fp advertised it is a 18lbs act., but they are more like 14psi actuator. Fp should adjusted these 18llbs actuator. They are really suck

 

when we first installed the fpred with 18lbs actuator, we cant get more than 25psi. After my tuner tighten the act. and screwdown the rod, we achieved 30psi. easy

 

Funny, I made over 38 psi with my 18psi actuator on a stock 9 turbo. I don't think it has anything to do with the actuator not being able to hold the boost. Like everyone said the most likely culprit is a boost leak.

 

hey i had the same thing happen to me and it turned out to be a couple boost leaks and one of the harder leaks to find was one of my injectors seals were broken so it was leaking threw there

 

And there are a million vacuum lines that can all pop off/dry rot, etc. I would go through and check them all, zip tying then along the way (I even super glue some of the looser ones and then zip tie over them).

 

I had to end up taking the piece off that connects to the flapper.
I used a grinder on it till I could thread it down to the bottom of the threads on the actuator arm.
I also removed that locking nut at the bottom so I could go further down.

I just got done doing a couple of runs and I was hitting 19psi.
The full boost was kicking in between 5k and 5500 and holding to redline.
I'm sure that this turbo can kick in boost much faster than that.

Thanks everybody for your input and advise.

 

Should be hitting full boost faster than that. I'd start doing a boost leak test now.

 

I will do that too, a friend has one that he made that I can use.

Think it could also be the tune?

 

Not likely. Again, I had the same issue as you did with my FP Black. I started with the boost leak test. Found a major leak on the outlet side of the intercooler. That started my boost to build faster but not enough. Then I adjusted the wastegate rod which allowed the boost to build faster.

You did it in the reverse order. So I think you will find a major leak somewhere either in one of your couplers or the vacuum lines.

With 2 guys working on it, you should be able to spot it pretty quickly. I'd suggest one of you get under the car listening to those couplers down low and the other checking on the vacuum lines.