bogging

[jaevans]

95 silvia, s14 sr20det with about 100,00km on the motor
stock boost high rpm (over 4500) full boos the car will buck, or loose power, or just start to fall on its face. my research has brought me to needing a mass air flow, new fuel pump, or intercooler piping.
it had an oil change 2000km ago, all other fluids flushed about 8,000 ago with new plugs and fuel filter. what do you guys think?
any impute would be much appreciated!
thanks Zilvia

[Mikester]

Did you verify the correct gap on the plugs?

Also, if you used octane booster- it will cause exactly what you are describing and the plugs are toast.

Another thing it sounds like is compressor surge, but I'm not sure this applies as you have verified stock boost(?)

[jaevans]

I did properly gap the plugs. I never use octane booster. I only use chevron 94. That's the highest I can get where I live. I thought compressor surge happens between shifts when your bov isn't working properly. How would it happen between shifts? I double checked boost with two different boost gauges. Both said 6psi.

[Mikester]

I did properly gap the plugs. I never use octane booster. I only use chevron 94. That's the highest I can get where I live. I thought compressor surge happens between shifts when your bov isn't working properly. How would it happen between shifts? I double checked boost with two different boost gauges. Both said 6psi.

Two gauges reading 6psi is definitely verification ;)

Maybe my terminology is off? I meant the flutter you get when the boost is set too high, and the turbine is basically 'choking' on air that cant pass efficiently through the motor under accel.

[jaevans]

Stock turbo should handle stoc boost right? Maybe she's on her way out. Il look into that. This afternoon I'm doing a smoke test and a pressure test on the intake. My money is on a boost leak. Will post results this afternoon.

[Mikester]

At this point, mine is too. Leaking at 6psi shouldn't be very hard to spot.