need help w/-110dB Road Race exhaust system 13B n/a bridgeport
#1
need help w/-110dB Road Race exhaust system 13B n/a bridgeport
need help w/-110dB Road Race exhaust system 13B n/a bridgeport
--------------------------------------------------------------------------------
the problem is that I have to get my car down to 110 decibels.
my car now is 113.
my car is a FD brdigeport n/a
I dyno before doing the mod's @225whp and 147torq
I have the "long" exhaust system. RB road race header and I continue both primaries tubes independent til the diferential then the Y collector and megaphone then a Dynomax 3 1/2'' muffler.
since I have to drop bellow the 110dB I got 2 Dynomax bullet muffler and installled them on each of the independent primaries.
I installed them parallel (same length from the header flange)
didn't do any changes and dyno again @216whp and 141 torq
the torq curve became a wave up-down-up-down and huge power drop at high RPM's
I talked to a friend and he said that the bullet muffles had to installed at a different lenghts (not parallel).
any ideas on this?
--------------------------------------------------------------------------------
the problem is that I have to get my car down to 110 decibels.
my car now is 113.
my car is a FD brdigeport n/a
I dyno before doing the mod's @225whp and 147torq
I have the "long" exhaust system. RB road race header and I continue both primaries tubes independent til the diferential then the Y collector and megaphone then a Dynomax 3 1/2'' muffler.
since I have to drop bellow the 110dB I got 2 Dynomax bullet muffler and installled them on each of the independent primaries.
I installed them parallel (same length from the header flange)
didn't do any changes and dyno again @216whp and 141 torq
the torq curve became a wave up-down-up-down and huge power drop at high RPM's
I talked to a friend and he said that the bullet muffles had to installed at a different lenghts (not parallel).
any ideas on this?
#2
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have you tried an angled tip on the exhaust? how about some kind of airbox, lots of noise from the intake too....
i don't know about the presilencer thing, might as well try it
i don't know about the presilencer thing, might as well try it
#3
Rotary Freak
need help w/-110dB Road Race exhaust system 13B n/a bridgeport
--------------------------------------------------------------------------------
the problem is that I have to get my car down to 110 decibels.
my car now is 113.
my car is a FD brdigeport n/a
I dyno before doing the mod's @225whp and 147torq
I have the "long" exhaust system. RB road race header and I continue both primaries tubes independent til the diferential then the Y collector and megaphone then a Dynomax 3 1/2'' muffler.
since I have to drop bellow the 110dB I got 2 Dynomax bullet muffler and installled them on each of the independent primaries.
I installed them parallel (same length from the header flange)
didn't do any changes and dyno again @216whp and 141 torq
the torq curve became a wave up-down-up-down and huge power drop at high RPM's
I talked to a friend and he said that the bullet muffles had to installed at a different lenghts (not parallel).
any ideas on this?
--------------------------------------------------------------------------------
the problem is that I have to get my car down to 110 decibels.
my car now is 113.
my car is a FD brdigeport n/a
I dyno before doing the mod's @225whp and 147torq
I have the "long" exhaust system. RB road race header and I continue both primaries tubes independent til the diferential then the Y collector and megaphone then a Dynomax 3 1/2'' muffler.
since I have to drop bellow the 110dB I got 2 Dynomax bullet muffler and installled them on each of the independent primaries.
I installed them parallel (same length from the header flange)
didn't do any changes and dyno again @216whp and 141 torq
the torq curve became a wave up-down-up-down and huge power drop at high RPM's
I talked to a friend and he said that the bullet muffles had to installed at a different lenghts (not parallel).
any ideas on this?
Another thing I found was that the gauge of exhaust pipe makes a strong difference in sound levels. The thicker the gauge of metal reduced the tinnyness and keeps the car a lot quieter. I would also look at the intake side, as mentioned before. My car was very quiet, but after I added the 4 ITB's, all you can hear is intake noise as the car comes towards you. I need to create a muffled airbox now.
Eric
#5
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at laguna seca the sound guy is between turn 6 and 7, and it depends on the day, they are usually around 92db
if your test is different, then the DB numbers are going to be way different
#6
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Find out where they measure the sound level at your track (left or right side of the track) then add a 90 degree pipe at the back of your car aiming the exhaust away from the db meter. If you're at the track and are still having issues shift up a gear and/or lift a little when you're passing the db meter.
In the end, everybody has to meet sound so everybody takes a hit in the power when adding mufflers... so welcome to racing.
In the end, everybody has to meet sound so everybody takes a hit in the power when adding mufflers... so welcome to racing.
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