[Z06] Laguna Seca - track test and pass sound in 2.5 seconds!
06-18-2012, 04:16 AM
#1
Pro
Thread Starter
Laguna Seca - track test and pass sound in 2.5 seconds!
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
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
Last edited by mikymu; 06-24-2012 at 09:44 AM.
06-18-2012, 11:02 AM
#7
Race Director
Looks like loads of fun!
06-18-2012, 11:02 AM
#8
Pro
Thread Starter
Cheers guys. Glad you enjoy the post. This simple sound mod will help you pass sound at most tracks including Laguna Seca. There is a corvette challange coming up at end of June so these guys need to pass sound at Laguna Seca or they are going to have a horrible weekend
06-18-2012, 02:16 PM
#10
V10LEE
I was there. Your car looked good
That was the first time running at a Porsche Club event. First time with my new Z out .With that being said,I also ran into some of the same problems of other ppl not pointing me by. Then I get accused for it when traffic occurs. Never had these problems before running at other track events by other clubs/organization.
Yeah the sound restrictions suck. That's why I just leave all my cars stock.
That was the first time running at a Porsche Club event. First time with my new Z out .With that being said,I also ran into some of the same problems of other ppl not pointing me by. Then I get accused for it when traffic occurs. Never had these problems before running at other track events by other clubs/organization.
Yeah the sound restrictions suck. That's why I just leave all my cars stock.
06-18-2012, 04:22 PM
#11
Team Owner
I will put a link to this thread in the Corvette Challenge event thread for LS
DH
06-18-2012, 09:08 PM
#13
Pro
Thread Starter
I was there. Your car looked good
That was the first time running at a Porsche Club event. First time with my new Z out .With that being said,I also ran into some of the same problems of other ppl not pointing me by. Then I get accused for it when traffic occurs. Never had these problems before running at other track events by other clubs/organization.
Yeah the sound restrictions suck. That's why I just leave all my cars stock.
That was the first time running at a Porsche Club event. First time with my new Z out .With that being said,I also ran into some of the same problems of other ppl not pointing me by. Then I get accused for it when traffic occurs. Never had these problems before running at other track events by other clubs/organization.
Yeah the sound restrictions suck. That's why I just leave all my cars stock.
Thanks!
06-19-2012, 09:27 PM
#15
Pro
Thread Starter
Thanks and glad you enjoy the video. I have a Sony camcorder and it's mounted on the roll bar. Gopro is OK for certain situation but video quality is not good enough
06-19-2012, 11:03 PM
#16
Race Director
06-20-2012, 01:06 AM
#17
Team Owner
The best place I think to mount the GoPro is right behind the rear view mirror. Here is video I took from my first time to LS 1 year ago
DH
06-20-2012, 05:23 AM
#18
Burning Brakes
i meant to ask you
what is the name of the kind of tranny you have in your cup car?
something link? I can't remember. Does it use a clutch pedal, or is it like an F1 in a ferrari with no actual clutch pedal? It doesn't auto blip the throttle does it?
what is the name of the kind of tranny you have in your cup car?
something link? I can't remember. Does it use a clutch pedal, or is it like an F1 in a ferrari with no actual clutch pedal? It doesn't auto blip the throttle does it?
06-20-2012, 10:54 AM
#19
Race Director
That came out great- and nice laps too!
I had no idea that you'd been to LS. My Dad's house is about 3 miles from the front gate, so I've been there a lot over the years.So, how did you attach the Go-Pro? I couldn't see a way to use the hinged pieces and suction cup to make it work on the steep angle of the glass.
06-20-2012, 11:13 AM
#20
Team Owner
I would love to go on this track one day.