i have the turbosmart 38mm wastegate on my STS kit. Im running 10lbs, no BOV.

The other night I did a 30 WOT punch, and a 60 WOT punch. My dilemma is back when I ran 5lbs I could hear the compressor surge and it was pretty distinct. There usually was about 5"notes" in the surge when I let off the gas. Well When I upped to 10lbs a week or two back I still had the compressor surge. But when I did the 30/60 WOT punches last night there was basically no compressor surge. All I heard was a woosh of air. Any input on what my wastegate is doing? I do realize now that I need a BOV pretty bad to relieve the stress on the turbine, but I can tell that the wastegate is not working properly because im only spiking at 7lbs instead of 10..

Ideas...?

 

So has it ever gone to 10# or just spikin to 7#? And how are you controlling the wastegate? With a elec/manual controller or using a 10# spring in the wastegate?

 

It has been going ten for about 4-5 weeks pretty strong. It usually stayed at 9, hit 10 every now and then. But it was always consistent.

Its a straight up 10lb spring. btw A/F is good and no KR.

 

Just an Update:

took the waste gate off, took it apart, inspected it. Was able to blow the valve up and down with the spring out with my mouth, so it doesnt seem to be sticking.

Went over all the cold side piping and everything is tight.

Any other suggestions?

 

to me it kinda sounds as if your gasket is bad in the WG and maybe bleeding off or maybe a hole in a line somewhere maybe a boost leak. are you runing a manual boost controler? I know you already know but a BOV is very important you are stopping the turbine wheels evertime your under boost and close the throttle. the only reason im telling you this is cause when i first had the turbo on i didnt have a BOV and i smoked a 1300 turbo by bending the turbine wheel.

 

the metal flange gasket that goes from the exhaust to the WG? or is there another one internally?

yeah BOV is at the top of the list to get next..

when I was doing some 3-4psi runs a little bit ago I heard no compressor surge what so ever. It did sound like the air was wooshing out somewhere up front under the engine though. I still do have the PVC system and no there is no blow by anywhere..

 

well i have a tial WG and i have alittle copper gasket in side mine. so i figure yours would too. if your loosing boost it means there is a hole or a crack in something. unless you boost controller isnt working properley. even if you did have blow and your WG was set for 10 psi the motor would still read 10psi if thats what its set to. is blow by wouldnt even cause it.

 

I dont have boost controller. Just the turbosmart 10lb spring. For like 3-4 weeks i was spiking normally at 9-10lbs. The last week ive only been getting to exactly 7 everytime at WOT

It doesnt look like that copper gasket is leaking. Wouldnt there be black/soot around part of the flange if it was?

 

you shouldnt be able to blow thru it with your mouth ducky...that 10# spring is supposed to be pretty strong...

 

You would think there would be black around the flang. it just doesnt make sense why you are loosing boost then. are you sure it has something to do with the WG? Im not saying its not. but there is alot of other ways it could be looseing boost.