STS Twin Turbo Hits the Dyno!!!

[ZZcamaro]

The STS kit has now been tested both on the road and on the dyno. There have been tons of folks asking about the numbers so here they are:

This thread is intended for informative and discussion purposes only....

I just got some numbers from the guys at STS.

This is base line numbers, and was done with a conservative tune on 91 octane fuel.

Running just under 7psi on an otherwise stock Camaro SS:
541 RWHP and 557 RWTQ
That is up 193 RWHP and 227 RWTQ over their baseline dyno runs!!
This car is making full boost at 3k RPM and drives awesome (straight from STS).

These numbers were on an LS3 which baselined at 348HP. So you have a gain of 193 RWHP!!! That is a heck of an increase!!

These numbers were made with a very conservative tune, and with 91 octane fuel. There will be a little more HP to get from the tune still...

Also there will be upgraded Turbos available with should unlease 20HP more at the same psi levels!! Those have a larger compressor housing and upgraded bearings.

Dyno charts and Videos to be posted soon...The guys at STS have been busy, and the quality of this kit is a testament to their hardwork.

[general23cmp]

Sweet...I'm a little confused about adding 20HP with the same psi just by upgrading turbos?

[Speed74SS]

The baseline numbers seem a little low for an LS3 or maybe it was just the dyno. Either way, those are some great numbers at what looks to be a pretty safe tune and psi. Nice!!!

[ZZcamaro]

Originally Posted by general23cmp

Sweet...I'm a little confused about adding 20HP with the same psi just by upgrading turbos?

Yeah it is weird to understand...I was confused until STS gave me the whole speech...but it has to do with efficiency of the bearings and the larger compressor housing....it also lowers temps more for the intake charge.

[carfansince73]

Wow, great results!

Baseline numbers do see low for an LS3, by around 20hp. 91 octane instead of 93 to blame?

[Stang Stomper]

Originally Posted by general23cmp

Sweet...I'm a little confused about adding 20HP with the same psi just by upgrading turbos?

Think of it like a water hose. A hose that is 1.5" in diameter will flow more water than a hose that is 1" in diameter at the same pressure. Similarly, a larger turbo will flow more air at the same PSI than a smaller turbo, and more air = more fuel = more power.

[ZZcamaro]

Originally Posted by Stang Stomper

Think of it like a water hose. A hose that is 1.5" in diameter will flow more water than a hose that is 1" in diameter at the same pressure. Similarly, a larger turbo will flow more air at the same PSI than a smaller turbo, and more air = more fuel = more power.

Well said.

[general23cmp]

Originally Posted by Stang Stomper

Think of it like a water hose. A hose that is 1.5" in diameter will flow more water than a hose that is 1" in diameter at the same pressure. Similarly, a larger turbo will flow more air at the same PSI than a smaller turbo, and more air = more fuel = more power.

Not sure if I totally agree with this statement...PSI in the manifold is PSI in the manifold. If they are at the same PSI (and temp), the same amount of air is entering the engine. If the larger turbo were supplying more air to the engine as this statement implies, the boost pressure would have to increase. I would say for the above analogy to apply, the pipe would equate to the cubic inches of the motor. Obviously, if the engine is larger and has the same boost, more air is entering it. For two identical engines with slightly different turbos at the same boost (and temp), they are moving essentially the same amount of air.

I do agree that the HP would go up with smaller intake temperatures and thus denser air as ZZ suggested. PV=nRT will apply.

I think this is the reason for the 20HP gain.

[lovesboost]

Originally Posted by general23cmp

Not sure if I totally agree with this statement...PSI in the manifold is PSI in the manifold. If they are at the same PSI (and temp), the same amount of air is entering the engine. If the larger turbo were supplying more air to the engine as this statement implies, the boost pressure would have to increase. I would say for the above analogy to apply, the pipe would equate to the cubic inches of the motor. Obviously, if the engine is larger and has the same boost, more air is entering it. For two identical engines with slightly different turbos at the same boost (and temp), they are moving essentially the same amount of air.

I do agree that the HP would go up with smaller intake temperatures and thus denser air as ZZ suggested. PV=nRT will apply.

I think this is the reason for the 20HP gain.

you can increase volume without increasing boost

[outlawz]

are there pics of this setup and what it looks like underhood???? I know the STS kit mounts in the back so i'd like to see what the kit looks like.... and how much....

[general23cmp]

Originally Posted by lovesboost

you can increase volume without increasing boost

Do you mean engine volume or air volume? Surely you do not mean air volume (considering pressure and temperature are the same).

Yes, turbo A may outflow turbo B at a given pressure; however, you must be dumping more air out somewhere else rather than into the engine for the pressure (boost) and temperature to remain the same if using Turbo A.

Also, it depends on your definition of volume. Hot gases have more volume than cold for a given mass of air, so colder intake temepratures are desired for more air to enter the engine. Less volume is desired if it is achieved by cooling the same amount of air.

Many people mean mass of air when they say volume. The mass of air entering the engine is what is really important.

Bottom line is that if you are feeding an engine of a specific displacement (V), air at a temperature and pressure (boost) of T and P, respectively, then a specific mass of air (n) is being supplied to the engine. R is a constant, and thus PV=nRT. Looking at the equation, if you lower T, then n must increase for P and V to remain the same. Thus more air being supplied to the engine. This equation also shows the relationship that temeprature has on the density of a gas at constant pressure. "n/V" is essentially gas density, so as T goes up or down, n/V must also change inversely for P to remain constant.

I firmly believe that the 20HP increase comes from cooler intake temperatures from a more efficient turbo/cooler if they keep the same boost, providing no injector or computer witchcraft.

I'm not trying to be a jerk. I just want to understand if there is something I am misunderstanding.

[xSSkier874]

As much as would love to type out a long explanation on how you can make more power by increase flow I don't have the time, or care to put it into simple words. This link should help explain it to you.

http://www.grc.nasa.gov/WWW/K-12/airplane/bern.html

[Xanthos]

Nice work STS!

Now get to work on that V6 kit please.
- X

[ZZcamaro]

Originally Posted by outlawz

are there pics of this setup and what it looks like underhood???? I know the STS kit mounts in the back so i'd like to see what the kit looks like.... and how much....

There will be pics posted soon...I will have videos also. They are just working on getting them all taken early next week.