PathfinderGTS

Hey y'all, got my 991.2 GTS and installed an FVD tune (which I love), and the car ran amazing for about two weeks... until it blew a diverter valve (car still had the original OEM diverter valves, which I've read can have issues with tunes), so I replaced the OEM diverter valves with Flat 6/EVOMS diverter valves... which lasted all of two days before another blown diverter valve. Doing some research it seems I'm not the only one who's had issues with the EVOMS version. That being said, anyone have an experience with swapping the diverter valves for ones that a bit more robust? APR R1? FVD? Etc.?

Out of curiosity, @4 Point 0 which diverter valves are you currently using on your build?

Thanks in advance for any help, everyone!

bighoward503

What was the indication you had a blown diverter valve? I’m thinking of getting ahead of this and replacing mine as well as I’m running the Softronics tune.

PathfinderGTS

At wide open throttle watch your boost gauge. You'll see it hit higher psi (like 17-18 psi) and suddenly drop boost to 11-13 psi and just keep rapidly cycling back and forth like that (18 to 13 to 18 to 14 to 17 to 11 to 18, etc.) until you let off the throttle. You'll also notice it doesn't dump boost as quickly when you let off the throttle or shift. That's what I've seen on my car, at least.

Tier1Terrier

I have the Softronic tune with the Flat Six EVOMS diverter valves and no issues. I have to say that I'm not expertly familiar with diagnosing problem with the diverter valves but I do wonder if the issue you are describing is a problem with the diverter valve or the tune.

Also, My understanding is that upgrading the DVs for your typical OTS or stage 1 type tune is really no necessary but serves more to add piece of mind. While it is true, based on what I've read, that the DVs can and occasionally fail, it's not something you would expect to see happen until you have much higher boost pressures or perhaps running a tuned car hard and for prolonged periods of time. I think the fact that you've "blown" two sets of diverter valves, one of them being known to be of very high quality suggests to me that either (a) perhaps the diverter valves have never blown, (b) there may be an issue/glitch with the software/ECU tune, (c) that the issue may be with your gauge or sensor, or (d) a hose somewhere has come loose. It's just hard for me to imagine that you've had two sets of diverter valves fail because the diverter valves were the problem, assuming they've even failed at all.

I fully expect someone much smarter than me to come around and correct me or offer some other helpful information.

PathfinderGTS

Honestly, I had a similar thought, but then realized that software issue wouldn't work fine for days or weeks then suddenly stop working. It would raise it's ugly head every time you went to WOT. If the hose had come loose it would also (from what I've read) cause an vacuum error to show up, and so far nothing there. If a vacuum line had popped loose (again, from what I've read) the PSE wouldn't function properly and you'd get no boost (and I both have boost up until about 18psi and the PSE is functioning properly).

john4fun

i have the flat 6 diverter vales on my GTS with a lichfield tune , and can honestly say i have had no problems

devtec

APR R1 diverter valves with Litchfield tune and no problems here.

stercrazy

I'm two days and 50 miles into the APR R1 diverter valves, hardly enough to provide any quality feedback other than to say they haven't catastrophically failed.

One note, I installed these R1's along with the AMS 991.2 intercooler system, APR K04.3 turbo kit, and APR stage 3 tune. The R1's are physically wider than stock and are smashed between the larger than stock AMS carbon fiber outlet duct and the factory engine heat shield that sits behind the intercooler cage. There's potential for some rattling noise or surface damage to the AMS outlet ducts on account of them resting against the R1's.

Pakman996-991.2

I have the Flat6 EVOMS dv’s with Tial inlet tubes, GTS turbos and APR stage 3 tune. No issues to report so far and I drive it hard.

Blowing through 2 sets of DV’s seems very unusual. I would have your indie look into it for sure. Very interested to know what’s going on.

Some guys are running the Turbosmart Kompact DV’s on 650 HP setups with no issues. I originally wanted these but couldn’t wait for restock. Here’s the link: https://www.turbosmart.com/product/kompact-plumb-back-25mm/

Nathan_

Found a sticky Flat6 valve on my car which seems like it may have been the source of my intermittent low boost, replaced with TurboSmart ones so fingers crossed it doesn’t come back.

enzotcat

I have the APR R1 diverter valves along with GTS turbos + tune. No issues and I’ve done some pretty hard track driving with it.

4 Point 0

I have TurboSmart ones. Sorry, I don’t know the model. I did them years ago as a precaution and was shocked to learn that one of the stock ones had failed.

Stock ones will fail all by themself, even on a stock car. It’s because its a very poor design. Boost put pressure on the spring to open. It eventually wins. Whereas after market versions, boost keeps them closed. They open under vacuum. Far more sensible. .

Pb Pedis

Nobody mentioned Forge so I will - holding 29 psi and 850+ HP. Highly recommend.

https://www.forgemotorsport.com/Pors...uct--1367.html

DR911s

Which Forge brand diverter valve[s] did you choose? I have a 2017 C2S, and I believe that the OEM diverter valves on my car are 25mm inlet and outlet, and am guessing that the vacuum hose nipple is 6mm.

Revsportz

I know this is old thread but hoping you can answer. Did you used the Turbosmart kompact plumb back diverter (ts-0203-12222)? If you did was the spring the came with it enough for a GTS stage 3, I believe it’s a green spring rated at -15 inHG. Thanks