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Let's talk about cheap exhaust valve mod options!

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Old 01-08-2021, 01:19 AM
  #61  
BritinSF
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I hope you wired them open.
Old 01-08-2021, 01:23 AM
  #62  
sin911
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Originally Posted by bubbledragon
I have had my Spyder for 800 miles now and have not tried to go beyond 5k but frankly I can't tell the difference between PSE on/off so far. As this thread suggests a significant improvement below 4k with plug or wire , being a non DIY and has never done any mods on any cars I want to give valve wiring a try as it seems the lowest risk option.
I had the Carnewal exhaust valve module on my 997.2 GT3 (which is similar to Cargraphic but has Always Open or Always Closed options only) and it did make a difference with the sound for sure! It was not 'night and day' difference but enough to notice it and make the experience much more enjoyable.

Unfortunately my car is still in the shop waiting to get clear bra, so have not had the opportunity to install the Cargraphic module I bought and test it but in my very short drive when I pressed the PSE button it did make a difference in sound.

For the people wiring their exhaust valves open, I'm curious about if this method does any damage to the mechanical arm that shuts and opens the valve over long period of time? I'm assuming this method has been implemented on previous other models as well.
Old 01-08-2021, 01:46 AM
  #63  
RavinS4
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Originally Posted by BritinSF
I hope you wired them open.
When the car is off they are open so unless you are doing them with the car on you should be good.
Old 01-08-2021, 02:24 AM
  #64  
AusGTS4.0
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The valve stems don't move at all when wired firmly. I am no expert but when wired the vacuum will still be applied in the lower rev range but the valves won't move. I asked the same question about possible damage
With the devices (e.g. Cargraphics) that block, stop or divert vacuum (I don't know which), maybe we could ask the same question about those devices.
Any ideas?????

Last edited by AusGTS4.0; 01-08-2021 at 02:32 AM.
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wdr911 (01-08-2021)
Old 01-08-2021, 11:15 AM
  #65  
Westcoast
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Originally Posted by RavinS4
Just wired my valves shut but haven't had a chance to take it for a drive. Pretty easy to do and didn't even have to lift the car or anything. Little sore now though haha. Will let you guys know what I think after a drive.
You do mean open right?
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wdr911 (01-08-2021)
Old 01-08-2021, 11:17 AM
  #66  
RavinS4
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Originally Posted by Westcoast
You do mean open right?
haha yeah I meant open 😂
Old 01-08-2021, 03:48 PM
  #67  
lovetoturn
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Just a thought, but maybe one could wrap a small piece of sheet aluminum around say half of the plunger shaft and bolt it in place. That way the valves would only close part way and allow some gases to pass through the primary pathway while pushing a greater mix through the secondary pathway to better attenuate sound. Have no idea how far to let the valve close though, but it may be a good compromise for both sound and performance. It would certainly cause more mixing of the left and right banks to get more of the flat-6 howl we all seem to be looking for.

Maybe a few tiny hose clamps could work if they could pinch the shaft firmly enough. These go down 6mm (1/4 inch). Not sure if they would fit, but who knows.





Last edited by lovetoturn; 01-08-2021 at 03:58 PM.
Old 01-08-2021, 04:26 PM
  #68  
Jim Rockford
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I would think there's a solution somewhere there where you disconnect the actuator arm and it continues to do its own thing while the flap stays unaffected in the open position. That pin sticking out of the ball looks inviting.
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HooosierDaddy (02-23-2021)
Old 01-08-2021, 08:58 PM
  #69  
lovetoturn
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For now, I have just unplugged the lines and capped them with proper vacuum line parts and zip-tied them to the frame supports. Also capped off the valve actuators to keep all dirt and debris out of them. Much easier when your mechanic does it for you while the car is on the lift.

Just mentioned the possible actuator modifications since it seems like there is either too little or too much sound when it is all or nothing on the valve.
Old 01-08-2021, 09:26 PM
  #70  
DC021
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Originally Posted by lovetoturn
Just a thought, but maybe one could wrap a small piece of sheet aluminum around say half of the plunger shaft and bolt it in place. That way the valves would only close part way and allow some gases to pass through the primary pathway while pushing a greater mix through the secondary pathway to better attenuate sound. Have no idea how far to let the valve close though, but it may be a good compromise for both sound and performance. It would certainly cause more mixing of the left and right banks to get more of the flat-6 howl we all seem to be looking for.

Maybe a few tiny hose clamps could work if they could pinch the shaft firmly enough. These go down 6mm (1/4 inch). Not sure if they would fit, but who knows.
Cut up a piece of rubber hose for a little extra bite and O.D.for the hose clamp to bite onto maybe.
Old 01-09-2021, 10:26 AM
  #71  
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Hi all, just installed a 2 mode cargraphic exhaust valve controller in my 718 GT4. The installation went well. However, upon starting the car, I received a check engine light. Working with the controller, everything seems to be working well. The sport mode on the controller keeps the valves open and on the other mode, the exhaust and the rest of the car feels stock. Considering I continue to have the PSE functionality in normal mode, I think the vaccine tubes are plugged in correctly. Has anyone else experienced similar issues with the valve controller and have thoughts on possible causes ?
Old 01-09-2021, 01:26 PM
  #72  
Westcoast
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^^^ cross postings is very nice...
Old 01-09-2021, 02:34 PM
  #73  
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Went on my first drive with the valves wired open and what a difference. I am still breaking in so haven't gone above 4k so never really heard it with the valves open outside of startup. It sounds way louder than before so pretty happy with this $3 mod for now. Can't wait to get past break in and really hear it. Then will probably try the gutting of the OEM OPF's before deciding on a link pipe.
Old 01-10-2021, 11:39 AM
  #74  
Rennolazine
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Plugged the vacuum lines yesterday... personally liked it better with the valves connected because there is a definite boom 2-3k rpm with the windows up. Its not ear popping drone, but you defo need to drive around it. Windows down its also not enough volume it doesnt have a GT car’s typical street presence. Looking forward to taking all this crap off soon and putting on a proper system
Old 01-19-2021, 12:20 PM
  #75  
andrewdr
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Agree. Thinking about the JCR rear exhaust and leaving the OEM axle pipes. Still trying to figure that one out


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