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Ok i really hate this one noise that my magnaflow does when i let the gas go at high rpms it makes a weird high pitch noise. what is that?

please to elaborate.

high pitched whine? squeal? psssh?

Sure its coming from the magnaflow?

Exhaust leak.

My magnaflow on my CES system doesn't make any noises like that.

its like a high pitch sputter like prrrt but high pitch. something like that i will record it.

Flip_x wrote:its like a high pitch sputter like prrrt but high pitch. something like that i will record it.

Heat sheild rattling? Mines doesn't make noise?

its from the exhaust. i dont have a heatshield anymore. its right after i go past like 5k rpms and let the gas go it makes a noise.

you took off all your heatshields, from the headers back?

the only ones i left on were under the gas tank (when i was n/a)

MK

the noise comes from the exhuast. like its a deep tone then it sputters out like a high tone for like 2-3 rpms when i let off gas

Flip_x wrote:the noise comes from the exhuast. like its a deep tone then it sputters out like a high tone for like 2-3 rpms when i let off gas

Sounds like a worn muffler bearing. Pepboys stocks them.

WRXdan wrote:Sounds like a worn muffler bearing. Pepboys stocks them.

Replace the O-pipe while your at it. Yours is probably worn out.

BAC5.2 wrote:

WRXdan wrote:Sounds like a worn muffler bearing. Pepboys stocks them.

Replace the O-pipe while your at it. Yours is probably worn out.

Good point...that is a commonly skipped step. The last, most common skipped fix is replacing the sphincter valve right before the muffler inlet. The valve is never replaced like it should be.

Here is a pic of a muffler bearing. This muffler was trashed, but if you use the access door then you can replace it without damaging the muffler.

MK

hahahaha

I don't recommend the practice of replacing the muffler bearing on an old muffler. For the cost of the new OEM-style bearing plus the labor of packing it (not to mention the special exhaust-safe technetium grease you have to use to do the job right), you might as well get one of the new modern mufflers that use sealed ball bearings. They usually come with the bearing already installed. The end result is a setup that requires less frequent maintenance while also providing less friction.

Oh, and a neat tip -- if you do decide to replace the bearing, or if the new muffler you get doesn't already have the bearing installed, you can use turn signal fluid as an assembly lube to help slide the bearing in place without putting too much force on the muffler's pinion gear.

I heard from the grape vine that Perrin is developing a ceramic muffler bearing soon for our cars. Should prove a 10HP increase due to the reduction in back pressure! Sounds like a cool idea!

Today is a sad day to call myself a legacycentral bbs member.

MK

Ceramic muffler bearings? I'm skeptical. Back during the energy crisis a lot of manufacturers experimented with that kind of stuff. They worked okay when the cars were stock, but any power-increasing modifications at all proved deadly to the fragile material used in the bearings. Trust me, you don't want pieces of shattered muffler bearing flying around in there, getting trapped in the gears and flying out the tailpipe.

i find this very funny.

It may sound funny now, but you won't be laughing when you're stranded on the side of the road because you neglected to maintain your muffler's moving parts.

its straight through

Oh.

I don't know anything about how those things work mechanically. Do they even use bearings in the standard sense?

vrg3 wrote:Ceramic muffler bearings? I'm skeptical. Back during the energy crisis a lot of manufacturers experimented with that kind of stuff. They worked okay when the cars were stock, but any power-increasing modifications at all proved deadly to the fragile material used in the bearings. Trust me, you don't want pieces of shattered muffler bearing flying around in there, getting trapped in the gears and flying out the tailpipe.

You're forgetting that in the 70's the fuel was 20% corn husk oil. This oil would break down the ceramic material. Today's gas has mineral oil, which is less acidic then CHO.

Huh. I didn't know that. You learn something every day.