My 2005 CTT 955 is fast approaching 110,000 miles and the turbos aren't spooling as well as they did just a few months ago.

As I am about to have her tuned, I am seeking advice on whose Diverter Valves to use? I expect to make between 550-600 HP.

I want some new valves made of metal to replace these tired plastic OEM diverters.

Thanks in Advance!

 

I use some forge style bought from Fleabay. They are great quality and pretty standard on VW, Audi and Porsche. Any of the forge style you see on ebay will work. I initially bought some Greddy style blow-off valves to run but could not get them to fit in the stock locations When I get my intercooler setup and hard pipes made I'll put those in. Good luck!

 

I went with EVOMS diverter valves and they work well. Sadly, the secondary cat delete pipes were smaller than my exhaust intakes and took more labor making metal shims. As a result, my bill was $1,000 more than expected! But she seems to run well.

 

What do you mean by your cat delete pipes were smaller than your exhaust intakes??????

$1000 more??? For what??

 

The Leistung pipes were of a smaller diameter and they had some orange sealer or silicone on them from the previous owner. EVOMS said they had to fabricate metal shims so that my exhaust wouldn't leak.

There is a sales front end and other folks, then there is the shop fellow who finalizes the billing.

I was told it would take 3-4 hours of labor but ended up with a bill for 10 hours of labor after being told it really took 13 hours. Plug set was more than quoted previously by two other persons there. And that added 3 hours. I understand 8 hours

I heard from EVOMS that they would be calling me to credit me an adjustment--which I really appreciate. Everything helps as I am a wee bit overdrawn. My medical expenses were REALLY HIGH this month.

All told I spent $1,000 on used parts delivered from a fellow on 6speedonline. Which was an excellent price! For EVOMS intakes with custom screen meshes, Leistung jet coated Secondary Cat by-pass pipes and an IPD Plenum. Then another $3,321.59 for EVOMS software, diverter valves, plugs and a cabin air filter.

Tempe sales tax is a whopping 9.3% on labor as well as parts. I shudder to think what the bill would have been if I didn't get a deal on those parts used. More than $6,000!

Sales at EVOMS told me $750 for their Secondary Cat by-pass pipes but during the final bill the fellow said they charge $950. In all fairness I must mention that EVOMS gave me a discount on their software--which really helped by saving me about $200.

Lesson learned: Get a written estimate first.

My car was the cheapest thing in their shop. Their facilities are huge! Top notch. One cannot do better than going to the source for tuning software. I feel confident that my car is going to run for a long time. EVOMS does it right. I am not over-boosting nor do I feel I am taking any risks. The only difference in maintenance is they recommend changing spark plugs every 20,000 miles (compared to 40,000 miles) and they use a better plug that costs less than dealer and runs a degree cooler. She does run smoother than she did stock!

 

wow man, sorry to hear that. My Leistung Secondaries fit fine and no leaks. I have the copper gasket between the primary and secondary pipes though. I don't see how shims would cost $1k still. Well I'm glad you're back up and running!!

 

They had to fabricate shims that go around the outside diameter of the by-pass pipes.