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[Z06] Laguna Seca - track test and pass sound in 2.5 seconds!

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Old 10-30-2015, 02:46 PM
  #81  
c6hp4fun
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Almost the wrong socket -- the sockets in the white plug have a small opening adjacent to the "real" socket. I had the wire in that. So, yes, it works now. With the jumper wire in place, it's always quiet. With the wire out, and the plugs not plugged back in to the controller, it's always loud. So cheap solution to be able to control it from the driver's seat seems to be: just run a long jumper wire up to a toggle switch on the console. Plug it in as directed. Thanks!!
Old 10-31-2015, 12:25 AM
  #82  
mikymu
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Originally Posted by c6hp4fun
Almost the wrong socket -- the sockets in the white plug have a small opening adjacent to the "real" socket. I had the wire in that. So, yes, it works now. With the jumper wire in place, it's always quiet. With the wire out, and the plugs not plugged back in to the controller, it's always loud. So cheap solution to be able to control it from the driver's seat seems to be: just run a long jumper wire up to a toggle switch on the console. Plug it in as directed. Thanks!!
cool, glad it's working well. remember don't run the car with valve close for long period of time - it may burn a hole through muffler from excessive back pressure
Old 05-09-2016, 12:44 AM
  #83  
c7jim
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Originally Posted by mikymu
Took my Z06 to Laguna Seca for the first time on Saturday's PCA event. Wow! this Z06 is just fantastic! I had 12+ heat cycled Hoosier R6 and I flip it to get some more life and still managed 1:38 in traffic. Car handled all the twist and turns beautifully and I had full confidence even when I lost it a bit coming out of T11.

It was a super hot day and easily over 85F. The coolant temp was much higher at about 230F after 20+ min compare with 210F at Thunderhill. I figure the higher temp must be due to the constant ups and downs and higher elevation changes on the track.

I am sure most of you are aware of the ridiculous sound limit at Laguna Seca. It could be either 90 or 92 db depends on the county rule. Stock Z06 and ZR1 will not pass sound unless you wire the two muffler flaps closed. I have LG headers, 200 cell cats and Akrapovic rear mufflers so it's loud! In the past I had success in passing sound at Laguna Seca with my GT3 RS and also GT3 Cup car with a simple 3.2 seconds fix: http://forums.rennlist.com/rennforum...2-seconds.html

You can also opt for a fancy switch in the car so you can control the muffler flaps at your finger tip: http://www.6speedonline.com/forums/g...inger-tip.html

It turns out that our Z06 and ZR1 have the same exact vacuum solenoid ... well, almost exactly. The GM vacuum solenoid do not have the same vacuum release "pipe" where you can simply cap it and maintain the vacuum and keep the exhaust flap close. Luckily both Porsche and Z vacuum solenoids operate on the same principle. When 12V is supply to the vacuum solenoid it allow vacuum to close the flaps. So, here is how you can supply 12V to the vacuum solenoid on the track:

First, find the vacuum solenoid control module which is located behind the right rear wheel well carpet. It has a larger three wires white plug that tells the control module when the engine RPM pass 3500 to open up the exhaust flap to produce couple extra pony by cutting off the power supply (deliver by the single wire from the black plug) to the vacuum solenoid. The smaller black plug with one wire that supply the 12+V to the vacuum solenoid close the exhaust flaps - hence quiet when RPM is less than 3500.



Now, here is the 2.5 seconds come in for the fix. Get yourself a wire, disconnect the two plugs and connect the wire between the red/white wire on the larger white plug with the single wire on the black plug and you will hear the exhaust flaps close (when engine is not running). Why did I chose our fix to be 2.5 seconds when Porsche GT3 takes 3.2 seconds? Well, it's because our car is faster of course

Don't leave the wire plug in all the time or it will drain the battery. I had mine plug in between sessions and no issue with battery running low and the track sessions are some times 1.5 hours apart. As I understand the "man switch" on the market only allows you to open the exhaust flap and not close it all the time. You can always rig up some sort of switch for the vacuum solenoid so you can go quiet when you needed and revert back to stock when you want it loud and more power at over 3500 RPM



So with this simple mod I only got black flag once at 94.8 db but I was going up T5 next to the sound station as hard as I can and track all the way out to the berm which in itself generate much more tire and exhaust noise hence exceed the sound limit by 2.8 db. I got black first session at stock mode without the 2.5 seconds mod. Stock exhaust should have no issue pass sound with this simple mod

Here is a video of the test run at Laguna and couple pictures with my GT3 buddies ... they adopted me whole heartly



Buddy of mine in his blue Porsche spyder send me video of my Z on the track. I made a split screen movie shown below. This Z06 look super stable under hard acceleration and at fast braking zone on T2







wings wings and more wings

I have heard that running with the flaps closed all the time, especially at wot could hurt the mufflers etc. Did you see any damage to any components while running with the flaps closed all the time?
Old 05-09-2016, 07:32 PM
  #84  
mikymu
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Originally Posted by c7jim
I have heard that running with the flaps closed all the time, especially at wot could hurt the mufflers etc. Did you see any damage to any components while running with the flaps closed all the time?
I have a switch to open the flap so i do not run it with flap closed all the time
Old 05-09-2016, 09:45 PM
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This is pricey if you only use it to control your exhaust, but has some additional benefits.

Old 05-10-2016, 01:19 PM
  #86  
RC000E
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Originally Posted by c7jim
I have heard that running with the flaps closed all the time, especially at wot could hurt the mufflers etc. Did you see any damage to any components while running with the flaps closed all the time?
The C7Z's are incurring damage for sure. Anything from exhaust valve failure (heat damage) to cat damage, etc. They are faced with the same issue at Laguna. A GPS based actuator that opens/closes the valves is the answer.
Old 05-11-2016, 04:45 PM
  #87  
Crossofiron
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Default Well Done!

Looks like a blast and you did not embarrass the Z06 crowd with your driving.

I would like to point out that your LS7 actually help together!!

What year is your car?



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