Megaphones, 103dB?

[logician]

I have a set of megaphones that came with my 2.7L 911. Will megaphones pass 103dB sound limit? Sears Point and Thunderhill have 103dB limits. Are Megaphones louder or quieter than straight pipes?

-Juan

[jpachard]

This very much depends on the motor. I build exhaust systems and my system sounds quite different form one motor to the next, even if they are the "same" motor. 103db is pretty loud though...

[bpick84]

Megaphones are usually louder than straight pipes....remember the old cheerleader megaphones. I just ran a track with a 104db limit and megaphones were not working. Go to a dirt track shop and get 2 Schoenfield 8 inch header mufflers(#83030 $15.95 each) and make up 2 pipes with these and a turn out. Works well and will not hurt performance. Make sure toi direct the turn out away from the meter. http://www.schoenfeldheaders.com/mufflers.htm

[addictionMS]

Juan,

At Sears I got nailed at 107db with straight pipes, 3.0 motor.

Jim

[cstreit]

Juan,

When I was running megaphones I built a sheild that could be rotated on the end... Essentially it had about a 25 degree bend that could be turned away from the sound station. A hose clamp held it on to the pipes. Reduced db level by about 3-4 total...

[jacko241]

Chris, what do you run for mufflers now?

[cstreit]

I'm just running a straight pipe... slightly larger diameter than the headers...

Certainly not optimal but untill I can get the car on a dyno, I don't want to bother guessing at what's going to work best...

[logician]

Everyone,

Thanks for the info!

-Juan