Hi Guys,

After running my V4 RA with a cat back system for a long time, I have finally changed the standard front / dump pipe to a aftermarket system with the bellmouth collector.
The car goes much better now, the only strange change I have noticed is a tad more turbo noise and the BOV is very quiet compared to before when it would 'woosh'. Its a standard BOV, just wondering if anyone else has noticed this? when changing exhaust systems?

 

Make sure you get the map checked/ remapped for the exhaust. Standard recirc valve shouldn't really whoosh, maybe you had an exhaust leak?

 

If the exhaust is quiter you will notice things/differences. I found that when i swapped to my H&S from the Japspeed.

 

Aint that the truth, when I changed the chav box on my Type R to a revolution system, I remember driving along thinking 's**tttttt there is loads I have to do on this car'