John

thanks again for your explanations.

By comparing the values I've stated with those of the Link table it looks ok, meaning in the spool up zone no problem and quite rich at top end. Considering it's an off-the-shelf ECU not too bad especially as you get around 340-350hp with this setup. Anyway a Lambda link seems to be a very sensible option.
What is your opinion about it? What kind of values does your PPPed car produce?
Very nice, the new year's still quite young and already learned something new!

Cheers

Mike

 

Lambda link seems a good move. I take it you saw my thread on building your own in drivetrain a while back? If that floats your boat...

Apart from during spool up I get lambdas pretty much like the link ECU targets above for various boost zones.

I think I may need to put my 10 bar lambda display back on and see what I am actually getting during spool up - it is off my three led display at the moment... I just don't know what I should be seeing during spool up in terms of richness. Since the select monitor showed good ignition advance all the way (I went from 2000 to 7200rpm) I doubt it is lean or lean enough to knock.

Theo also mentioned to me that MY01's have SMALLER injectors. Good thinking on Subaru's part there - I wonder if this is why the I-club guys have all this paranoia about running more than 15-16 PSI on stock ECU - because of soaring EGTs.

[Edited by john banks - 1/1/2002 10:59:58 AM]

 

Have to read through this thread concerning your own Lambda link.

Will come back later.

Cheers

Mike

 

http://www.scoobynet.co.uk/bbs/threa...threadid=57428

 

hi john, mike
happy new year

the lambda link or any lambda display is very important for any moded car i think.

if you gently go through the boost and the revs you should see the lambda readings increase gradually, ie 3-4% 5psi moving 6%10psi and 7-8% all the way to what ever target you are running.

however if you floor it from any part of the revs low/high that should activate the ECU enrichment facility and you should get 7-8% all the way.

running 5% to 3500rpm is kind of marginal and i would not really worry to much about it. i have seen engines mapped on a dyno where the operator ran the egine at 5% in the low revs as you should get more power that way. as long it is rich at the top end and not knocking at the 3000rpm then to should be good.

sam

 

hi john, mike
happy new year

the lambda link or any lambda display is very important for any moded car i think.

if you gently go through the boost and the revs you should see the lambda readings increase gradually, ie 3-4% 5psi moving 6%10psi and 7-8% all the way to what ever target you are running.

however if you floor it from any part of the revs low/high that should activate the ECU enrichment facility and you should get 7-8% all the way.

running 5% to 3500rpm is kind of marginal and i would not really worry to much about it. i have seen engines mapped on a dyno where the operator ran the egine at 5% in the low revs as you should get more power that way. as long it is rich at the top end and not knocking at the 3000rpm then to should be good.

sam

 

Hi mates

thanks for your inputs.

It looks like I'm on a good path. After surfing the whole afternoon to gather information about the A/F mixture it also looks good at peak torque. It runs almost 7% CO at this point which is should be sufficient. Topend quite rich with around 8% CO so safe.
Nevertheless I think any device to measure lambda during driving seems more than sensible. Just have to find out how to fit my dad's MOT tester in the back of my car (just kidding)!

Cheers

Mike

 

If I floor it over 3000rpm I get enrichment. On a full throttle run from 2000-3000rpm the enrichment certainly lags behind the boost compared with 3000-4000rpm, but this seems OK from what has been said.

 

John, Sam

maybe a dumb question but setting up the MBC would you recommend doing it in 3. or 4. gear? I think in 4. gear load is even bigger so maybe that's better?
Shame I won't do it till March (weather, exams and back problems) but I love those discussions.

See ya

Mike

 

hi mike
i don't know about the MBC but with the link ecu for example it was better to set up the boost in high gears. as you said there is more load on higher gears also there is more exhaust gases etc.. the boost will rise quicker leading to more chance of over boost.

when i had link on my subaru i used to adjust the Waste gate cycle, rpm and sensitivity to give a little of over boost in 4th gear. but this is a little different than the MBC i think. saying that i never used to floor it in 5th gear as it is very tall gear and was only used on the motor way.

 

I go with Sam and set in 4th gear. With a Dawes with a 1mm extra bleed (as per other post) there is <0.5PSI difference in held boost between 2nd and 5th on a Scooby, and it just quickly finds held and doesn't peak with this setup. A setup using a duty solenoid will have considerably more variation between gears unless it is mapped for each gear.

 

Sam/John

The duty cycle is indeed longer with the Sports ECU than with the standard ECU and so accentuates the boost problem I've encountered meaning unstable boost. The MBC should solve that by bleeding a steady amount of air.

According to your recommendation I'll set it up in 4. gear. My boost gauge will be very useful as you can record the last 40 seconds, shows peak boost and you can set a warning when a certain level of boost is exceeded. Very handy.

The other thing to watch is probably the level of boost when driving part throttle as I don't want the EGT going through the roof. Any advice on this matter?

Cheers

Mike

 

A bit of a bleed helps on the Scooby. The US guys go on about it a lot, but they have a different ECU - most also have a full set of cats including a preturbo uppipe cat. Scooby fuels using the MAF for fuelling so I think it just compensates quite happily at least on MY99/00. If your fuelling is RPM and TPS driven (don't know if this is common just thinking of possibilities) it could get into problems. If it is MAP or MAF based I would have thought it would cope better.

 

John

the fueling is MAF (Karman) based on the EVO. I'll run a cat but this is the same as used by the factory WRC Focus, Lancer and Peugeot. It's located in the centre section. It's a 100 cell metall cat so almost no restriction.

Contrary to the Scoob the EVO doesn't have a MAP sensor which is e.g. needed when fitting a Motec. The GEMS implant BTW can use the MAF on the EVO.

Generally I wonder why so many people buy EBCs when you can get the same from a manual one. As long as you need only one boost setting, don't need gear related boost (powerful RWD car) and don't mind fiddling a bit the MBC are good VFM. Look at John he achieved very good results and found out loads about the way the ECU works on his car.

Brilliant stuff John. I've to hide those topics from my mate Dowser so he won't fit such a valve on his similar modded Scoob

Cheers

Mike

 

hi mike

do you really want value for money and willing to fiddle with things your self there is even an easier way to achieve the same results.

you can actually adjust the wastegate actuator spring via adjusting the arm to get it to open at 17,18,19psi etc... quite easy to do on a scoob, remove the C clip connect the WG rod to the turbo, un wind it few turns to the disered boost and hey presto!!!!! cost= big fat zero. the only thing is this way you will keep the soleniod so the ECU will have a little control over boost in the case of a problem. unless of course you are like john and myself who will run the car with a little lambda display on.

the problem is with the standard ECU you still use the AFM which is a very delicate sensor prone to failure, if this goes faulty the ecu will limit the boost in the limp home mode, with the Dawe you will loose that completely ( also with adjusting the waste gate actuatar) and the result could be serious. this when a little bit of knowledge can be dangerous. so people reading this thread should be aware of this little minor complication

sam

 

Sam,

This was the thing niggling away at me at the back of my mind about the Dawes. What would happen if the MAF failed and the ECU went into (tried to go into) Limp Home Mode with a Dawes fitted?

Ta,

Matt

 

engine check light will come on when your MAF is totally ****ed, but they are also prone to get tired not enough for them to trigger the check engine light. i have read couple of thread on the past about some cars running poorly and it was found that it was the maf sensor.

but it is not only the maf it is just an example how about the map sonsor? how about a blocked injector surely there is a way the ecu controls boost when things go wrong. the soleniod is the way the ECU controls the boost it is there for a reason. to go back to the original post i am sure it would have been easier for subaru to use some thing like the dawe to control the boost. actually make that every other car manufaturer for that matter.

don't get me wrong i am not saying the dawe is crap and you should not use it, i have ordered one myself but common sense should be applied.

there is no such a thing in life as a free lunch is something i greatly believe in

just a thought anyway.

 

Also does limp home mode not limit you to 3000rpm?

I did think if I made an EBC I would consider a tap off the supply to the check engine light so that the boost controller would be disabled if it came on.

 

Just for info -

I had a partial MAF sensor failure on my old legacy once, it was covered in oily crap sucked in through the filter.

I was running a superchip at the time, can't remember for sure but i think the engine warning light did not come on. The car seemed to be running very rich with misfires and eventually stalling unable to re-start, probably flooded.

The point is that for this particular failure the MAF over read the air flowing past the sensor (i can only assume it was due to the oil contamination cooling the filament), putting the mixture very rich. I think (but i may be wrong) that apart from inconvenience, this would not damage the engine.

The MAF was cleaned and worked fine with no residual problems.

I'm just wondering what would happen if the MAF went completely open circuit and burned out? would it run rich or lean?


Rich

 

Sam

these are valid points but the Sports ECU doesn't anyway have a fuel cut so it's on you to safe the engine.
I know that the MAF is a delicate sensor. For this reason I run my car with the relocation kit including the RA panel filter. I'm no fan of the cone air filters at all due to the higher possibility to contamine your MAF due to bad filtration.
So far I haven't seen any EVO having a MAF failure. I know this doesn't mean anything but at least on the EVO they seem to be more reliable than on the Scoob.
A lambda link will be definitely on my menu. As the car gets faster and faster I need a passenger to monitor all those gadgets soon!
Additional mod will be also a selfmade cold air duct which should improve things further!!!!!!!!!!

Cheers

Mike

 

If it went into limp home mode would you not get a check engine light?

Would you not have the same problem with any boost controller?

[Edited by john banks - 1/2/2002 9:19:28 PM]

 

But if the ECU goes into a protection mode it is either in it or not, and I would hope a CEL would come on. If the MAF is damaged but the ECU doesn't know then a non-Dawes user could be in trouble as well? Same with any engine failure I would guess? Maybe one reason I am happier to be back on a panel filter. It doesn't seem any slower. I hope the ITG holds onto its slugde!

Agreed we are eating in to our safety margin and your points are very valid.

Subaru could have easily used a ball spring, and retained safety by just intalling a bypass solenoid if it all went pear shaped.

But better still I think they would have just put a decent solenoid duty cycle map in to start with and we would all have had about 250bhp out the box even with all our cats. But maybe they would have more warranty claims for clutches/gearboxes/turbos etc. And maybe the engines would not do such interstellar mileages, and the insurance would be higher.

I am not entirely convinced that a lot of the aftermarket ECUs have anything like the level of control, refinement and safety features of the original ECU. It seems for example that the Unichips duty cycle is fixed and has no feedback and no TPS mapping and only soon are they moving onto 3D map using TPS and PID loops. The original ECU did that from day 1.

But I still think the Dawes is the quickest way to spool up a turbo possible hence it stays It has at least as many pros as cons. The consistency and control of the boost are far better than OEM despite what a lot of folk say. 2nd gear is very similar to 5th in the amount of boost produced. It is very easy to set up. It just doesn't have a fancy display, but seems a lot less spike prone than many EBCs.

[Edited by john banks - 1/2/2002 9:52:52 PM]