B pipe knocking

[Do_]

My mate has a sportex centre section on his car 2.25inch and it seems to knock once its hot. Any reason for this? Where could it be knocking and how do you stop it.

Cheers

 

[CTR_Paul]

I had a problem when I ran an OEM manifold and Toda catback, the problem was OEM manifold didn't drop down as far as the JDM Manifold or a race header. I swapped to a Toda mani and problem solved.

 

[Do_]

Ah ok then cool thanks mate

 

[milly]

I had this problem too, very annoying, what i did was change the small exhaust bung for a slightly bigger one by the cat, only about 5mm bigger but helped alot. i bought this from halfords for about (£3) - its the same hanger as the rear one on the backbox. But for a perminant fix you could heat up and bend the two steel hangers on the backbox to give more clearance.
Hope this helps.

 

[Marshall-P]

Could be the hanger on the B-Pipe is worn and perished producing a lot of movement on that section.

 

[Composite Guru]

Also something to take in to concideration is fitting.

The B Pipe is able to rotate slightly when being fitted as the bolt holes are not perfect to the bolt diameter and this can cause banging too.

It needs to be fitted with all bolts loosened off and the rubber mounts installed, then ensure a wooden wedge is inserted into any areas where it sits close to the chassis before tightening. Tighten as per normal.

 

[Do_]

Ok thanks people :-D seems to be ok at min but if it does start i will keep these in mind