I have a bit of a super loud dump-valve on my car (it was on the car when I bought it... but think it is an HKS SSQV, or similar) and it dumps just fine. However, whilst it is dumping, if I get my foot back on the gas I can hear it sucking air back in just as loudly. It's much louder and longer in the higher gears - eg. On the motorway.

Much as this sounds great and I can get the car to whistle all the way down the road... is it right? And should it be happenning??

There is an adjuster nut on the back of the unit - can anyone tell me what that is for?

 

Anyone...??

 

BTTT

 

I think you need to adjust the nut on the back to make the dump valve spring stiffer. It sounds like it is dumping under too light a pressure.. Either that or its fooked...

 

Cheers - which way do I adjust it to make the spring stiffer? I presume I wind it in clockwise - is this correct?

 

BTTT

 

Could it not be an airleak somewhere within the pipework??

 

Could be..

gsw73 - Did you get it sorted?