Boost adjustment

[John S]

Hi all, some more advice needed. Even though my maestro turbo is well used mechanically (over 100,000 miles) I want to make sure it's safe to turn the boost up within the confines of the pop off valve limitation and still evade detonation i.e. 12.5 psi or so. Will a reprofiled carb needle really be necessary below 13/14 psi? I just want it to perform more like it did back in the day even though I don't use the performance all the time.

[E_T_V]

I'd have to check but isn't the original boost level something like 9psi?

[John S]

My boost gauge is not overly accurately but seems to point to 8 psi. I wondered if turning the actuator a few more turns wouldn't hurt. Is a re-profiled carb needle only needed for pressure above about 12 psi? I thought about turning it up between ~11-12 psi.

[E_T_V]

I'm not 100% sure on the limits of the standard needle but turning the boost up without more (enough) fuel will destroy the engine so not something to enter into lightly. Get it set up on a rolling road in my advice. (I still need to do mine!)

Chances are you may also cause the original clutch to give up too as it seems marginal at standard power levels.

[Sussex Pete]

I'd have to check but isn't the original boost level something like 9psi?

In checking the spec of the -13 wastegate adapter fitted to mine, I have found that the quoted pressure is indeed 9psi.

[Dave MGT]

Std boost pressure was 10psi if you were to re adjust to around 10psi no need to play with the needle. It's a bit of a pig to get to with the plenum in the way. Just make sure you crack off the lock nut first

Reprofiling the needle is not a hard job. But like stated above bit hit and miss without a rr or even better a afr gauge setup.

It's quite amazing how much faster they are with 14psi....different animal completely ! And not stressed at all