

Post #4 Sat, Jul 15, 6:35 AM

steve7467
Supercar Messiah - 2494

Quote from Aych Es Vee
okay, thats weird.
I wouldnt like having my turbo so close to the ground

I'm giving it a couple years to see how it handles daily driver abuse. There is a member on the corvetteforum who has a single GT-76 turbo STS kit with a 9.331 at 149.18 run (with slicks) so the power potential is definitely there. I'd imagine the F-body/GTO crowd has something alot faster with a rear mounted system as well.

The only complaint i've heard so far is it is too loud for the street, but custom muffler kits are easily made and noise levels become more acceptable. The oil line/run to the turbos is another concern but so far from what i've seen the kits are reliable.

At least with the C5 kits, the turbos aren't low at all. Here are pics of what the basic STS kits look like:

Edited by steve7467 - Sat, Jul 15, 6:40 AM

Post #5 Sat, Jul 15, 7:00 AM

McLaren_Man
Supercar Messi - 7910

Intake won't be getting much...

http://r.yuwie.com/acesonfire
Concerning Throwing Moo's Kitten Out The Window:
Moo: Thats Harsh
V8Stangman: So?? It's just a cat!
iampingpong: how would you feel if someone threw your kid off a roof and was like "it's only a kid". Moo: he'd write a song about it, called Tears In Heaven.

Post #6 Sat, Jul 15, 7:30 AM

BenFenner
Supercar Messiah - 2556

Quote from McLaren_Man
Intake won't be getting much...

It will get some... But by the time the exhasut has reached the turbo (pronounced turbo lag), it has lost quite a bit of it's energy. It's not the way I'd go, but I'd take it over N/A.

Ben Fenner is secure in his sexual orientation, which makes him a little bit better than most guys.
-CMG

I sincerely hope you're sitting back there saying, "Haha, look at all this wacky shit I'm saying! They really think I'm a pedophile!" rather than actually meaning it.
-bucknutz

Post #7 Sat, Jul 15, 8:55 AM

disord3r
Supercar Messiah - 17572

I hear that the pipe off the turbo to the intake manifold also acts as an intercooler somewhat. And, as steve mentioned, it keeps a little extra heat off the engine bay.

effyoo

Post #8 Sat, Jul 15, 9:09 AM

steve7467
Supercar Messiah - 2494

Quote from BenFenner
It will get some... But by the time the exhasut has reached the turbo (pronounced turbo lag), it has lost quite a bit of it's energy. It's not the way I'd go, but I'd take it over N/A.

According to STS, this is where exhaust size matters. They specificaly made their exhaust to prevent the lag. Per the FAQ's on their site:

"With the turbo so far back, don't you get a lot of turbo lag?

No, our turbochargers are sized to operate at this remote location. Just like any turbocharger, once the turbo is up to temperature and in the rpm range for which it was designed to operate. The boost comes on hard and fast. All of our systems will produce full boost below 3000 rpm.
If you were to take a conventional turbo and place it at the rear, you would have lots of lag and consequently, our turbo wouldn't work properly if mounted up front."

http://www.ststurbo.com/f_a_q

For the intake not getting air, there are a few 800 RWHP+ vettes that have these kits so I would say they are doing fine. STS states because of the rear mounting, they actually getting cooler air than a front mount setup. From what i've seen over the past few months, front mounted turbos still make more low/mid HP than this kit. But this kit still outperforms SC'd kits on the low/mid range(with similar peak HP.) Too lazy to get charts, but head over the the corvetteforum and search in their forced induction/nitrous section. Also this kit/concept is still new in terms of popularity, so I'm sure there will be alot of improvments and different turbo combos that give different power curves. Time will tell.

Edited by steve7467 - Sat, Jul 15, 9:21 AM

Post #9 Sat, Jul 15, 10:21 AM

sixspeedfirebird
Supercar Messiah - 21052

I've heard of a couple of F-body guys having their turbos stolen right from under the car, and other's who have beat and banged em up pretty badly. But it seems like if you coulod find a way to protect it, they're a cheap, big power mod.

fivespeedturbogolf
cvtboringscoobie
F50 > F40

Post #10 Sat, Jul 15, 10:30 AM

SaabJohan
Supercar Messiah - 2112

Obviously the guys at STS don't know much about thermodynamics and turbocharging. The energy (temperature*massflow) that reaches the turbine is what powers the compressor; hence the transient response and boost pressure possible is depending on the energy that reaches the turbine inlet. You can't just design a turbo to make something of nothing.
The large volume of the exhaust/induction system will also increase lag.

Lower exhaust gas temperature will not reduce charge air temperature.

There are no US patents in the name of STS Turbo Systems, Squires Turbo Systems or Rick Squires.

Mounting the turbo a few meters behing is also nothing new; it was used in some WW2 airplanes due to several reasons, mainly packaging and weight distribution. But unlike modern turbochargers the turbochargers of the 1940:ies could not withstand such high temperatures. In an airplane transient response and low end power isn't really needed either. In airplanes turbochargers also got an altitude compensating effect, and increased altitude means increased turbine power due to the atmosphere pressure loss.

Turbines in the exhaust stream on piston engines always act as mufflers.

Post #11 Sat, Jul 15, 11:40 AM

steve7467
Supercar Messiah - 2494

Quote from SaabJohan
Obviously the guys at STS don't know much about thermodynamics and turbocharging. The energy (temperature*massflow) that reaches the turbine is what powers the compressor; hence the transient response and boost pressure possible is depending on the energy that reaches the turbine inlet. You can't just design a turbo to make something of nothing.
The large volume of the exhaust/induction system will also increase lag.

Lower exhaust gas temperature will not reduce charge air temperature.

There are no US patents in the name of STS Turbo Systems, Squires Turbo Systems or Rick Squires.

Mounting the turbo a few meters behing is also nothing new; it was used in some WW2 airplanes due to several reasons, mainly packaging and weight distribution. But unlike modern turbochargers the turbochargers of the 1940:ies could not withstand such high temperatures. In an airplane transient response and low end power isn't really needed either. In airplanes turbochargers also got an altitude compensating effect, and increased altitude means increased turbine power due to the atmosphere pressure loss.

Turbines in the exhaust stream on piston engines always act as mufflers.

The patent has been mentioned numerous times on various sites in the past (which I was going by/assuming.) Maybe it's pending? Maybe it's a common misunderstanding. I have no clue. On thier site they do state: "Founded by Rick Squires in 2003 and located in Orem, Utah, STS is revolutionizing the aftermarket performance industry with patented remote mounted turbo systems for cars, trucks and SUVs."

I'm not a physics expert, all I can say this thier system works and works well. Further in the FAQ they explain things a little better:

"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?

No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.

Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".

Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."

Not agreeing or disagreeing with you, just clarifying.

Edited by steve7467 - Sat, Jul 15, 11:41 AM

Post #12 Sat, Jul 15, 10:48 PM

disord3r
Supercar Messiah - 17572

Also, it seems almost too easy for some debris to fly up in there and snag an oil line or something like that. There's a bit more exposure in this system from what I can see.

effyoo

Post #13 Sun, Jul 16, 6:40 PM

SaabJohan
Supercar Messiah - 2112

Quote from steve7467
The patent has been mentioned numerous times on various sites in the past (which I was going by/assuming.) Maybe it's pending? Maybe it's a common misunderstanding. I have no clue. On thier site they do state: "Founded by Rick Squires in 2003 and located in Orem, Utah, STS is revolutionizing the aftermarket performance industry with patented remote mounted turbo systems for cars, trucks and SUVs."

I'm not a physics expert, all I can say this thier system works and works well. Further in the FAQ they explain things a little better:

"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?

No, heat doesn't create velocity. Heat creates volume. If you look at any of the physics laws for gasses, you will find that pressure and volume and heat are related. PV=NRT is a popular one, The V isn't for velocity, it is for Volume.
The turbine housing is what creates the velocity. The scrolling design that reduces the volume of the exhaust chamber as it scrolls around causes the gasses to have to increase in velocity and pressure to maintain the same flow rate.

Hotter gasses have more volume, thus requiring a higher A/R which in effect means that it starts at say 3" and scrolls down to approximately 1". Lower temperature gasses are denser and have less volume, so they require a lower A/R housing which would start at the same 3" volume, as the turbine housings use standard flanges, and scroll down to say 3/4".

Now if you were to reverse the housings in application, the conventional turbo would spool up extremely quick, at say around 1500 rpm but would cause too much backpressure at higher rpms because the higher volume of gas couldn't squeeze through the 3/4" hole without requiring a lot of pressure to force it through. On the reverse side, the remote mounted turbo with its cooler denser gasses, wouldn't spool up till say around 4000 rpms but once spooled up would make efficient power because it doesn't require hardly any backpressure to push the lower volume of gas through the larger 1" hole."

Not agreeing or disagreeing with you, just clarifying.

All US patents can be found here: http://www.uspto.gov/
Well, there are some exceptions, patents held by for example NSA are not always availible.

In order to get a patent it must meet certain standards, anyone can apply for one if you can afford it, but to get one that is a different issue. I don't see how their turbo system should meet the demand that you put on a patent.

"Doesn't heat create the velocity in the exhaust gasses to spool the turbo?"

Correct answer: Yes, heat is turned into kinetic energy in the turbine and turbine nozzle. The specific work extracted by a turbine is given by the Euler turbomachine equation

W = U1*C1 - U2*C2

where

U = blade velocity
C = gas velocity
1 refers to the inlet
2 refers to the outlet

If we assume an ideal nozzle

C1 = sqrt(2*Cp*T1[1-(1/er)^((k-1)/k)]

where

Cp = specific heat of the gas
T1 = gas temperature at inlet
er = expansion ratio
k = ratio of specific heats

But W isn't only equal to U1*C1 - U2*C2, but it can also be written as

W = dh = (Cp1*T1)*(Cp2*T2)

The power output of the turbine is written as

P = W*m' = dh*m'

where

m' = massflow of gas

Furthermore, the maximum efficiency of any heat engine is given by the Carnot cycle

n = 1 - Tc/Th

Where

c refers to cold
h refers to hot

If we compare turbine inlet temperatures of 1250 K vs. 850 K where the cold source is 273 K the maximum efficiencies are 78 vs. 68%.

Lower turbine inlet temperature means that the energy availible to the turbine will be lower, thus will the power output of the turbine be lower. Also, turbine efficiency will be lower, reducing turbine power output even more.

The pulsing behaviour of an engine also affect exhaust scavenging and energy losses, in general one can say that a small manifold volume before the turbine has advantages.

If their system was tested against a well engineered turbo system they would have lost big time, especielly at tests of transient response and low end torque. But since no comparisons are availible it's easy for them to claim that it works well. It would also be difficult to reach high boost pressures with this type of system, with a higher boost pressure the turbine must extract more specific work since the power requirements of the compressor goes up while massflow doesn't.

Post #14 Sun, Jul 16, 8:49 PM

RLQ
CAUTION - 58501

I think would suck if you go over a huge bump in the road.

I don't give a crap about whales so go and hug a tree.

Post #15 Sun, Jul 16, 9:39 PM

steve7467
Supercar Messiah - 2494

SaabJohan,

I do not have the physics knowledge for a true discussion/debate with you. All I can say is 1) their system works, whether overall efficiency is lower than front mounted turbos or not (they have 900+ RWHP kits with LSx motors, and as mentioned earlier they do better than SC'd cars with similar peak hp(demonstrating their efficiency is acceptable overall) 2)Their remote turbo systems are the 2004 Best High Performance Product award at the SEMA show. We can both agree SEMA is a reputable organization and have people smarter than me and just as smart as you (your past posts prove you know your stuff.) Therefore we both can agree that their products aren't some gimmick. Like all power adder options, they have their strengths and weaknesses. Remote turbo's are an excellent performance for $$ mod (efficiency isn't everything.) I'm sure if you were care enough about their kit specs, you could conclude with your equations they are legit.

SEMA award: http://www.ststurbo.com/sema_2004

On the patent info:

http://www.ststurbo.com/patent

Squires Turbo Systems, Inc. Awarded Patent

On June 8th, 2004 Squires Turbo Systems, Inc. was awarded a patent on its remote turbo system.

U.S. Patent 6,745,568 "Turbo System and Method of Installing"

The key areas of the patent include the remote location of the turbo, the oiling system and the passive charge intercooling.

"We are honored to receive this patent and excited about the future of remote-mounted turbocharging. We hope that this technology will allow many more people to enjoy the increased power and efficiency of turbocharging their vehicles."

Rick Squires - Founder of Squires Turbo Systems, Inc.

To learn more about how this system works, please visit www.ststurbo.com and click on "How it works" or call toll free 1-866-WE-TURBO.

Add: Per your provided URL, include patent 6745568 in their search and they do have a patent.

Edited by steve7467 - Mon, Jul 17, 12:54 AM

Post #16 Sun, Jul 16, 9:53 PM

V8Z
Supercar Messi - 5309

Obviously every major magazine that has done a test with them has been payed off.

Post #17 Mon, Jul 17, 1:56 PM

Blackwood
Supercar Messiah - 2280

Quote from V8Z
Obviously every major magazine that has done a test with them has been payed off.

He didn't say it doesn't work. He said it's not ideal. You have to wait longer for exhaust heat to get maximum boost. But trade that off against ease of install/maintenance.

what

Post #18 Mon, Jul 17, 2:00 PM

SaabJohan
Supercar Messiah - 2112

Quote from V8Z
Obviously every major magazine that has done a test with them has been payed off.

Then show me a test where someone with knowledge about turbo systems have done a comparison between their system and a system with a conventional turbo placement.

The graph to the right show torque output with various turbine housings and manifold designs (manifold volumes).

M1 is a compact 4-2-1 manifold, M2 is a tuned 4-2-1 manifold and M3 is a damping volume of 5 litres (but still the turbo is close to the engine). Test conducted on a Saab 2.3 litre engine. M1 is similar in design to the stock Saab manifold.
T1-T3 are different turbine housings. It can be noted that the effect of the manifold used is greater than the selection of turbine housing.

The graph to the left show approx. heat loss from the different types of manifolds.

Edited by SaabJohan - Mon, Jul 17, 2:03 PM

Post #19 Mon, Jul 17, 3:46 PM

stiffstuffW
Supercar Messi - 4699

Heck of a lot of piping...

Post #20 Mon, Jul 17, 5:17 PM

norco123
Supercar Messi - 3754

i kinda like this setup, its ideal if you have a small car + want a HUGE turbo but cant fit it in the engine bay.

do not want.

Post #21 Tue, Jul 18, 8:05 AM

Monkey
Supercar Messiah - 4963

These turbo systems work, but as SaabJohan has already pointed out, a conventional setup would perform better. Not just from the turbine side, but from the compressor side of things as well. All the extra boost piping means increased friction which means that less of the pressure made at the compressor outlet reaches the manifold when compared to the pressure drop through a conventional system.

Isaiah 26:4 :: Ephesians 2:8-10 :: Hebrews 3:12-14 :: "when the rich wage war it's the poor who die"

Post #22 Tue, Jul 18, 9:13 AM

Blackwood
Supercar Messiah - 2280

Quote from Monkey
These turbo systems work, but as SaabJohan has already pointed out, a conventional setup would perform better. Not just from the turbine side, but from the compressor side of things as well. All the extra boost piping means increased friction which means that less of the pressure made at the compressor outlet reaches the manifold when compared to the pressure drop through a conventional system.

Let's hear it for the Moody Friction Factor.

Hip hip... oh never mind.

what

Post #23 Tue, Jul 18, 9:26 AM

Monkey
Supercar Messiah - 4963

Quote from Blackwood
Let's hear it for the Moody Friction Factor.

Hip hip... oh never mind.

We love the Moody Diagram!

Actually, my "Mechanical Engineering Reference Manual for the P.E. Exam" by Lindeburg has the Moody friction factors tabulated, so it's a little more accurate than trying to read the numbers off the chart. Pretty cool.... if you're a nerd like me.