OK guys.. I haven't personally measured the noise from the car but maybe someone could help me out..

I live in northern California a hop skip and a jump away from Laguna and Sacramento Raceway.

I run greddy twins w/ SGP dumps and 3 inch downpipes. No cats here. I am running 6 and 8 psi. Does anyone know what the DB is in regards to being 50 ft away?

Apparently at Sacramento raceway on the Wednesday night races there is a 90db limit at 50 ft away.

And at Laguna depending on day can range from 90db and up.


So onto the question. Has anyone ever measured their cars at WOT under load from 50 ft away with open dumps? i am curious to see how loud it is.. Thanks

 

If noone comes back with an answer, I think Radio Shack sells meters that measure sound volume in dB's, and I don't think they are that expensive.

 

Also here is a quick example of what some people are doing to attempt to pass the 90db limit at laguna.

Also FYI a stock FD at 4500 puts out 88 Db's supposedly.. Am i going to be screwed.. Probobally =)

 

^ That looks ridiculous! Yikes!

Now cars have to be quiet at the race track too?!?!?! WTF?!?! California is getting WAY out of hand with stupid restrictions.

 

That looks weird as hell.

 

Bahahahaha

 

i bet that's the sound it makes..

 

measuring dBs dependens on the "weighted scale" that is being used. but 90 dB is pretty quiet.

 

that may give you an idea of how loud you can be .... otherwise make friends w/ a local audio shop, most of the better shops will have a meter, and may be able to help you out w/ a number.

 

its gonna be around 90-100dB i would think

 

All tracks have a DB limit.
Yes lots of people will try to find out where the mic/sensor is around the track and route their exhaust to face the oposite direction to help (that porsche is a bit rediculous lol).

I have no clue how loud it would be but its got to be in the 90-100DB range. Mine are loud, but I can't tell you what loud translates to in DB lol. I know in tunnels and next to walls its kinda rediculously loud........remember that is exhaust being routed almost directly out of the heads and bypassing the exhaust system.

I believe there are small DP mufflers out there if you need them.

Tom

 

i would think its closer to 100-110 db.
after a good romp on the fwy my ears start to ring. With windows open of course.
The only issue w/ where the meter is that sure i can coast at Laguna between turn 5-6 but on the Drag strip it would sort of be pointless to coast there...

I will definitely need to buy a DB meter and see what it says when i roar past it at WOT

 

I know this is not FI related but my car is 92dB 4750rpm static test @ 1m at a 45 degree angle from the exhaust tip. 90dB @ 50 ft you car is gonna need to be loud to set that off! I have seen TVR cerbras with 4inch exhausts that did 106dB static test not fail on an 88dB drive by. But again this is not the same sound as open dumps! haha.

If you do get a dB mete and do so WOT drive bys please post up the results.

 

You will be over 90 for sure. Every car that I have that does no have cats ...measures over 95. My G35 with APS exhaust and 3.5" down pipes is over 90....and I know for a fact that the Z's around here with Dumps are louder.... Hope I am wrong

 

I used the SPG wastegate relocation kit on my build, but we ran the dumps back into the downpipes, which really helps reduce the noise. Here is a picture:



I have a Greddy Evo TT exhaust and my car runs relatively quiet. It might actually meet the 90 dB limit at 50 ft.

I have an Audio Control One-Thid Octave Real Time Analyzer, which also measures SPL. I'll test my car after we get everything back together.

 

awesome ttg35fort, cant wait to hear how it is w/ the dump's plumbed back in.
and i will most likely pick up a db meter this weekend see how bad it is..

 

just run it.. If they kick you out then u know ur too loud, if not keep running.. Damn i feel bad for you cali guys..

 

Just turn up the boost!! LOL, just kidding. I have open dumps running 9lbs myself. I'll be plumbing back into the exhaust as well. I drive my car daily and it gets a little old.

 

issue w/ seca is...
you get 1 warning...
then after first warning you get fined by the city of Monterrey 1k dolla =)

 

Whats the point in relocating and still dumping into the exhaust? Does it help spool up? I thought the point of relocating was to dump to atmosphere?