Please take a look at these graphs and tell me what you think....its not holding boost and the fueling is all over the place looking for advice and a cause of problems.

jay

 

what spec \ car you running - is it mapped

 

its never been mapped
95 wrx
SB ecu,chipped(no idea what what chip)
full decat
fmic
apexi IK
walbro 255
Im looking for info on the boost/fuel issues

 

dawes device would smooth that right out TBH

mine was the same on standard boost control my97

 

what about the fueling,fuel reg?

 

That looks like a faulty boost control solenoid to me...As Stickymicky said a Dawes device would sort that out although a replacement electronic boost controller would of course be best way to go...As for the fueling it is bound to be all over the place while the boost is up and down...You would probably find that when you have good boost control the fueling would begin to make sense...A pressure reg would give the tuner some control over the fueling although again the right way to go would be to ditch the SB ecu and fit an Apexi and get it mapped...With your current spec I would expect to see 300bhp plus with all of these done correctly...

 

I would say it's due to the SB ECU, which is out of a STi RA. For the following reasons.

Despite whats been published in Japanese Performance mag (regarding both their Project RA). The SB ECU comes 'chipped' from STi. If the Chip has a big long number on a white label it is the standard STi chip.

The Boost duty on the SB is very high for the Boost Target compared to any other ECU (W6, U8, Z4 etc..etc..) It runs around 70% duty rather then around 55% for the Z4.

The SB ECU peaks a little higher but at the top end they are quite similar. So you would expect the duty to be similar (I have never got to the bottom of the reasons behind this anomaly)

If the SB is not in an STi, then this would be the reason for the boost overshoot and instability.

Below are the Boost & Duty maps from an SB and a Z4 for you to compare.





You may say..."the SB runs higher boost hence the higher duty".
But I only run around 65% duty in my 16.11psi maps.

The fuelling of an SB is also quite lean compared to the other ECU. This would be how the STi runs 275ps rather then the 260ps of a similar aged WRX. This fuelling can be seen on you RR plot running in the 12's, so it looks OK for an SB ECU. This can also be seen in the SB fuel map I have posted below.



Basically the SB map is not suited tou your application.