Yes it's been awhile since I have posted anything on the STS system. I've been doing some tinkering with the exhaust to find the best power to sound ratio. So far, I've learned what everybody already knows, but I just want to confirm it. I've spent hundreds of dollars on playing with different combinations, 2 tips, 4 tips, high flow cats, stock cats, no cats, mufflers with no cats, mufflers in place of stock cats. Since I don't condone to doing anything that would cause a car to be smog illegal, I would like to say that you have to read between the lines and figure things out through your own intrepretation.

A decent sounding system that is a bit loud for my taste, but is more responsive is 4" dia. X 14" long Magnaflow straight through stainless mufflers with a perforated core and stainless packing to resist burnout. These are mounted in front of the H of the exhaust. If you cant understand what I am saying, then don't work on your car. These allow the turbos to spool up much faster then the ceramic core mufflers .

In the rear (after the turbos), baffle inserts are used to retain the STS pipes because of space restrictions. I am running a 4 tip setup because of baffling a 2 tip system has too much back pressure.

The ultimate set-up that has wonderful sound is the Magnaflows after the turbos with no Cats at all or mufflers in place of the cats. The only problem is space restrictions, but the sound is like old school Big-block, deep sound and kick butt attitude.

Also, run dual wastegates.

 

I can see one thing you are coming to understand very clearly.. to have a completely dialed in system.... one has to spend much more money than just the basic kit to get something close to perfection.

VR

 

i know, i like the way my car sounds and just to have it going kinda well im looking at HP tuners, wideband LPE Pump widened rear wheels and nitto tires and a cat delete, plus the options i got with my kit the methanol system and the boost controller. it all adds up fast, but i do love playing

 

Carl,

Now I know why you missed the dinner tonight. You are spending to much time on getting the perfect system.

Lewis

 

"Ain't," that the truth.

Also, I think because we are just getting old, grumpy and particular we want (expect) to have perfection in all areas of our vehicles.
Vs.
Super LARGE cam, no A/C, no heater, rip out interior, noisy...ah youth.

I am glad Carl is working this part.


Brent

 

What did the 2nd wastegate do for you ... performance & soundwise?

Do you have a photo of the Magnaflows ( afterturbo location) you can post here? I'd love to get that 'old school' sound.

 

I clearly understand why you spent as much money on your car as you did.

 

The second wastegate lowered the boost creep I was experiencing. Now I can hold the exact amount of boost I want. With one W/G, I was hitting over 6 psi with springs rated for only 5 psi, after adding the second W/G I can hold it at 5 psi.

Lewishou has pictues of magnaflows on the rear after the turbos. I have the magnaflows in front of the turbos. They are straight through mufflers.

 

You need the second wastegate because you have two turbos. Plain and simple. With the single gate, you get boost creep and you run more boost than your spring is set for. With two, you get the right amount plus it does not creep. Already tested this on the dyno and it works.

Rick

 

I hope you are not using the same mag muffs that lewis and I are using. Those are fiberglass filled and will burn up before the turbos.

Rick

 

Da man is right, it happened on my car.

 

The particular model of Magnaflows I have are stainless packing and they advertise that it resists burnout.

 

What model would that be?

Lewis

 

I explained how to do this, I ran those 4X14 Magnaflows 4 years ago, still have the Catback with those mufflers. Nothing really new, I love the sound of the Magnaflow straight through design.

If you simply Y both of your pipes together after they exit the turbines, into a single you would be fine and have a unique setup. Or just put turn downs with resonators on them. I used to see the Buick GNX's do this when they removed the cats and wanted to tone it down a little.

Click on my sig for the pics. Top right hand corner for the exhaust.