The Car
93 Civic SI hatch
stock D16z6
Greddy blue box, stock injectors.
Full greddy turbo kit (TD04 turbo just oil, not water cooled.) Engine temps are hot!
skunk 2 exhaust

only things i could think would be the problem.

the 2.25 exhaust
the 2" downpipe
Greddy Blue box? im not familure with this setup.

We took out the XS manual boost control and it did the same thing with the stock internal waste gate.

Boost will run 7psi in first
second hits 7psi at about 3500 and then drops to 5 at 5+
same as 3rd.

any sujestions?

 

side note. we will soon be upgrading to Urberdata and DSM 450cc injectors.

 

When u had the Boost Controller in did you try uping the boost past 7 psi?

 

we might have hit 8psi using the boost controler at the track, but we didn't want to bump it to 10 or anything because he bought the car with the bluebox already installed and we don't want to blow anything. as soon as we get urberdata in their. we will boost it to 10psi.

 

yea we will

 

we are going to run the vac/boost line to the waste gate from the intake manifold instead of off the turbo to see if that make any differance. also going to check for a boost leak. anyother segestions?

 

your exhuast system is not flowing enough so trying disconneting the end of the dp to the exhuast and see what is happening or the intenal wastegate is just not strong enough and is leaking boost

 

definatly going to run it open downpipe and see what happens. any other sejestions? if the exhaust is the problem i can see me welding in an E-cut out very soon. also does anyone make a 3" a/c compatable downpipe for this setup?

thanks for the replys.

 

are you running a filter? i had the same problem, i hacked up a filter and used it as a screen. Boost will drop. So now i took off some material and it holds at 6psi.

 

we pulled the filter off and made a few runs. no differance.

steps for solving this
Run vac line from intake manifold to wastegate. instead of direct off of compressor side of turbo.
Test for leaks.
Run open DP.
Try new filters and run no filter to try something new.
upgrade to Urberdata ASAP
run 10psi

any thing else

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bmcc72 &raquo;</TD></TR><TR><TD CLASS="quote">definatly going to run it open downpipe and see what happens. any other sejestions? if the exhaust is the problem i can see me welding in an E-cut out very soon. also does anyone make a 3" a/c compatable downpipe for this setup?

thanks for the replys. </TD></TR></TABLE>


If anyone makes a 3" dp let me know. i think that greddy on is crap!

 

if you're going to put the boost controller back in, maybe u should try to mount it closer the the vacuum source on the intake manifold, if that makes sense. if not, connect the wastegate directly to the intake manifold with the least amount of vacuum line as possible and make sure you zip tie the ends so there are no leaks whatsoever.

 

You know thing is, i hit 8-9 pounds, then falls back off to 6psi and holds there. Then next gear same thing happens, and on 4th gear it holds at 7psi. Maybe because mine is auto. But almost same situation, nonetheless maybe its just that our wastegate springs are old. My turbo was used, don't know about yours.

 

im am using the b-series kit from greddy - same issues couple things--

1) i am using an N1 exhaust which is also small piping- could be the issue-

2) greddy was stupid when they made these WG actuators-- they welded them to the flange instead of bolting-- this weld causes the rubber seal in the actuator heat up and break easy-- not holding over-6-7psi

I suggest
1) new exhaust
2) new actuator

the other problem is the placement of the WG itself-- its too close to hte exhaust wheel and that causes it to open too early--

good luck on the fix, ill watch this to see what happens.

 

I had the same problem losing boost after 5Krpm. It turned out i had a crack in one of my rubber couplings. There is a post on here about how to make a compressor tester for you pipes. Search and you will find it.

 

yeah i posted a picture of how to make the boost leak tester.

we will be checking that as soon as we both get time off work.

 

yay for ben helping me fix my ******

 

yea, mine's auto and read 6psi till a gear change and then read +2psi for every gear after that... i think my gauge sux. it will read + or - 3ish psi depending on weather conditons