I see the link for the silencer photo goes to FlowMaster, a prime example of engineering fail.AZhitman wrote: The point is, this is a typical silencer:
Putting that in an exhaust system is simply a band-aid for poor design. You CAN have a free-flowing system that makes good power and sounds great. We've proven it.
It's not "turbulence".Matina210 wrote:this crackling sound... It really meant that there was turbulence in the pipe, but I liked the sound as long as it wasn’t too harsh.
That crackling / popping is caused by the lean condition brought on by deceleration. When you lift, the throttle plate closes off incoming air and your ECU returns to a leaner mixture. However, you're still moving, which keeps the engine spinning, at an rpm that normally would want more air (and fuel) than your closed throttle plate (and turned-almost-off injectors) can provide. The popping occurs when sufficient fuel builds up in the chamber to "fire" that cylinder on the exhaust stroke of the engine.
Easier to show on a carb'ed car. Not harmful, and I agree - sounds way cool. Has ZERO to do with "turbulence".
Wanna confirm? Next time you're driving, press the clutch in on decel - It won't pop / crackle like it does with the clutch disengaged.
...all well within the variability of a dyno. One pull means nothing.Matina210 wrote:...showed a gain of 2 hp, and 5 lb-ft.
Their mufflers make the exhaust turn at sharp angles, usually with zero radius. My HKS silencer didn't look quite like that, and if 2hp and 5 lb-ft are within the variability of a dyno, then you're saying the dyno didn't prove it was restricting my exhaust. Having seen my results, I was agreeing with you that it did.
Unfortunately, I can't confirm anything about the crackling noise. I will say your explanation is much more technical than the people who told me for years my car was "backfiring", when I knew darn well that it wasn't. My S14 that made the noise was totalled in 2008, and sold to a body shop in 2009. (May her new home be a good one.) My new exhaust on the S13 doesn't make that noise, but it's loud. I think I'll have to go down to a 2" pipe. I thought it would be quieter than the S14, but the S14 didn't have a header.
I remember reading many years ago that the Hotshot header and A'PEXi N1 Dual exhaust made an ungodly loud combination, but it makes sense that any header makes your system louder.
So, for those reading this thread and trying to decide on a pipe size: Keep in mind that the header makes a difference in the noise level.
With a pipe size that narrows down to 2.25", my exhaust is so loud it made my brother-in-law complain, and he likes loud cars. He said it was making him naseous, and I asked, "You mean it's not giving you a headache?" So he said, "That, too."
It's a shame because it sounds so menacing at idle, and I don't know if a 2" exhaust will have the same rumble. Well, the 2.0" exhaust can still have a 22" resonator...
I'm going to do these one shot: "Wiring Specialties" harness (which are beautifully made), dual core radiator with electric fans and shroud and a stainless steel 2.5" diameter/22" resonator/dual tip BRM exhaust! ;]
