Exhaust Volume..

[juiced99ws6]

Thought yall may find this interesting. I bought a cheap decible meter that actually work fairly well from walmart. It was pretty close to the readings at work that we got from a professional meter a while back. Anyways I have measure 4 exhaust setups with it so far.

1999 Trans Am- LM2, Jet Hot LTs and ORY pipe- 125.1 db
2002 Forumla- SLP LTs, high flow catted Y pipe, LM1- 125.3 db
2005 Pontiac GTO- SLP LTs, Stock Cats, resonator delete and 2 bullet mufflers- 125.2 db
2000 Firehawk- Stock manifold, no cats, flowmaster cat back, mild cam- 120.2 db

hopefully I will get to do a few more types of setups for people can get an idea of the difference in volume on the different setups. The first three were very similar setups and obviously the hawk was a bit quiter. Another thing is the Hawks reading was consistant through its rpm range with the bullet mufler setups were quieter at an idle and just gradually got louder through the RPM range.

[BlackLT1Z28]

So, those readings were at high RPM's and the maximum readings?
How are away was the device from the exhaust pipes?

[juiced99ws6]

yeah they were all around the 5,000 rpm range but I think every car hit the max level around 4,000 or so and just held steady from there. I just stood a few feet behind the cars.

[BlackLT1Z28]

Interesting. Because if I remember correctly, the noise laws where I live is a max of 85 or 90 dB's or so from 20 feet away. Or something like that. Unless they've changed it. But, that's good stuff. 125dB's is considered really loud. I'm sure those numbers are illegal in most states.

[juiced99ws6]

Interesting. Because if I remember correctly, the noise laws where I live is a max of 85 or 90 dB's or so from 20 feet away. Or something like that. Unless they've changed it. But, that's good stuff. 125dB's is considered really loud. I'm sure those numbers are illegal in most states.

I dont know how much they would register from 20 feet away though. Imay do another little test on my car tomorrow for shits and giggles.

[BlackLT1Z28]

A measure of open headers would be a kicker too. That would be loud!

[juiced99ws6]

yeah.. I would also like to get some stock measurements too. only problem is I dont know anyone with a stocker right now!

[BlackLT1Z28]

Yeah, stock exhaust f-bodies are a rare find nowadays.

[9t8z28]

Test the decibels from the distance that is the standard for testing. I am sure is should be different. How close were you holding it to the pipe?

[jess]

I have and will inform the police, that they should be really doing their job by investing their time with those 100's and 1000's of harley riders who have terrible sounding bikes. Those bikes did not come that way from the factory, as most people know, but for some reason the State Police as well as the County don't seem to mind them. Now I don't want to see anybody get in trouble, but you might think the police would leave the fbody few alone.
Guess I'm on the soapbox now, but in 1972 I had a 1969 Z-28 with chambered factory pipes, and was given a ticket then. It would really crack like thunder when I would take it to 7000 rpms and back off it in 1st or 2nd gear. But man those harley bikes are that loud but they sound like , well you know what they sound like.

I think we can use our heads and still enjoy our loudmouths and other good breathing systems spoken of on this site.

Just my .02

jess ...........

[Chevythunder17]

Good data to have. Interested to see a test @ the 20 foot standard.

I got a ticket with my 2000 SS a couple years ago. Had a Loudmouth on it, and I was merging onto the highway from a short ramp. I didn't exceed the speed limit, but I went from 20 to 60 in a hurry. This upset the highway patrol officer that was coming up on my left side as I did this. I made him drop his doughnut so he pulled me over. He tried to get me for removing emissions devices (said I removed two of the cats). I told him that these cars have the cats up off the manifolds. Then he asked where the federal emissions sticker was. I pointed at the wheelwell where is always is. He was pissed...

[jmhvenom]

how much did that meter cost? I would love to test mine. I have my stock Z/28 exhaust on there still. I also have Pace LTs, ORYP, no cats, 2 cutouts on the y pipe.... would like to see the difference. I am pretty sure I am legal with the cutouts closed so I think I could get out of most tickets.