I think i already know the anwser is going to be no, but i will ask anyway.
Put a forge dump valve on my Rb5 (my99) sunday and its making all the right noises, my question to you is
"by putting a dump valve on a car, can this reduce the performance?"
All the joins seem to be sealed but there does not seem to be as much KICK in the car as before. Not done many miles since the fitment so not really tried it out properly.

thanks for any comments
Adam.

Cars spec:
Full scoobysport de-cat
Tec 2 ecu
K&N
Optimax

 

If it is a brand new dump valve & everything is fitted correctly and no leaks it should not drop preformance. They can alter the fueling slightly making it run a bit richer at times though.
Sure it is not just you being paranoid? Done that myself when I have fitted different bits.

 

I felt the same after fitting mines but I'm pretty sure its my imagination.

 

If its a recirc and setup / installed correctly then there should be no problems.
If its a VTA, then, well - can of worms time

 

You really should not have any problems .
If you are concerened plesae call Forge on 01452 380999

 

As people have said, it's all in the mind.
Seems to be ok now. maybe the ecu needed to reset due to it running richer.
All fine now, just deciding wether to keep it or not.

Thanks Adam