So last time, z4 ecu, panel filter, decat and got 250bhp, had a few issues with it running 0.8 bar even after the Z4 ecu went in, it seemed to get better after but i bought a dawes device anyway.

So i ran it again today with dawes device and apexi induction kit, upped the boost to a solid 0.9 and got 267.1 bhp see the garap here:

http://i86.photobucket.com/albums/k1...egtt/graph.jpg

It has the new graph plotted against the old 250bhp one.

its pulling really hard now and feels good!

Dave

 

Fueling was spot on 0.8 (Lambda) getting slsight richer at top end.

Dave

 

Problem solved then.. Cool..

 

yeah its going really well!! pulls hard right up to the red line.

Front mount and some sort of electronic boost control next!!

Dave

 

Curve is a bit wierd though with a bit of a dip/rise at 4500rpm.
Did Alan Jeffries comment on that at all ??

 

It is weird, The odd thing is the first graph line was on the standard boost control solenoid and the second is on the dawes device, yet there the trend of the line is very similar, so its not boost control, I can actually hear the turbo spin up at the 4500 mark when the boost creeps up again.

I was thinking maybe the actuator?

what do you think?

Dave

 

Here is the boost / Lambda graph

http://i86.photobucket.com/albums/k1...Dyno2aedit.jpg

The highest 2 lines are the 250bhp and the 267bhp boost plots, it shoots straight up to the 0.8 area then climbs again to the 0.9 zone.

I wonder if it is the actuator and if this is why i had a problem getting over 0.8 after i put in the z4 ecu?

Dave

 

If running a Dawes I doubt it's the actuator as the actuator won't see the boost until the dawes lets it through.

It's almost as if there is a slight leak somewhere, acting as a slight bleed valve once above 4500 rpm.

 

well once the front mount is fitted i'll eliminate some hosing and the intercooler.

 

Mmmm...

Since I fitted my Dawes I've noticed similar with my car. Boost builds nice, then at 4000-4500rpm power drops very slightly and then a kick in the back and off you go. I've not thought anything of it till now!!

 

Hmmm acting very similar to me then!

The standard set up shows a better boost curve with it starting strong and then dropping as the revs rise. I guess its just the way the dawes deals with the boost ?

Is it worth putting a restrictor in the feed hose to the dawes ?

Dave

 

the dawes does have a small hole drilled in one end..very small infact
if you open this up a bit it should prevent the spike. butyou may have to tighten it up a bit to get it to hold the desired boost.

the graph clearly show the dawes spools at similar rates to the ECU control, so why bother removing the safety net the ECU can provide....just my opinion....

 

What safety net is provided by the ecu?

Dave

 

Limp mode....

If ECU detects a sensor fault i.e MAF it will put it into limp mode.
This won't always throw a CEL and inthe instance I saw at the weekend can cuase the AFR to be all over the shot and quite lean.

The Dawes bypasses the limp mode i.e still allows full boost.....I'll leave you to work out the rest.....

 

So your saying no point in having any other boost control other than the standard ecu ? As any other boost control will bypass the standard solenoid and thus the ability to automatically reduce boost?

is that a common view?

Dave