Hello SmokinVette enthusiasts! This is our product review for the STS twin turbo system. When it comes to turbo systems for the Corvette there aren’t a whole lot of them to choose from. There was one thing that we had heard a lot of when we started looking at the STS system and that was the so called turbo lag. We were out to see what all this talk was about!

When we first got the STS Turbo system delivered I must say that at first glance it was quite overwhelming. There seemed to be a thousand parts and thousand feet of wiring! At any rate, we separated all the parts and made sure that everything was accounted for. Now it was time to start the install.

Before we could start installing the STS twin turbo system we had to bring the compression back down on the engine. It was at 11.7 to 1 and we needed to get it down as far as possible. We ended up getting it down to just a little under 10 to 1 and we felt that this was a good spot to be. We also put a nice turbo cam in the motor while we were at it.

One of the first things that I would like to say is that I had never installed a turbo system before and I knew that I was going to need a lot of direction. I must have talked to the people over at STS a handful times per day just to make sure that I wasn’t doing anything wrong! The instruction booklet that STS sends with their system is very informative and very easy to follow which was a breath of fresh air when installing something of this nature.

I am not going to go over every step of the install because STS already has a fantastic instruction booklet and a superb support line for all questions. What I will do though is talk about how nicely the system went in and any complications that I ran into. All the pipes and actually everything else to be quite honest, were engineered to perfection in my opinion. I say this because there were no pieces that were put on that needed to be “worked” to get on. All the pipes went on with ease. The only pipes that I had a “fun” time with were the rocker panel pipes, but I just removed the rotors and the rocker pipe went in pretty easy with just a little wiggling.

I did all the wire routing in about a day and the piping was put in the next day along with the intercooler. Surprisingly the intercooler went in very easy as I have heard that a lot of other intercoolers are very tough to install. Once again this was a testament to the design. The third day was all the detail kind of stuff, tightening everything, hooking up all the wires, zip tying and so on. So that was about three days that it took to get the whole system in! Not bad at all considering that I am not an expert!!

Once it was all together we started the car up just to make sure that everything was running alright. We had the timing pulled way back seeing that we didn’t have a meth kit installed yet and wanted to stay safe even though we were only running 6-7 lbs of boost. We ran the car for a little bit, came in and tightened up all the clamps and then did this again. This is definitely needed as each time the clamps did need tightening. We then put everything else back on and that is where we are right now. We are going to be putting a boost controller and a meth kit on and from here we will give it a good tune.

With that said, this STS twin turbo system was a pleasure to put on as it was just like a good puzzle in that once you know where the pieces go, you just put them there and it goes right together! So if you are in the market for a turbo system or just want a TT system, the STS system should be first on your list for several reasons. They are already known to be easier to install than any other system out there, the heat factor or rather the lack of heat is a huge positive seeing that the turbos are in the rear of the car. Then probably one of the biggest reasons to go with an STS system is the customer service. As I stated, I called a half dozen times each day and I got a live person on the phone each time, thanks Chris!

We give STS twin turbo a HUGE smokin two thumbs up!!!!!
Stay tuned for the dyno results when the boost controller and the meth kit have been installed. At that time we will be able to address the so called “lag” problem!:burnout:

that is pretty cool, lets hear what she does when you put the boost controller and meth kit on!:thumbsup3:

Nice review, when can we see some photos :drool5:

I have been hearing alot of good things about the STS system lately. I think they are now the Kings of the TT for the Vettes.

So, how much RWHP and torque did she end up making?

:yoda:
I had an STS turbo system on my Dodge Ram a while back and things didn't go so well.:loser:
I notice they still don't have a reference for the setup on their web site.:abduct:

Anyway, while being 100% sure mine was set up to the letter, I lost a total of 3 turbos due to oil starvation or over-pressure blowing the seals.

The over-pressure was due to their oil pump failing. Seals blew and the turbo melted.

The two starvations, I figured later, were due to the computer trying to keep up and the engine either chugging or stalling completely with the turbo spinning at high RPM. No oil + turbo spinning at high RPM = Turbo Failure.

I followed all of their instructions adding OP gauges at the engine and turbo but never got a fix for the starvation problem. My guess, in hindsight, is that a Porsche style oil reservoir above the turbo might do the trick.

To their credit, STS did replace the turbos and gave lots of advice.

Unfortunately, my pistons ended up in the oilpan and STS stopped being of any help.

Just a word of caution for your consideration;

What will happen if your car stalls for any reason when the turbos are spinning? Having lost 3 turbos to this very issue, without any failsafe, I think this is a major flaw in the design.
:soapbox:

I also have to report that my pistons ended up in my oilpan even though I verified that my system was installed to the letter of the instruction manual.
Kind of like cigarettes, when used as directed, you die.

If and when it happens to you, you can expect help when :pigsfly:

The oiling problems are what caused the turbos to fail 3 times.

STS told me that my engine failed due to running too lean.

In my own defense, I had an Air/Fuel ratio gauge that never showed a lean condition. And, each of the three times the turbo failed I went step by step through the manual to be 100% certain the systems was installed properly. It was. :doh:

:yoda:
I had an STS turbo system on my Dodge Ram a while back and things didn't go so well.:loser:
I notice they still don't have a reference for the setup on their web site.:abduct:

Anyway, while being 100% sure mine was set up to the letter, I lost a total of 3 turbos due to oil starvation or over-pressure blowing the seals.

The over-pressure was due to their oil pump failing. Seals blew and the turbo melted.

The two starvations, I figured later, were due to the computer trying to keep up and the engine either chugging or stalling completely with the turbo spinning at high RPM. No oil + turbo spinning at high RPM = Turbo Failure.

I followed all of their instructions adding OP gauges at the engine and turbo but never got a fix for the starvation problem. My guess, in hindsight, is that a Porsche style oil reservoir above the turbo might do the trick.

To their credit, STS did replace the turbos and gave lots of advice.

Unfortunately, my pistons ended up in the oilpan and STS stopped being of any help.



Just a word of caution for your consideration;

What will happen if your car stalls for any reason when the turbos are spinning? Having lost 3 turbos to this very issue, without any failsafe, I think this is a major flaw in the design.
:soapbox:

I also have to report that my pistons ended up in my oilpan even though I verified that my system was installed to the letter of the instruction manual.
Kind of like cigarettes, when used as directed, you die.

If and when it happens to you, you can expect help when :pigsfly:

i had the exact same issue with my 2001 c5 vette in fact i just lost my motor a week ago after only having the kit on for 4 months with only 5lbs of boost not only did i lose my motor from the kit but through the whole process sts customer support was horrible and even thought they promised me they would make things right they failed to do so. now im 15,000$ deep in a car that was supposed to be fast but insted goes no wear if i could do it all over again i would save my money and get a z06. ohh side note my car only has 30,000 miles on it so there is no excuse for what happened and the fact that my car did blow up dosnt surprise me after having multiple wrong parts sent to me. ohh and dont forget the wrong tune sent 5 times. and they say they have done 1000's of vettes just ask around to any personal sts vehicle owner they will tell you the truth about the company and their support. the excuse i got from sts is that they have gotten so busy that they cant keep up which means that once u perchase the kit you get kicked to the curb with a horrible kit that has 1000's of issues and trust me you will have at least 20000$ in your vehicle before you get it right and you may end up with a new motor as well. also even after sts claims its amazing hp per pound of boost, i dynoed 410hp at the rear wheels at 5lbs of boost no wear near what they claim they are simply liars.