Need a Muffler-save my Ears-X Pipe Installed with RMB!
08-11-2012, 05:42 PM
#31
Race Car
The best for a DD is a stock GT exhaust (rear and intermediates in place) with X-pipe and high-flow cats. The alternative is all stock except for an RMB, but no reason to do that when the X-pipe provides a substantial power increase.
Dan
'91 928GT S/C
475hp/460lb.ft
Dan
'91 928GT S/C
475hp/460lb.ft
08-11-2012, 10:40 PM
#33
Race Car
Thread Starter
So I put an 87 Resonator (rear) on-actually Pete, El Greco did.
So X-Pipe plus high-flow Cats plus smaller mid-size (91) silencers plus 87 Muffler sounds good.
Will take the larger mid size (87) and put those in with RMB for comparison.
Pete is going to rig the RMB to his 86.5 for giggles first.
So X-Pipe plus high-flow Cats plus smaller mid-size (91) silencers plus 87 Muffler sounds good.
Will take the larger mid size (87) and put those in with RMB for comparison.
Pete is going to rig the RMB to his 86.5 for giggles first.
08-12-2012, 03:04 PM
#34
Under the Lift
Lifetime Rennlist
Member
Lifetime Rennlist
Member
I currently have 87 rear section with RMB and stock cats. Slightly too quiet. RMB plus smaller resonators (88+) is perfect for my tastes. So, for me that covers the stock cat setup situation.
If you are running an X-pipe with or without aftermarket cats, just about anything except some custom setup has an resonance at 2200-2400 RPM that is just plain annoying. The sound at idle, take off and above 2400 RPM is fine and very healthy sounding. The funky, farty, ricer coffee can sounding resonance is the problem. With my 2.54 rear end and 4 speed auto, it's right in the highway cruising range. 87 rear section with larger resonators than later exhausts reduced it but it's still too prominent. Dumping the RMB for a stock rear muffler will quiet the exhaust down TOO MUCH. The stock rear muffler is very effective for those who want to use an X-pipe for power and prefer or don't mind silence.
If you are running an X-pipe with or without aftermarket cats, just about anything except some custom setup has an resonance at 2200-2400 RPM that is just plain annoying. The sound at idle, take off and above 2400 RPM is fine and very healthy sounding. The funky, farty, ricer coffee can sounding resonance is the problem. With my 2.54 rear end and 4 speed auto, it's right in the highway cruising range. 87 rear section with larger resonators than later exhausts reduced it but it's still too prominent. Dumping the RMB for a stock rear muffler will quiet the exhaust down TOO MUCH. The stock rear muffler is very effective for those who want to use an X-pipe for power and prefer or don't mind silence.
08-13-2012, 02:16 PM
#37
2200 RPM is about 150 Hz; 4500 RPM is 300 Hz. I had drone at 2200 cruising speed, measured at 300 Hz. Until I held it at 4500 RPM, I never noticed how much MORE drone I had at 4500. Turned out I had 300 Hz peak at all RPMs, but 2200 and 4500 engine speed exhaust sound was in sync and added to cause drone.
Speedtoys added a resonance tube to a single exhaust to correct his 150 Hz drone; I corrected my 300 Hz drone with a single exhaust without resonance tube (although added one later, which 'rounded' the exhaust note).
Speedtoys added a resonance tube to a single exhaust to correct his 150 Hz drone; I corrected my 300 Hz drone with a single exhaust without resonance tube (although added one later, which 'rounded' the exhaust note).
