hi.
ive got a rb320and love it.
i put a dump valve on it and jap style hayward and scott exhaust and its sounds great. but when going along, since i put the dump valve on it sumtimes stalls or the reves get low and from as far as i can see there are no air leaks. i took it off the other day and the car runs fine. but when i did take it off the exhaust didnt pop and bang like it did before. is the dump valve causein the car not to run properly and is it doing damage ?????

 

in a word yes....dump valves can cause issues such as irratic idle, flat spots,fueling issues...if i were you ide go back to the standard dv.

is it just a backbox you have fitted?

 

I really wanted to get the HKS dump valve. Love the sound etc.

I then read an article about how it can actually effect the performance, unless you remap or something. The article said that the ecu doesn't know that it has an after market dump valve and compensates for it.

I will try and find the article for you as it will explain more details

 

Eight years on mine's fine - Forge VTA....

dunx

 

dump valve needs a stronger spring

 

yes it is just a back box and also the rear silencer i hav taken out

thanks for the advise