I have a 2000 Civic SI thats turbod, Im running an OPEN dump tube vented to the atmopshere. Now it doesnt do this at idle but as soon as I step on the gas at ANY RPM it sounds like a lawn mower or Go-Kart. ( never should have done this) but yes I bought a wastegate off ebay, suppsed to be 7PSI spring but I was already at 10.5 PSI on the dyno. With that being said the WG is obviously bad, so with a better WG will the mower sound go away or should I just loop the dump tube into the exhaust? id like to keep in open if possible but cant stand the horriable sound. Thank you

 

Anybody have a similiar problem???

 

do you have the valve seat installed in the wastegate to the flange on the manifold?

without that, my car how sounded like a lawn mower..

http://www.youtube.com/watch?v=fna88K-3CJ4

 

Yes I do. I think the problem is that since my wastegate is supposed to be 7PSI but it was goin to 10.5PSI at 5K RPMs its just opening up right away and that the noise is coming from my dump tube. Im gonna get a tial 38mm .90 BAR and see if that fixes the problem, if not im goin to just have the dumptube loop back into the exhaust.

 

i see. alot of ebay waste gate tends to get stuck open..get the tial for the better and see if it also fix the problem. report back.

 

Just bc its boosting more than the spring is rated for doesnt mean its bad. Alot of things can cause overboost. Put your hand under the dumptube at idle and see if you can feel any warm air coming out. Does it make this sound when its below full boost or at full boost? It sounds like a regular old exhaust leak to me. Check the exhaust connections, manifold and turbo exhaust housing for evidence of soot.

 

Everything is relativley clean underneath as far as soot, no exhaust leaks can be found even took it to an exhaust shop. When its below full boost is when it sounds the worst, at full boost it goes away or its there but I just cant hear it.

 

i know my open dumps dont sound anything like a lawn mower. it just sounds like a lot of rushing air.... a really loud SHHHHHHHHHHH!!!!

 

Yeah my last two set ups with an open dumb sounded awsome, thats why im thinkin my problem is with the wastegate. Its a cheap one off ebay