Hi guys. I need some information and comments on Kevin's stage 1 and stage 2 turbo upgrade. Wich is the difference between both? I need to replace mine and want the best option. Also what else do I need to add with each set up, IC, LWFW, etc. Any sugestion or comment?

Regards

 

You'll need to get the exact data from Kevin, but in my research, the stage 2 is a small price increase over the stage 1, and should be a noticeable performance upgrade. Your Protomotive ECU may be able to handle the stage 2 without any further work. A large IC is debatable... some guys think they help, others think not, It probably depends on how you'll use the car. I think a big IC helps in race conditions where you want to avoid heat soak. LWFW is a nice upgrade, fully independent of the turbo upgrade. I'd sure look into a large aux oil cooler, suspension work, and perhaps the billet divertors.

 

Steve,

OK, as a newbie to the 993tt, I will bite...

What is a billet diverter

 

Aluminium aftermarket diverter valve.

 

Tom
The factory diverter valve is plastic. A billet diverter would be carved from a solid piece of aluminum.

 

In case those two explanations aren't sufficient, a divertor valve is also known as a "blow-off" valve. It will allow excess boost to be bled off. If the crappy plastic ones start leaking, it will start blowing off normal boost, robbing HP. Replacing them with billet valves is a precautionary measure. Just a good idea.

 

Steve, I think blow-off valves vent to atmosphere (think 964Turbo and that pssssshtt noise) and diverter valves vent back to the pressurized side of the system.

 

Scott, you're "more" correct than Steve, but they both bleed compressor side pressure so that back pressure doesnt rob compressor side momentum and to safeguard against damage. The difference is where they "blow" that extra pressure as you pointed out.

Tom, check out this site for more infor billet DV's:

http://www.evoms.com/porsche%20ec%20art%20test.htm

I bought my set from here. No other affiliation other than as a customer.

 

A part which tuners seem to like fitting to make a bit of extra profit claiming that the stock ones are crap and leak. (said based on mine still running the original stock ones after many hardish miles at some highish boost levels )

 

TB, perhaps that is the reason you didnt get all the horses from the stage3's

but serious, how can one exactly say if they are gone? Any simple testing?

 

my motor is stock and my car was not making full boost. i had my blowoff valves done and it did make a difference. Billet valves are cheap, but it is 3-4 hours of labor to get them in.

 

Nice Q Stummle. I'm all ears to learn.

 

I'm replacing mine because I thought someone said that if the stock ones fail, there is a chance (albeit slight) the diaphragm can go through your turbo causing damage.

I understand when they have failed, they make a funny honking sound when you get off the gas.

Greg H.

 

Folks, Bypass Valves are designed to so that when you shift or brake, the result is that your throttle-body slams shut.. The turbochargers are still spinning and making air.. The BOV valve has a spring rated at a certain boost/pressure level. The pressure that is built up due to the throttle-body pushes against the spring loaded valve or diaphram and is bypassed NOT to atmosphere.. But directly to the intake manifold. The air is recycled into your turbochargers, compressed and routed to your intercooler and into your plenum... The factory bypass is made of plastic and the diaphram can and does tear.. It will then pass into the intake track and get recycled into the turbocharger compressor wheel.. You will launch a set of compressor wheels... In TB's case he's a lucky guy...

A word of caution.. In high boost application, the Bypass valves are forced due to extreme boost conditions.. Many supplies springs will not hold pass 1.3bars... Thus we start to bleed boost by error...

 

If the Porsche BPV are anything like the Audi ones, I'll probably be replacing mine, too. On my S4, the stock ones (less than 10k miles) were sticking so I replaced them with Forge units. The only thing to keep in mind is that these things do require some maintenance, they need to be regreased once in a while. Wasn't a big deal on the S4 because they were easy to get to, but on the 993TT, that may be a pain.