W6 ECU TO Z4 NO CHANGE!!
 

I just fitted a Z4 ecu to my MY93 WRX. It replaced the W6 that was in there which I think is the standard one. After installation I performed an ecu reset and I have a tank of optimax. I was hoping for a noticable change with increased boost to 1.1 but there is no real noticable difference and the car is still only running 0.7 - 0.8bar boost. Is that correct? Should I expect to see more like 1.1bar from a Z4?

nope, u gotta either fit a dawes or a EBC too increase the boost, ecu will allow it too b done not actually do it i think... but i may b wrong

urm well this i smy old ecu, and it boosted on mine and all i had was a 3 port sel?? no boost controller or bleed valve ect, so is it down to actuator arm tightness?

Z4 boosts at 0.876 bar, so you won't see an increase up to 1.1....
The main advantage of the Z4 over your previous ecu is that the ignition, boost and mixture are controlled better so you can expect more power and better fuel economy (ha!).
Drop a dawes in there and set it to 1.0bar for a bit more of a kick.

edit: I see you're getting 0.7- 0.8 bar boost. Is that the low gears or 4th and 5th? If you're not getting close to 0.9 try an ecu reset or look for an airleak.

get yourself a td05 for a real benefit ;)

That never even occured to me.... Is it a TD04 in the earlier salloons? That might explain it....

93 wrx should have a TD05 16g as standard, unless it has been changed for a TD04 by someone.

yer should have a 05...ok this is weird, ca someone tell me how mine was running such high boost then, i had no boost controller or any other device i noticed, so how was i getting this power out of it???

Cheers guys. The turbos the TD05. I think I'm seing just over the 0.8bar mark in most gears at the mo.

Ill check for an air leak, but could it be Shanes decat downpipe thats helping the boost get up to the magic 1.1bar?

Have you ever seen inside your ECU? There could be a chip lurking....

Theres no chip in it. I bought the ecu off Shane, his car ran 1.1bar with it, mine runs 0.8ish. We're trying to workout what would cause this difference. As far as I know the only difference is that I think Shane has a decat down pipe and full system, where as my exhaust is still standard.

did u say ur getting s decat/system? let us know when its fitted if it goes up...the only other thing it can be is my actuator arm length

The new exhaust system is getting fitted tomorrow. I'll let you know the result. My boost gauge only goes up to 1 bar (I've got a new one coming) it'll do for tomorrow though, it'll be good enough to let me know if the decat ups the boost. Is the actuator arm adjustable?

Z4 should boost to 12.7psi, 1.2psi more then a W6

If you were getting any more then this, then maybe the Restrictor Valve is missing from 3-port return hose.
Or if an induction kit is fitted the 3-port return hose may of been taken off altogether.

New exhaust is fitted after 5 hours labour because the bolts on the turbo flange were completly seezed up. Definete improvement in torque and spool up but no change to boost levels. I'm getting around 0.7-0.8 when accelerating through most gears still. Weirdly though I'm getting about 0.875 if I put my foot down in 5th. Should it be boosting higher now it has a full de-cat system? I'm thinking I might just fit a dawes device and run it at 1 bar but is that safe with the z4 ecu?

at 1 bar the fuel cut will not be hit so yes it will be safe as the ecu can control the fuelling to match.

speed, have you got your standard airbox ect still fitted? just read what scott put as i had a hks filter and have just check and one of the pipes was blocked with a screw, so looks like he was right about how u get the extra boost, if you have the air filter already sorted u could try the pipe thing first?

Yeah I've got a pipercross induction kit fitted. I think all the pipes off the 3 port solenoid are being used but I haven't traced them all, which is the return pipe? I did notice that there was an open pipe coming off the induction kit when I got the car, it looks like there should be a pipe on it. Do you know what thats for? I blocked it off as soon as I noticed it.