Boost Not Holding and BOV Question?

[DrifterProdigy85]

Im having a problem holding boost. Ive got a manual boost controller set to 1 bar and it hits 1 bar and then boost drops as the rpm increases. Holds 1 bar untill aorund 5000rpm then gradually drops to .8 bar by 7000rpm. I know i dont have a boost leak so im thinking its the manual boost controller or its my T25 wastegate. What do you think?

Ive got a Greddy Type RS BOV and it doesnt open for blow off till around .4 bar. It makes the compressor wheel flutter at any pressure under that. Is this adjusted too tight?

[NisanS13turbo]

Im not an expert but I'm also learning as I go and about your problem It could be a bad turbo. Maybe the turbo is either boost too high from previous owner or its not properly taking care off. Again it could also be the wastegate. GOod luck

[bruinbear714]

You're pushing your poor little T25 turbo too much at 1 bar.

[ca18det_boy]

/\ agreed, its alot like McDonalds, you can do it...but its not a good idea...

[makav3li]

try it with a different turbo or rebuild it

[DrifterProdigy85]

i know 1 bar is alot for the T25 but i thought it would still hold the boost. The turbo is quite healthy. Blows a very tiny bit of oil but not enough to effect my oil level in my engine. Car doesnt smoke either. I never thought of the turbo being too weak to hold 1 bar even if its at the efficiency point. One time a vaccum line popped off my boost controller and the turbo hit 1.5 bar for just a second untill i let off the gas. I figure that the wastegate is what controls the boost. If the spring in the wastegate is weak then it wouldnt hold the boost. Also read that manual boost controllers are ****ty most of the time anyways so thats what i think could be the problem too.

Anyone have anything to say about my BOV question?

[Colton]

Your t25 will boost to one bar, but it will fall off at higher rpms, I had this problem last year and I was using a greddy profec b 2 boost controller. A high quality boost controller willn't fix your problem, it's the nature of your t25. Also, oil blowing through your turbo isn't good at any amount. Rebuild your turbo, upgrade your turbo, or be happy where your at. I hope this answers your questions.

[virus77]

its common for all types of small turbos to lose boost at higher rpm's. Thats all she can dish out so either live with it or its time to upgrade.

[DrifterProdigy85]

cool thanks. Im gonna upgrade the T25 once i get some cash.

One last question, how do you know when the BOV is adjusted right?