When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
i cant comment on laguna specifically, but at infineon we sit right next to the sound person, and we've noticed that a pack of cars together is louder than one car by itself.
or to put it another way, YOU and I might pass sound seperately, but if we're right next to each other probably not.
i think the limit at infineon is 103DB, and they wont do anything if you go by once at 104ish if you go by once at 110, they will flag you, or of you go by twice at 105-106.
sounder meter there is turn 12 drivers left, its really close to the flagger there.
Guys i don't understand this. Last year i had a 13b-rew BP engine with a T04Z and a 4" exhaust and my noise was 96db at 4500 rpm. And it was even quieter on the track. Some ppl asked what i had done to make it quiet. All i said i had bought a Coast Fabrication muffler for my car. And that made so much diffrence.
Try out a coast fabrication muffler in the middle and you should get the exhaust so much more quiet. you can even put one in the back for it to be even more quiet.
But they do burn up rather fast. Wich is why they are rebuildable. Well fast depends on the use. But i think they will last max 10 track days at the time.
Guys i don't understand this. Last year i had a 13b-rew BP engine with a T04Z and a 4" exhaust and my noise was 96db at 4500 rpm. And it was even quieter on the track. Some ppl asked what i had done to make it quiet. All i said i had bought a Coast Fabrication muffler for my car. And that made so much diffrence.
Try out a coast fabrication muffler in the middle and you should get the exhaust so much more quiet. you can even put one in the back for it to be even more quiet.
But they do burn up rather fast. Wich is why they are rebuildable. Well fast depends on the use. But i think they will last max 10 track days at the time.
Interesting
What packing material were you using (lightweight or other)?
I think it might burn up too quickly for most of the cars listed on here. They are all dual duty street/track day cars, not dedicated race cars.
Cool find. I know we have a problem with cheap glass packs wearing out within one weekend of racing. A rebuildable muffler with a turndown would certainly quiet things down a bit.
would an FD with DP and resonated MP stay under the limit with a stock catback? If I ever go to Laguna thats probably what I will do, just swap out catback with the stock one.
Im not sure what kind of packing they use. But they just changed out to something that lasts alot longer.
The thing you could do is make a second system with one coastfab muffler at the end that you only use for track days. I do know they are quite cheap to rebuild.
I used the most expensive one they had. As that turnd down the DB the most.
would an FD with DP and resonated MP stay under the limit with a stock catback? If I ever go to Laguna thats probably what I will do, just swap out catback with the stock one.
So the NASA west champs will be running a 105 DB limit. Ive never run a track with a sound limit so not sure where the car will end up. We have a single exit on the drivers side of the car with a dual into single muffler in the stock location on that side. The packing has been melted and blown out of the mufler so I'm planning to cut a hole in it and repack with some stainless steel wool then put a downturn in it to aim down and to the drivers side of the car...not sure if this will be enough for the non-turbo car....
We can't have silly pipes sticking out past the bumper. They would inevitably get munched in a potential contact situation...bump drafting is rare in PT but it does happen. Although we are usually doing the pushing...
Any experience with a 105dB limit day there and an ITS prep type non-turbo car?
If at all possible aim the exhaust to the left instead of straight down. I swear it makes a difference. Either way, I think you'll be OK with 105 unless your exhaust is completely uncorked.
We just had an unlimited sound day at LS two weekend ago! Most of the cars on the track were racers who were testing/tuning..lol, my ears are still ringing. The FD was about the least offensive car around. For once.
Try to run straight out the left side, behind the tire but ahead of the rear bumper.
Pointed at ground: echo=loud
Behind bumper: fills wake with waves,=loud
pro tip: use some kind of bendable tip on the muffler. If you are popped for sound, they will take away your quallie times unless you make a "bona fide change" to the exhaust. If this happens in last q, and you cannot make a change right then and there in the hot pits, then you have lost all your times for that session. Having something to bend/move/distort counts as "a change" and you can get back out for one more lap to throw down a flyer.
Laguna Seca was built near an Army base (Ft Ord). The base closed about a decade ago (maybe 15 years) and as time goes on, more and more people are building houses near the track. It's a nice area, so they're big houses with rich people.
It's pretty lame...All the new home owners complain about the noise, so unless its a big event like this weekend's superbike champs, they usually have a DB limit. 105 is actually pretty damn good, as they're usually like 97 or even less.
I'd run two mufflers just in case. One somewhere under the middle of the car and another in the rear stock location with an adjustable turn down pointed to the driver side of the car. You don't want to get DQ'ed once you are there. They will NOT let you slide.
I've spent my fair share of time seeing the meatball flag at Laguna. My single turbo FD with a borla muffler blows around 100-102 db at SCCA events (103db limit). But my 12A bridge is loud and needs lots o mufflers. I got flagged for sound at 2 or 3 events last year with my 12A bridge while I tried different combinations of turn downs, extra tubing pointing our the driver side of the car and adding a second muffler. I got zapped every time.
Second muffler attempt...even ran a piece of tubing another 18 inches to the drivers side resulting in a trip to the sound dude for a scolding.
I was preparing for the 2014 runoffs and finally decided to add two mufflers to my rock muffler and came up with this.
Yeah, it looks like a tuba and is heavy, but I got to run. The 2013 SCCA runoff champ in GT3 (came from Illinois with a fuel injected 13B) ran two laps in the 2014 runoffs before he got zapped for sound. He was using a rock muffler and was routing the exhaust in front of the driver side rear tire.
I see that Rock is hauling a long way to Laguna. Don't come this far without a plan, I guarantee it will suck.
I think i might bite the bullet and go with the full racing beat road race setup. I know it makes the power I need and will meet sound. It wont stick out from the bumper either... The presilencer hangs pretty low though so going of track is almost guaranteed to destroy it. It's an expensive option, but It's the only sure thing.
A midpipe with a muffler will make a difference too. Magnaflow makes a pretty nice one for the FD. I'm not sure about the FC but I'm sure you could have something fabbed.
Define your NA setup? I am hoping to get into tracking BIR within the next year and I feel my setup is not loud at all NA. I can only imagine with porting etc....
For those of you that are adding additional mufflers/restriction, just make sure you are keeping an eye on your EGT/af ratio as it will definitely need to be adjusted! I have seen people find this the hard way!
11-02-09, 03:55 PM
