garrett376

Hey Guys... planning ahead here... I am interested in those who have run Laguna Seca with a 964, what was needed to pass sound on the quiet days (92db I believe). What engine setup did you have: exhaust, intake?

Anyone have an MAF on their intake and pass the sound test? I'm thinking the barn door will need to go back on, along with the cat and secondary! But I'd like to hear from those who have run there recently.

Thanks!

race911

Funny you should post this with the thread over on the 993 board and what looked like a private Canepa rental with what appeared to be NO sound limits. (The poster heard cars, and went over to see what was up. Don't know how far away he lived, but I doubt it was in the Nicklaus course McMansion development adjacent.)

So, back to your question, as it's what I put up on that thread: I've never busted on sound with my 100% stock RSA #2. I had been warned a couple of times with my 100% stock, less secondary muffler, RSA #1. Now I just avoid the place, because it's not that interesting and the cars are up at Thunderhill anyway.

Tom W

Stock intake and either of two exhaust systems have passed for me...
(1) Stock headers, cat bypass, stock primary & secondary bypass was a consistent 89 db
(2) straight/equal length headers and an early 911 "banana" muffler passed

(3) Stock headers with cat bypass with a fabspeed dual outlet failed (96 db)
(4) Stock headers with cat bypass, fabspeed single outlet and a supertrap failed

Just remember it also depends on weather conditions. I believe that overcast days are more of a problem.

kgorman

Garrett,

I run there with both mufflers + cat bypass + no undertray + drilled airbox.

If I remove the secondary, then I don't pass just barely at 92db. I normally run with the secondary bypass, but I keep it in the trailer for Laguna.

You *might* be able to get away with catbypass, secondary bypass, and primary muffler if you use an undertray and a non-drilled airbox.

Tom W

Kenny - just points out the same configuration can pass or fail. FWIW, when I passed I had no under tray and an air box with no cover.

garrett376

Great info guys!!! Any of your have a spare secondary muffler support bracket, bolts and spacers??! I'll need to find one of those it sounds like.

race911

Uh......yeah. And I even can see the whole muffler now since I moved about 15 vending machines out of the way last weekend in my CAR shop part of things.......

FamilyCar

Cup style intake (fabspeed), B&B header, no cat, primary no secondary (LOUD)

...then I bolt a simple (and removable) fabricated extension onto the end of the exhaust which attaches to the tailpipe which points exhaust gases downwards. It sort of an elbow joint.

PASS, no problem on 4/7/08

I see a lot of ppl do the same style extension.

Note: LS now has wandering rangers that set up the sound station anywhere. Guys have been caught by them. Can't just lift at 5 and sometimes 7

race911

Was funny during the early years of turndown mania that guys were still getting popped. Oh, intake noise from running carbs. Duh.

StanAE86

I have 993 manifolds with sport cats and sport mufflers. The sport mufflers and cats don't do squat, it's just as loud now as when I was running the stock 993 cats and muffler bypass. I had tried installing the sport cats to fit some sport mufflers, just for Laguna. That failed to make the car quieter, so I had an extension made for the tailpipes that point to driver's left. In the tips of the pipes are a cross hair (you can barely make them out in the first picture) and I stuff the pipes with coarse steelwool as necessary, to quiet the exhuast. It passed at Laguna, but it's pretty elaborate. The guy I was in the pits with, just had 90 degree turns that bolted to his tips, and pointed to driver's left, but he was ready with steel wool too. He ended up putting in some when he got dinged in the morning session.

If you're nailed, they let you come in to try to fix it. Then go back out for a sound check without getting dinged. If you're dinged 3x, then your day is done. But you can do sound checks as necessary until you've found a way to pass.

I ran there on February 29th this year and didn't encounter any roaming sound guys, they were set up on 5 in the sound tower as usual.

Something cool that someone in the pits had was a db testing device they got at Radio Shack. Nifty. He just stood some distance away and measured as we rev'd in the pits. Under load, I think the car is louder, but if you got one, you could experiment a little in a parking lot at home (notice I didn't say in your neighborhood? heh heh), before you hit the track. Then you could be even more prepared.

Good luck.