exhaust silencers Options

[lagos]

just wondering if any of you guys are using a universal silencer on a 3in tip muffler and what you would recommend?

im not looking to make my exhaust quieter, but i am looking to restrict the air flow a bit. i noticed that with my ebc totally off, my boost creep is crazy. it starts to hit 7psi and it stays there under 4k, but from 4-7k it starts to boost creep to 14psi. thats a lot of creep! im thinking that maybe i can create some backpressure with a silencer so that the WG has less exhaust flow to deal with. i figure the silencer is cheap enough to give it a shot. im also going to test my WG to make sure its not hitting the 3in DP i have.

so, post some silencer links guys and tell me what you use!

[jgreening]

There isn't just one solution. It depends on what the problem is.

Perhaps the wastegate actuator rod is bent
Perhaps the flapper door is not opening for some reason
Perhaps there is a leak in the pressure line going from the manifold to the boost controller
Perhaps the boost controller is faulty (a problem I had)

I am sure there are other potential causes that I am not thinking of.

[Insanity-74]

There isn't just one solution. It depends on what the problem is.

Perhaps the wastegate actuator rod is bent
Perhaps the flapper door is not opening for some reason
Perhaps there is a leak in the pressure line going from the manifold to the boost controller
Perhaps the boost controller is faulty (a problem I had)

I am sure there are other potential causes that I am not thinking of.

Thats much better 11/10...things you can check and look into and investigate and all very valid possibilities, but after working on cars now for over 15 years I can most definately assure you that an overly large exhaust diameter can cause boost creep if you have an inadequate waste gate....remember the CT series of turbo was only ever designed to cope with the standard internals producing the pressure, and with 0.9 bar...its all about exhaust gas velocity and back preasures....there is alot of physics type stuff invloved which I dont fully understand but it does happen.

A bent actuator rod is possible..unlikely due its location being out of the way, but if your not carefull when putting the turbo back on etc.

The flapper (wastegate) not opening fully is a real problem and admittedly one the most likely causes of boost creep...especially if you have one of the XS power type of down pipes which has is under designed and dosnt always allow for the full opening of the wastegate.

Manifold to Boost controller pressure leak..........highly possible in an after market boost controller set up...more likely to be a leak between the turbo itself and the solenoid for the actuator.

Faulty boost controller....the only way to find this out that I know for that is to bypass the boost controller totally and run the boost pressure dierectly off the actuators pre set pressure, which should be around 0.5 bar.

I have noticed this alot in American forums that everyone seems to jump straight on the 3" exhasust band wagon (no offence to anyone)...but unless you want to produce 400+BHP it really isnt needed, but I`m sure that noone will listen to my advice...after all I`m from England...what the F@@k do I know.

[jgreening]

I have noticed this alot in American forums that everyone seems to jump straight on the 3" exhasust band wagon (no offence to anyone)...but unless you want to produce 400+BHP it really isnt needed.

I think you raise a good point here. But there is dyno testing to prove that a 3" exhaust will result in modest performance gains at levels under that. Also, some folks initially build BPU 3sgte's with the intent of possibility upgrading later on. If thats the case, you don't want to pay for two exhausts.

BTW, I consider this a polite difference of opinion and apologize if my comments offended you. I am curious as to your opinion why some people experience absolutely no creep issues with a ct-26 (or ct20b) and a full 3" exhaust.