A New msp owner that needs less boost

asmo 03 mp5

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2003.5 titanium MSP
I recently picked up a 3.5 MSP that had a rod through the block, I just want a fun daily and don't have funds for a forged motor, so I picked up a used 2001 626 engine and put that in the car.
It runs ok but my problem is it boosts 11-12 psi. The Mods are weaponr hard pipes, sls catless midpipe, ETS side mount, injen intake, unknown sized deatchwerks injectors, and the 626 intake manifold.
I know the boost is too high and need it lower, like 7-8 preferably, how can I do this? right now I have no boost controller just the vacuum line off throttle body to wastegate.

I have stock midpipe would putting it back on help?

And yes I know a lot of people are gonna be like WTF, why do you want less boost.
But I need this car to last awhile and be somewhat reliable as it's my only transportation.
 
you prolly just need a wastegate actuator rated at a lower psi. do you have the stock turbo on? there's a wastegate actuator made by ATP that's stock replacement for our stock turbos rated at 7-8psi.

PM'd you link to product
 
I have stock turbo, and stock wastegate, is the stock wastegate adjustable?
 
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Stock wga has gone bad is why it boosts to 12. Buy the atp one to replace it with. That's prob why it had a rod through it lol.
 
Esp with full boost at 2200 rpm. Sucks having boost just leaving a stop light.
 
No it doesn't, lol. I love my MSP, the turbo is the whole reason I bought it so i'm going to enjoy it
 
Thanks guys,
I pulled the vac line and was able to blow threw it,
this also explains my fuel cut issue.
Gonna order a new wastegate asap,
The one ATP lists as 6psi but on cross over they list it as 7-8 what gives?
 
not sure. but majority of people hit 7-8psi with the ATP WGA on our cars.
 
ATP actuator model: "....11B" is the direct replacement for the OEM actuator. Find that actuator on their website and notice that it comes with an adjustable rod length option. Sometime in the past I asked ATP about the max range of this adjusting rod. Here's the email exchange:

"
My question:

> I meant "how much steady boost (after any spiking) can I expect
> from this product if I adjust the threaded rod to the maximum preload"?

ATPs reply:

The adjustable version of this one will give you the 9-10 psi steady
target boost if you're willing to tolerate a little spike.
"
 
when you change the wastegate actuator, put in a check valve so it lasts longer. look through my started threads, you'll find it. $2 belt and suspenders fix.
 
With the atp actuator my car hits 7psi but it still has issues, as soon as it goes over 5 psi it surges, and cuts in and out.
 
Disconnect the battery and clear the ecu. Prob done some bad learning. Make sure plugs are gapped correctly too.
 
Fuel cut doesbt usually happen unless the air temp is extreme. But ssafssafc is considered standard equipment for a mildly modified msp anyway.
 
I put the car back to stock,
my only mods are the atp injen cold air and a sls midpipe.
The car came with ssafct and I sold it.
 
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