Cutting back boxes off a 3.0 tdi

[.Jas.]

I just watched a series of videos on youtube where they cut the back boxes off a 3.0 tdi (replacing the back boxes with a straight through pipe) and gained 20 bhp and 30 torques. Also it sounded great afterwards. Is this a bad idea? Will it affect the back pressure in the engine, maybe set off the EML? Or is it a cheap easy way to get great sound and a bit more oomph.

Discuss.....

 

[Dani_B19]

Turbo engines don't need back pressure, no exhaust is the best exhaust with a turbo.

Regarding the EML light it won't affect it, your only cutting the back boxs out so well after the lambda sensors.

 

[.Jas.]

Ooh so sounds feasible then. Has anyone done this?
I guess it'll affect resale value cause there's no chance of putting the old boxes back on.

 

[RAF_S7]

So no chance of putting the old boxes back on.

If you still have the original OEM (one piece) system it should have cut points indicated where you would cut if you needed to replace the back boxes due to rust/MOTmfailure etc. If cut there, any decent exhaust shop should be able to weld them back on, or use bold on jointing sleeves to reattach.

The problem l had when removing them, is that they are big, heavy, dirty lumps of steel (x2) and long term storage was an issue.

 

[desertstorm]

If you want to keep the OE look and gain the power and noise benefits just cut them open and gut the innards.I have done this on my 3.0 TDI B8. You won't get any problems with fault codes . I doubt you will gain 20bhp but there will be gains in pick up and torque.

 

[.Jas.]

If you still have the original OEM (one piece) system it should have cut points indicated where you would cut if you needed to replace the back boxes due to rust/MOTmfailure etc. If cut there, any decent exhaust shop should be able to weld them back on, or use bold on jointing sleeves to reattach.

The problem l had when removing them, is that they are big, heavy, dirty lumps of steel (x2) and long term storage was an issue.

Cheers. What did you replace yours with?

 

[RAF_S7]

Cheers. What did you replace yours with?

Mine wasn't the 3.0TDi, it was the 4.0TT (but the principle is the same) I put on a pair of free flow rear boxes.

You could cut yours off and put on straight pipe with chrome tails of your choice. The point I was making is that you can put the original boxes back on, if you cut the originals off in the right place