Boost presure problem, will not hold, help

[turboex]

Ok i have a stock sr20det redtop and only mods realy are 3inch exhaust turbo back, and intercooler. Now when i boost 7psi the car holds 7 psi, but i tried 14psi and im having problems. The car will boost to 14psi say in third gear and then after a sec or two the boost drops and settles at about 9-10psi. I checked the piping for leaks (via presure tester) and its fine, i check the exhaust for leaks and nothing there. Now for my boost controller im using a 2 year old turboxs unit, would this be the problem or would it be that the stock wastegate actuator just cant hold that much. thanks for the help

[BuudWeizErr]

Stock wastegate actuator will hold more boost than the turbo will.

It's the boost controller.

[turboex]

The weird thing is that its a dual stage boost controler, and even if i set both stages at 14psi it still drops to 9psi. Its just weird that both halfs of the controler would be bad

[quiksilvia]

could it be the fuel not being able to keep up? maybe? just an idea, or the ecu and air going through.....i dont know

[turboex]

Its not the fuel system because the last turbo i had on the car held boost fine at 14psi, so it has to be the wastegate, must just be old and played out i guess

[MojoMan]

Could it be that its just a t25 and it sucks azz. Its your boost controller. Could be your wastegate. Certain boost control units dont help to hold boost properly. I had this same issue before I got the apex avcr. It helps to hold boost and decrease boost spikes. Seriously though it is just a t25 and it is notorious for boost drop off at certain rpms depending on how much air your pushing thru the motor and what vacuum it creates. If your car was tuned on a dyno you could proly get rid of it.

[Movingviolation240]

My money is on the T2 small being 'too small' and not flowing enough air to make any boost. Happens all the time with CA's and the crappy stock turbo's. Totally disconnect the wastegate from any boost source and see what happens when you roll into it at high RPM's in 4th gear. It will overboost at first, and then if it falls way off it's your motor outflowing the turbo.

You need a bigger turbo.

Paul

[quiksilvia]

might as well get a t88

[Unnatural]

might as well get a t88

Hey why stop there...get a Turbonetics Y2K. :ylsuper Did you check the wastegate? It's very possible that an older wastegate is leaking some boost.~Brendan

[Movingviolation240]

I can't see the wastegate being hte problem. You know you COULD have a plugged cat that's causing the thing to not want to perform correctly (too much backpressure to overcome so it dosn't make power like it should).

Is the thing lagging more than it used to? I'm still leaning towards my original assumption that the turbo is just to small to move that much air on a hot summer day.

Paul

[Unnatural]

Is the thing lagging more than it used to? I'm still leaning towards my original assumption that the turbo is just to small to move that much air on a hot summer day.

Paul

True...another likely problem.~Brendan

[turboex]

Yeah im thinking the same thing, ill try a new boost controler. I have no cat as of now, so its not that but yeah the turbo is small

[RobDET]

i had a 98 GSX Eclipse in 2000 and it wouldn't hold more than 10-12 with the wastegate actuator totally disconnected.

It's the T25. It just can't flow enough to keep the pressures up at high RPM. Also My old man just bought a GVR4 and the stock turbo that was on it was all caked on the exhaust side with carbon. the opening was literally the size of a quarter.

::EDIT:: it would spike up to 20 but then fall off FAST