Manual boost controller vs poor actuator spring

Hi all,

I have just installed a turbosmart mbc on my stock 4efte, and opened up the valve a quite a bit...After testing i do notice a change in the turbo spool up response, the turbo sound gets louder, the dumpvalve gets louder, and the power throughout the rpms are just crazy, especially uphill...but when i check the boost guage, it remains on the same 13psi of boost, as before...i have also noticed that i can go up to almost 8000rpm, and the engine doesn't over rev...

i'm amazed by the outcome of the upgrade, but yet i'm confused, because the readings i get doesn't match...

So what could be the issue there?

what boost gauge do you have? ive had a lot of mixed results from boost gauges that did not give me an accurate reading

it says DEPO something on there, (it's a 2nd hand guage BTW), but it does remain fixed at 13psi at full boost...it just won't go above 13psi even though i raised the boost...Should i try a different guage?

and for a stock CT9 turbo, it sounds as if i have an external wastegate on...loud as f*ck...wsssssshhhhhhh!!!! at low rpm...

try a different gauge for definite.

getting a new one soon...but meanwhile i'll just raise the boost a little higher, to see if i notice any change in the power output, or any fuel-cut issues, due to the fact that i'm still using the stock ECU...

But apart from all that, the car is a beast, for a super stock setup...scared the shit out of me, on my first run uphill, but it's all good now, i'm very satisfied in the change of power...

If i'm not mistaken 13psi is almost 0.9bar right? and the stock 4efte ECU can handle up to 0.85bar of boost without the use of a FCD...so, how come my engine isn't getting any fuel cut/ boost cut?...is that normal?

Over the years I've found fuelcut isn't precisely the same on every vehicle. Quite a few factors come into play. Mk1 GT's seem to have a lax grip on that .85 you quote whereas I've seen 99 V's cut at .70 so it could just be ECU related. If you can cross reference with another gauge to check the reading it might answer it.