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Posted by: trekkor Oct 25 2004, 08:35 PM

Is it dependant on venue? Alameda for example.

I want to run these mega-phone, trumpet, zoomie pipes I got from Martin Baker.

I know they will be LOUD. Will they boot me. ( make me muffler up )?

KT

Posted by: Jeroen Oct 25 2004, 08:48 PM

megaphones give no back pressure so you'll prolly end up with very little low rpm torque
not good for AX...

Posted by: trekkor Oct 25 2004, 08:52 PM

But, I might like the sound...

KT

Posted by: nebreitling Oct 25 2004, 09:13 PM

they'll be loud as shit. i should hope you'd be stopped from running, but GGR has seemed pretty relaxed about noise limits at the last few AX's. i think the limit at Alameda is 94db, but there were atleast 4 or 5 cars last AX well above that...


but i don't think they'll help you in an AX anyway

Posted by: nine14cats Oct 25 2004, 09:46 PM

Hi Trekkor,

The Alameda sound limit is supposed to be the same as Laguna Seca....92db. At Alameda I run my Laguna set up which makes the sound limit at the meter shack just after turn 5. All other Auto-x venues I was able to use my Phase 9's which would work out to ~98db on my 2.7 liter 6 with headers.

I think you will be too loud with the megaphones, although there were several cars this year that sounded too loud.

Bill P.

Posted by: trekkor Oct 25 2004, 09:55 PM

I might put 'em on Thurs night and buzz around the back roads scuffin' the Yok's. Playin' race cars

KT

Posted by: McMark Oct 25 2004, 10:07 PM

Come by here and see if I'm home. I wanna hear.

Posted by: Randal Oct 25 2004, 10:12 PM

QUOTE]i think the limit at Alameda is 94db[/QUOTE]

That is the limit, but it's not scientifically enforced. The way it works - if anyone complains about a car then the AX chairman let's that driver know there is a problem – and expects it corrected before the next event.

BTW if the sound level was measures/enforced uniformally amongst all runners, then there would be lots of people changing mufflers between events.

As to the next question, who are the biggest complainers, you’ll have to guess.

Posted by: trekkor Oct 25 2004, 10:19 PM

Mark, If I come by you'll hear me come across Silverado Trail.

Randal, I'm thinking, 911 guys?

So, if I show up all loud and obnoxious, do I pack the Bursch in case someone doesn't like the vroom, vroom?

Trek

Posted by: Randal Oct 25 2004, 10:24 PM

Nope, not the 911 guys.

Although my calculated guess is that most of the offenders do drive 911's.

Did I tell you Trekkor that I heard a 911 with 40 series flowmasters and that it sounded great, but not loud?

Posted by: trekkor Oct 25 2004, 10:29 PM

I like a loud race car.

So, maybe the people who bring their sleeping babies with them are grumpy.

Oh, BTW, Randal, I'll be down at HPH in the morning for the alignment and....I'll surprise you!

Trek

Posted by: Randal Oct 25 2004, 10:35 PM

Mr. T.

Give me a call in the morning and maybe I pop up for lunch.

Maybe Brad will be available as well?

Posted by: nine14cats Oct 25 2004, 10:50 PM

Randal and Trekkor,

What time for lunch?

Bill P.

Posted by: Britain Smith Oct 25 2004, 10:54 PM

I would be in for lunch also...let me know what time.

-Britain

Posted by: Demick Oct 25 2004, 11:02 PM

This weekend is at Candlestick. Noise shouldn't be a problem there. Alameda is where excessive noise is a problem.

There was a guy at the WCC with a nitrous 914. He had some straight pipes similar to the megaphones you want to put on. I was surprised that the car was not nearly as loud as I expected.

Demick

Posted by: Mueller Oct 25 2004, 11:05 PM

the sound you hear while [b]in the car/b] is loud obnoxious noise to people outside of the vehicle

I also see no reason to try and "test" the sound limits just 'cause you think your car will sound cool or that you "want" to get the car blackflagged for being loud....maybe it's just me, but i'd be embarrassed getting dinged for having an exhaust that i knew from jump street was just put on so that I get noticed while driving out there on the course...

I'm not trying to be ass, but I think this boarders on being inconsiderate to your fellow racers......

now if you are putting on an exhuast that you know will give you XXhp and you need that edge, that is different in my opinion...(off my soapbox )

Posted by: Britain Smith Oct 25 2004, 11:07 PM

It wasn't that loud to you but you weren't driving behind it and sniffing the fumes!!!

-Britain

Posted by: McMark Oct 25 2004, 11:12 PM

Okay, if it's going to be a big lunch gathering, maybe I can bum a ride with Trekkor and join in. What time's your appointment Kairos?

Posted by: trekkor Oct 25 2004, 11:17 PM

Mike, thanks.

maybe I should reconsider.

Good points.

I'm not a showboater, never have been.
I like the sound of loud motors, always have.

I love the sound of a stinger in a covered parking garage or tunnel.

I had a VW crew cab with a 2110cc and stinger, loved it.

KT

Posted by: Mueller Oct 25 2004, 11:28 PM

not to diss him, but when he left Laguna Seca, my wife and I watched him go up a small hill, as his car got louder and louder my wife asked why the car was getting louder, but not going any faster going up the hill???

the proportion of sound to speed was not very even

Trekkor, at least give them a try, maybe they wont be as bad as we are making them out to be

Posted by: Randal Oct 26 2004, 03:25 AM

Usually 11:45am is a good time to show up.



How would you feel if the reason for the loud exhaust was horsepower?

Posted by: Racer Chris Oct 26 2004, 07:01 AM

Those megaphones will hurt the power, maybe even worse than your Bursch.
You also run the risk of burning a piston if you don't re-tune the engine.
A single megaphone on a 4-1 header would be a much better idea.
If you want to hear them I suggest you put them on, rev up the engine in the driveway, and then throw them in the scrap pile.

Posted by: rhodyguy Oct 26 2004, 07:39 AM

the guy with megaphones and nitrous wasn't loud??? on the freeway you could hear him 1/2 mile ahead of you when he got on it. i don't think the juice was activated either. i wonder if the engine still runs?

kevin

Posted by: i love porsche Oct 26 2004, 07:52 AM

whats the deal with having to re-tune the engine for the megaphones?

would megaphones be good for trackdays? (im thinkin pocono) any suggestions racer chris?

Posted by: Racer Chris Oct 26 2004, 07:59 AM

If the engine is tuned for a muffler that has backpressure the megaphones will lean out the engine significantly.

Since the exhaust pulses on each side of the engine are only 90 degrees out of phase you get no help as far as scavenging goes with that style of tailpipe, so a 4-1 header is a much better choice. A megaphone setup on a 4-1, properly tuned, would work fine at the track.
In fact I have a used European racing header that came with a megaphone. The collector was shot though, so I plan to make a new collector and sell the system.

Posted by: trekkor Oct 26 2004, 07:35 PM

I put them on

Running up throught he gears on the backroad was amazng, though. Maybe I'll drag race tommorrow night at Sears.

Don't know if I even dare leave them on.

KT


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Posted by: McMark Oct 26 2004, 08:02 PM

I could hear you forever. I stood out there and listened to you shift.

Posted by: Series9 Oct 26 2004, 08:21 PM

I think loud is fun, especially for racing. Hell, even my 'street' mufflers are probably over the legal limit (what ever that is in NM).

I bet if you take it to the drags like that, no one will complain, but then they are drag racers...

Posted by: ! Oct 26 2004, 08:36 PM

Dude....proper tools fer proper fools......


Read the rules, bring a DbA meter and quieter muffs....trust me ...BTDT got the freaking tee shirt to prove it.....

Got my ass booted at San Diego one day....whipped out MY meter....showed that were all wet. They were using DbC rating that showed I was over the limit...bullshit....the rules said Db fucking AAAAAAAAAAAAAA

Didn't make a whole lotta friends but I made my point and I don't live down there.....made my runs and qualified for the HI AX championship for 1999.....

BTW....if ya wanna borrow my meter....just ask.

Posted by: trekkor Oct 26 2004, 11:08 PM

Why bother, Mikey, didn't you hear me from there?

KT kowabunga!

Posted by: ! Oct 26 2004, 11:09 PM

Woof!!!!

Posted by: trekkor Oct 26 2004, 11:17 PM

Good!

I feel sorry for all the people above me in the parking garage. I bet they thought the thing was coming down.

I had to baby it down 3rd street so the kids wouldn't cry

It's my evil twin.

KT

Posted by: trekkor Oct 27 2004, 09:26 PM

I'll video some drive-by's tommorow so I can judge the sound levels.

KT

Posted by: Brad Roberts Oct 27 2004, 09:41 PM

The reason they nailed Randal... he likes to fry the tires from the start so he revs it up... everyone else is out on a Sunday drive....

I have yet to see ANY PCA autoX where a sound meter was in use...



B

Posted by: trekkor Oct 28 2004, 08:53 PM

I've run the car for for two seperate sessions, rather...ahem, hard.

The inside of the trumpets are black ( running rich ).
I must have the fuel pressure set high already.

I'm leaving them on. I'll change out during break to compare the performance.

Only 4 runs of deafening chaos.

KT

Posted by: trekkor Oct 29 2004, 03:29 PM

Shot some video today. Not really that loud.
The cars at the vintage racing at Sears a few weeks back were louder.

KT

Posted by: d914 Oct 29 2004, 03:35 PM

Roebling rd allows 104db, I can't run megs. My buddy got pulled at 107db on a small six. Plus they mainly help towards red line.

Posted by: trekkor Oct 29 2004, 03:42 PM

zoomba


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Posted by: trekkor Oct 30 2004, 10:20 PM

I ran the megaphones all day with no complaints.
Some people actually enjoyed it

It added to the fun for me.

No noticable power loss or gain.

Good fun... Long course. 1:22 for me.

KT