I dont remember anyone asking this before but who did you purchase your kit from? I've got some info for you if we bought from the same people.

 

Update:

today i got the APS ST turbo exhaust installed .
and the result is

boost is 0.4 all the way to redline.

double checked the clamps and hoses... no leaks.
actuator is tightened to the max.. still no boost spike.

before with the blitz exhaust . boost use to go up sometimes ( 0.7 then drop back to 0.4 )
with the APS exhaust, its constantly 0.4 all the way to redline without any drop...



now what???i have tried everything.... shall i jump from Dubai burj????!!!!!

 

Get it tuned

 

Sounds like you had a problem before and now its fixed to me.

You were overboosting before now its controlled. What are the size differences between the 2 exhausts and what spring pressure is the wastegate running?

tom

 

the signal from the elect boost controller hooked up to the unichip?

 

i thought you guys said that the tune on the APS unichip is already solid enough to get some nice power !!!!!!


max was 0.7bar which is around 9psi( normal boost for APS st) and goes back to 0.3bar. now its all the time stuck on 0.3~0.4 Bar.

Blitz: single 2.75"
APS ST: Dual 2.5" ( APS claim that its a Zero back pressure )



No Electrical Boost controller. disconnected it, am using the Unichip boost solenoid.




any thoughts!!!!????

 

If you are having constant boost pressure to redline without spikes thats a good thing.

Either get the Unichip tuned and increase boost via the unichip or get an electronic boost controller. Sounds like you are just running off waste gate pressure to me.

-George
GT Motorsports

 

is your car is boosting without any power??

if that is the problem, i say go and check the flywheel installation.

 

My thoughts are throw it on the dyno, have your tuner try to adjust boost and confirm whether or not your boost control solenoid is working, or even hooked up properly. I would bet it isn't working the way it is supposed to. How many eyes have looked over the installation?

 

2 eyes,

i dont have much of an option in here.. its just 2 shops that knows about Turbo Z's in here.. and both checked the installation and confirmed that everything is ok..

is there a way i can check my self ??? How can i check that the boost solenoid is not right ??

 

Can't you just unplug the boost solenoid and just run off wastegate spring and see what you get.

 

two ways to check things out.

unplug the solenoid and see what you get as frankie stated. I will bet you see the same boost levels you are seeing now, futher confirming I don't think something is hooked up right (or not working)

also, get a small vise grip and pinch the vacuum line going from the solenoid to the wastegate. BE VERY CAREFUL with this one. Doing this will basically max out the boost level of the turbo. I say try this and watch your boost gauge closely and see if you can make more than .4 bar with your current setup. This will help narrow down the problem area. If you can't make any more boost, there is an issue from the turbo side of things... maybe a boost leak, bad turbo, ect. If you can, it is clearly a boost control issue

 

I can tell you one thing about the exhaust. I was running the TN kit with a custom y to mate to Borla exhaust which is 2.5'' and with no resonators I could only boost to 7.2psi. Then went with a full custom 3" with a resonator only, Sounds good but loud and was boosting to 9.5 psi off the 7psi spring. Went back to the muffler shop and put a Vibrant can on. Now I am boosting at 8psi and love the sound. I spent almost 2k just getting my exhaust right.

 

he has the proper exhaust on now. That is not of any concern now. The APS single exhaust is the best exhaust for his application.

 

I thought he was running some 2.5" duals.

 

he is running the APS single turbo exhaust specifically designed for his turbo kit... it is a y-pipe splitting into dual 2.5". You can reference APS' site if you are curious what it looks like

 

Yeah I dt know anything about my crossover pipe leaking, but mine has only 5K miles on it. I am currently replacing the whole wastegate setup aps has with an external 44mm tial that has a flex pipe in it, with an extermal dump. I cant imagine breaking the crossover pipe unless you kit the turbo which is under the K member... so I dunno. when you do install the cross over pipe one of the studs is EXTREMELY close to the turbo mount/merge Id replace it with a bolt. as for the level sender, yeah nissans are kinda screwey with it but its usable. I dunno, I think its a great kit, and its been very good to me, but some things like the WG setup sucks, and id put an inline oil filter to the turbo (Force Performance sells em.). Just my 2 cents...

 

thats the one im talking about. like Zivman said above. make sure the red wire from the solenoid is going to the unichip. when mine wasnt i boosted to 5psi and that was it, and it did hold 5 to redline.

 

dam

 

Yup, that's the easiest to overlook. You need to hook up the red wire to an empty slot of the unichip plug. If I remember correctly, it's not shown in the instruction diagram, but the instruction is written in the manual. If your mechanic installed everything just by looking at the diagrams provided by APS, he probably missed it.