decible levels
 

anyone know the decible level of stock hp 500s carb w/ twins
at idle.

also stock 1993 502 mags.

pa laws are 88 decibles.

thanks

Re: decible levels
 

a dB meter is about 60 bucks at Radio Shack.

I think that they use the A weighting for the test.

Re: decible levels
 

I just had my twin HP 500s (carb) tested at 91.3 dbl ... this was WITH HPI mufflers. I had hoped for a lower #, but I passed (had to be under 91.5).

Re: decible levels
 

I had a 1992 Scarab with 502 mags and it was 92db-got a ticket in WIS

Re: decible levels
 

Make sure the cops are do the test properly.. I know here in Mich they dont follow their own rules. One meter back and 1.5 meters high, if I remember correctly. Standing on my swim platform that is about chest height for me. They usually put it 1 foot from the end of the pipe. I just stay away and have big mufflers and shotguns.. they drag in the water and that helps.. Go to radio shack and get the meter, and check it yourself. Carry a tapemeasure and a copy of the law if you pass with your meter, theirs should agree. There also should be no abient noise in the area (jet ski's, etc) and no reflective surfaces.. like the side of their boat.. Some around here go to court and they win..
Dick

Re: decible levels
 

I'm in PA also and was wondering about that, I have 454mags....

Re: decible levels
 

Through hull exhaust above the water line, no mufflers and you will fail. The difference of 88 to 91 (3 dbs) is twice as loud. The guys with mufflers are running 91 and you need 88. A outboard fishing motor is about 88. Get the exhaust below the water line with mufflers if possible.

Re: decible levels
 

Good point. Or any kind of seawall.