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Open intake + Bonez cat + PFS exhaust =

Old 05-31-08, 09:24 PM
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Open intake + Bonez cat + PFS exhaust =

100db
That's right. I got black flagged twice today at Laguna Seca for sound. I even have an extra resonator welded onto the PFS exhaust.

Legal for Laguna Seca is 92db. I consistently barked 99db. I stuffed some some steel wool into and clamped an elbow onto my exhaust tip, and was able to sneak by (until my elbow melted from the heat), but still...99's pretty loud.

...and getting meat-balled sucks.
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Old 05-31-08, 10:01 PM
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There is a 92db sound level at Laguna Seca? That seems ridiculous to me...
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Old 05-31-08, 11:09 PM
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Your lucky you got 92db. Most of the time it is 90db. I usually don't even bother running laguna with my rx-7, unless the price is right.
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Old 06-01-08, 02:13 AM
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The fog didn't help either. The whole area was like a fricken recording studio.

Fun day, though. The temp was just right and the track wasn't too crowded at all.



I think a muffler shop could make a stainless elbow that can be fastened onto the exhaust tip and stuffed with steel wool or something. The rain gutter model melted before I got to turn 4!
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Old 06-01-08, 11:02 AM
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I thought after the second time you were sent home? At least that is what they told us at the NASA event last year. I got it once for 97 and had to lift past the sound booth the remainder of the day. Same set up as you but a RB twin tip. Next time get a 90 and face it away from the soundbooth. I've seen some goofy exhausts buit to get around the noise restrictions.
What a great track though!
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Old 06-01-08, 11:16 AM
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Haha, did someone mention goofy exhaust set ups?


My custom dryer-vent elbow was molten metal by the 2nd lap.

You actually (at least with Trackmasters and Speed ventures) get three strikes when it comes to sound. With my steel wool stuffed elbow I was passing the requirement, but like I said, it melted and I got barred.
Maybe a muffler shop would make an SS one that will last...
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Old 06-01-08, 07:04 PM
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I run a 90 degree mandrel bent elbow to pass sound at Sears Point. I love laguna but sound is too much of a pain.
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Old 06-01-08, 07:27 PM
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Hey! that's a 7's Only car, huh? You must be having a f-ing blast in that thing. If it is from 7's Only, do you race it in their series? ( I had some "issues" with my FD at Buttonwillow, and they took care of me. While I was there, I drooled over the race cars.)

Yeah, the old elbow/stainless steel wool trick seems to be par for the course at Laguna. It's kinda weak that Mazda owns the track, but RX-7 owners can't really run there.
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Old 06-01-08, 11:51 PM
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Yeah, it's from 7s Only. I picked it up at the beginning of this year so I'm new to the series. I can't imagine anything more fun than racing these things around the track.

We run a 3" pipe into 2 magnaflows and the racket they make is ridiculous. The elbow helps pass sound but it also reflects it back into the car. My ears rang for a week and a half after the last sears point race, even with ear plugs. Can't complain though, gives me a legitimate excuse for not listening to the wife.
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Old 06-03-08, 10:12 AM
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There's nothing quite like the sound of an uncorked rotary.

I'm running into the same problem w/ my NA FC (RB head+mid, Corksport single exhaust). I'm having to run the silencer insert in the muffler, which is killing power. I have a turndown which I need to install, and I'll probably "open up" the silencer a bit with some well placed holes.

Yet another project <sigh>.

-b
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Old 06-03-08, 10:17 AM
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On an unrelated note (poor pun), how'd that FEED wing affect performance?
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Old 06-03-08, 10:33 AM
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Y'kow, It may have done a little something. My car felt a little more...planted on the high-speed sweepers like the Rainey Curve. I'm no professional driver, so it may have been all in my mind, but my '93 really seemed to feel more tail-happy when I had no wing.

Like I said, It's probably just my imagination, but yes, I think it helped.
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