Headling 0 Posted September 21, 2007 hi guys, i am looking to get a dump valve for when I have my 2.0 8v put in, having a look on the bay, does it matter what type i go for? or is it a case of any dump valve will do? i know its a bit chav but it will be a laugh till it annoys me! Share this post Link to post Share on other sites
kyepan 291 Posted September 21, 2007 hi guys, i am looking to get a dump valve for when I have my 2.0 8v put in, having a look on the bay, does it matter what type i go for? or is it a case of any dump valve will do? i know its a bit chav but it will be a laugh till it annoys me! It may already have a dump valve plumbed in, probably a recirculating one, that puts the air back into the system, most cars do. unless you've severely hacked the inlet tract to get it to fit. I would go for a recirculating if it's not present, as it does not cause the mixture to richen and will be less leaky, which in turn may throw out the fuelling and air metering at idle and part throttle. Atmospheric ones dump the air out side the system, as the air has all ready been measured for when the fuel is squirted in, you'll get overfuelling on over run when its dumped, which may cause it to pop and bang. or if you have a cat ruin it pretty quick. how it sounds to you is up to personal taste. Share this post Link to post Share on other sites
sonofsam 5 Posted September 21, 2007 (edited) hi guys, i am looking to get a dump valve for when I have my 2.0 8v put in, having a look on the bay, does it matter what type i go for? or is it a case of any dump valve will do? i know its a bit chav but it will be a laugh till it annoys me! It wont be long! lol Good fun for a while though! Hi Mark, yes it does matter, you want a single piston dump valve, for cars without Air Flow Meters, as our engine use a MAP sensor instead. Atmospheric DV will make a whoosh recirculating will be pretty quiet as the air gets put back in the system ~ some 2.0 turbos had these fitted from factory, mine however did not. Would buy new if you can mate, check out forgemotorsport. Sam. Edited September 21, 2007 by sonofsam Share this post Link to post Share on other sites
van cleef 0 Posted September 21, 2007 SSVQ or a universal HKS are the ones i would probably go for. Share this post Link to post Share on other sites
rapidmi 4 Posted September 21, 2007 why a single piston? i use a twin piston and mines runs amazingly Share this post Link to post Share on other sites
Henry Yorke 269 3 Cars Posted September 21, 2007 I have a twin piston. It just seems to make a noise like a fut-tish! I think it is overkill, but it was a free brand new Forge one so it went on. You do need to run one of sorts otherwise you get "wastegate chatter" which is actually turbine stall not good fo rthe life of your turbo. Share this post Link to post Share on other sites
cybernck 402 1 Cars Posted September 21, 2007 with MAP-equipped turbo cars, you can run diaphragm type ones as well. Share this post Link to post Share on other sites
whizzer71 0 Posted September 28, 2007 More than advisable when running xtra boost too ! Share this post Link to post Share on other sites
Malachy 0 Posted September 29, 2007 (edited) Atmospheric ones dump the air out side the system, as the air has all ready been measured for when the fuel is squirted in, you'll get overfuelling on over run when its dumped, which may cause it to pop and bang. or if you have a cat ruin it pretty quick. how it sounds to you is up to personal taste. this does not matter on the 8v turbo, it uses MAP sensing not AFM, so measures pressure in the inlet manifold to sort fueling not volume of air passing an air flow meter after the air filter. therefore dumping air in a map based car before the throttle body has no effect on mixture at all. on an afm metered car it will as it will of been measured as you say and fuel setup for that.this means for afm metered cars you need to run twin piston types to help get over this problem, or run a recirc. on MAP based cars you can run anything. so basically you can use pretty much any dump valve you want, although i would choose higher quality as the cheaper ones can leak causing boost loss. regards Andy Edited September 29, 2007 by Malachy Share this post Link to post Share on other sites
bales 1 Posted October 1, 2007 Try without one first and see which noise you prefer..... Share this post Link to post Share on other sites
