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Elegant solution to keeping exhaust valves closed on noise limited days

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FogCitySF

2017 GT350R
Has anyone tried this on their 350/R? Saw someone in a FB group say he pulled the exhaust valve relay from the engine compartment fuse box and this kept the valves closed and the 350R was able to pass sound at Laguna Seca (90 db).

EDIT: this "solution" appears to defeat all drive modes, which is less then optimal for more experienced drivers. So far, the Grimspeed resistor plugs with pigtails looks like the most realistic solution.

http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA
 
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Grimspeed makes a plug and play Resistor that I used at Laguna.

You can open the valves so they stay open and plug in the resistor or vice versa.

However after running at Laguna with them closed the car does not like it. I can feel it being smothered.

Especially after driving the car with my Laguna Pipes”.

I’m working on something that everyone has wanted. I should have some results soon.
 

FogCitySF

2017 GT350R
Grimspeed makes a plug and play Resistor that I used at Laguna.

You can open the valves so they stay open and plug in the resistor or vice versa.

However after running at Laguna with them closed the car does not like it. I can feel it being smothered.

Especially after driving the car with my Laguna Pipes”.

I’m working on something that everyone has wanted. I should have some results soon.

Cool...subscribed on the solution (if it's what I think it is)!

Yeah, I'm aware of the grimspeed plugs but just going in the fusebox and removing relay #59 is a lot easier than going under the car and finding the resister connector above each muffler (know some have gotten extensions to make it easier).
 
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Cool...subscribed on the solution (if it's what I think it is)!

Yeah, I'm aware of the grimspeed plugs but just going in the fusebox and removing relay #59 is a lot easier than going under the car and finding the resister connector above each muffler (know some have gotten extensions to make it easier).
Absolutely, it is a PIA to get under there. I will keep you all posted, making this thing is a much much bigger pia.
 
Has anyone tried this on their 350/R? Saw someone in a FB group say he pulled the exhaust valve relay from the engine compartment fuse box and this kept the valves closed and the 350R was able to pass sound at Laguna Seca (90 db).

http://www.fordservicecontent.com/F...&div=f&vFilteringEnabled=False&userMarket=USA

Thanks for posting this, I read that thread as well and was going to post after I tested the #59 fuse. Still need to try it.

I currently just plug the pipes which is quite painless to do but pulling a fuse seems like a more elegant solution.
 

FogCitySF

2017 GT350R
Agree. Would have tried this before posting, but my car is getting a roll bar installed. Unless you are a beginner, I don't think this is an acceptable solution for experienced drivers. So far, the plugs w/pigtails is the best we've got.


Well I tried it, so pulling the #59 fuse defeats the exhaust valves ...and all the drive modes too. IMO this is not an acceptable solution to keeping the car quiet on noise controlled track days.
 
I just put car in track mode then go the exhaust mode and turn off the valves.
Mine didn't open up while on the track.
 

FogCitySF

2017 GT350R
Just as an update, did the Grimspeed plugs and was below 90 db all day at WOT on the uphill straight between 5 and 6 with zero sound issues. The only thing is my installer couldn't figure out what to do with the pigtails (at least wasn't obvious to him).
 
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1,065
Bay Area
Grimspeed makes a plug and play Resistor that I used at Laguna.

You can open the valves so they stay open and plug in the resistor or vice versa.

However after running at Laguna with them closed the car does not like it. I can feel it being smothered.

Especially after driving the car with my Laguna Pipes”.

I’m working on something that everyone has wanted. I should have some results soon.

Have you made the LS pipes yet?
 

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