Exhaust back box???

[Ruffneck]

Hi, all my mates tell me that putting just a back box on, can reduce the performance of the car. After I put my Peco back box on, I have to agree! Anyone else experience this? I'm looking to buy a cat back system now for my MK1......

 

[edde]

Nope so long as it not a stupid size it won't loose performance.
Get rid of the cat as thats cna make a difference Lunner on here sell them £40 i think.

 

[steven.m]

How does it reduce performance? I vaguely remember someone telling me that bigger tailpipes suck air in??