ossett2k2

iTrader: (9)

I finally got my PLX Wideband gauge fitted along with a full decat exhaust which has a RCM bell mouth downpipe.
I haven't sorted my detcans out yet but have started tunning with a safe timing map. I'm using ESL and have tuned the closed loop to 14.7 and gradually going richer which is matching the wideband and fuel map,the problem is when I'm on wot the gauge is reading 10.0,which is the lowest it reads so could even be richer? I have 10.8 in the high load/rpm cells which is a fair way off what the wb is reading,is this normal and should I tune to the wb?
I don't want to start sticking leaner figures in the table(especially as I don't have the detcans set up yet).
I know in the manual it says the figures in the fuel map aren't exactly what you are getting but how far out would you expect them to be?

Cheers
Rich

piehole1983

iTrader: (7)

Andy has always said to me he prefers people to use the raw data instead of the converted values as they could be a fair bit off what the requested value in the map may be. In my experience the values measured by my wide band could be as much as 1 higher/lower than the requested value in the map. I'd do some logging with the wideband and adjust the map accordingly in raw data values.

Jaysz

I just use wideband readings
Mine maffless shows target of 20 at idle
Boost target same even with standard map shows - in places

bludgod

iTrader: (3)

On a newage car the maf scale table would be used to bring the fuel targets in the map in line with the wide band reading - using the raw data is better if your on speed density as I don't think you have a ve table to adjust.

If you are using maf mode then star adjusting the maf scale to bring fuel targets in line with wide band data, shoot for 11 flat and you should make decent power from it, if on speed density mode then switch the fuel map to raw data and tinker until your back on target.

ossett2k2

iTrader: (9)

Cheers,I am using maf so I will start looking at the maf scaling to bring it inline with the wb,I've not looked at maf scaling as I thought that was used if you changed maf/maf tube.

If I'm shooting for 11 and wb is reading 10 is it also ok to put a figure in until I match 11 on the wb? I don't have an EGT gauge fitted so it worries me a bit that I might be running too lean, I'm guessing I have to trust the wb for now.

The manual does say to use raw data when tuning mafless so will look into that when I get a IAT fitted.

bludgod

iTrader: (3)

Could be the maf scale in your rom is from a different maf tube though? If your in maf mode then trust the wide band and make the fuel table match by playing with the mag scale table. Watch out for closed loop/open loop transition and tip in enrichment, try and make 10 runs and then make an adjustment based on average data as you'll get a better scale from it.

11 is pretty standard afr for a cat less beast sso egt should be ok.

Is it also possible you have an air leak somewhere - metered air escaping after the turbo would leave you with a rich O2 reading as well.

ossett2k2

iTrader: (9)

Nice one,I really do need to spend a good day tuning rather than doing a run to work,logging and then making adjustments. Now I've got everything I need(just need to rig detcans up) And spend a few hours taking some decent logs.

As for a leak,is it possible an exhaust leak in the Exhaust center section(I think it's blowing slightly) would this cause some rich readings?

bludgod

iTrader: (3)

A leak at the exhaust after your sensors wouldn't affect the readings. A leak before the sensors would give you a leaner read as not all your gas is getting read.

If you can log the airflow difference over a wide range of maf voltage you might see a curve develop that could help you out in narrowing it down. If the scale starts to bend only at higher maf readings then it's probably maf scale. If it's across the board all positive or all negative it could be the injector scaling value.

ossett2k2

iTrader: (9)

Cool,you've given me a bit to think about there
I will have to do some more reading into maf rescale as I'm not 100% on this.

I'm getting 10 on the wb, rpm is 4300 , load 49 , boost 1.35bar(target) MAF V 3.83 and map requested AFR 11. I was going to input 12 to see if I can hit 11 on the wb but the maf scaling sound like the way to go but I'm not sure what the figure is on the maf table? At 3.83v the table reads 41857(this is the figure I'm unsure about)

bludgod

iTrader: (3)

the RPM readings aren't really relevant to the MAF scaling - only to the engine load calculation. Just focus on MAFv and then AFR error (target AFR and requested AFR). If your reading richer than the fuel table then remove some MAF air, if your reading leaner than the AFR table then add some MAF air.

This would be based on MAF voltage so if you can the easy way to do it is log your mafV and then calculate AFR error in excel and use that to help you make adjustments. Averaging the data over many runs will net you smoother more consistent results. If it turns out that the entire MAF scale is too lean or too rich then it's likely the injector size that actually needs adjusting.

ossett2k2

iTrader: (9)

Next bit of free time is going to be spent doing lots of runs and logging.
I'm matching the fuel map with the wb on lower loads and on the lower mafV from what i can see,just on wot and top end of mafV I'm reading rich.
I did input 11.8 Into the fuel map this morning before I set off and now on wot the wb is reading 10.8,didn't get chance to log but the car did feel happy and more responsive

bludgod

iTrader: (3)

yes but at lower loads are you reaching fuel target because of closed loop corrections? if you can - disable closed loop and run full time open loop then see what your corrections are like. Data overload is your friend here, you need to try and hit each mafv point a few times but not as part of tip in/tip out correction or cl/ol transition as these will monkey your fuel targets.

piehole1983

iTrader: (7)

Is it best to map the car in open loop then?

bludgod

iTrader: (3)

it makes it a little easier just as you don't have to worry about the ECU making corrections whilst your trying to makes things nice with the fuel map. If I had a strange MAF tube to scale in then i'd normally knock off closed loop to do the early maf volts then stick it back on so you can have more fuel economy whilst tuning in the rest of the maf scale.

If you can avoid tip in corrections though or incorporate the ecu's a/f corrections into your MAF scale then the ECU will also do some of the leg work for you.

The Rig

iTrader: (13)

Have you matched the Injector scale to get a close reading between wideband and the data AFR figures ?

I found once i did this, my AFR figures in the table were pretty close to Wideband readings once past closed loop, but when on full throttle at high RPM i had to knock a whole unit off the AFR data figures to then get the wideband reading correct, but a reading of 10 in my AFR table resulted in a reading of 11 on my wideband so i was happy with this setup, its only at around 5000 rpm and from about 50 throttle

Jaysz

Sure if mod car then load on table would change so targets be out
Are any of u maffless

bludgod

iTrader: (3)

with a maffless setup you adjust the fuel table in raw format as the converted vales don't line up anymore - with a maf setup just check injector scale and to get you up or down over the whole range in the ball park then fine tune with MAF settings

The Rig

iTrader: (13)

Maf and modded Here, i didnt alter Maf scale as i found Injector scale was enough to line up AFR and wideband.

its all good fun

ossett2k2

iTrader: (9)

So I will see what my fueling is like across the board and if it's all out then I will look at injector scaling then tweak the mafV table. I honestly thought that these 2 perameters were not to be touched unless I upgraded injectors or maf tube.
It does make things a little more complex but all adds to the fun
I will be going mafless at some point as I'm fitting an RCM cone filter and I have read they're not too maf friendly,don't know how true this is but I will run the filter in maf mode and see what happens to start with.

bludgod

iTrader: (3)

on a standard car running the standard map no you wouldn't normally need to touch MAF scale or injector scale as they would line up nicely. On your ESL the base map may not be for your car so some tweakings might be needed to get it just so.

The speed density stuph you'll be editing the fuel table manually so might as well switch to it now you have the wideband rather than tuning maf then tuning the fuelling again when you switch to SD?

ossett2k2

iTrader: (9)

It should have the base map on to match my ECU,or are they tweaked at factory for the specific car?
I know what your saying makes sense bludgod,I should be going mafless to save doing fuel map over again but that's a whole different ball game and I still need to learn a lot about the basic game,would also be nice to see what results I get from running induction kit with Maf on.
I will have a play with injector scaling to see if I can get closer to my fuel map before I tinker with the Maf calibration.

bludgod

iTrader: (3)

there would be a specific map for each vehicle applied at the factory - things like maf scaling and injector settings would change dependingon wrx/sti/year etc. The different MAF types over the years will have different MAF scales, you maybe have changes in the injectors are probably spot on though as you'll have the 440's or 550's most likely.

Maybe worth checking with ESL which basemap they've given you and if it was set for the MAF type that you have - could be they just have a generic ESL basemap that suits most applications to get your car up and running long enough to go to the tuning shop.

ossett2k2

iTrader: (9)

Cool,that make sense,I was assuming that ESL put the map from my car as a base,the ECU is a 1S and used on the my97 WRX but my car is a TypeRA which have 440 injectors and orange label Maf. Also has a 5th injector but I don't think that is in use?
I'll have to do some more research and get in touch with Andy at ESL.
Any suggestions on where to get hold of a v3 typeRA rom to compare?

ossett2k2

iTrader: (9)

Having a look around and came across some info on the Andy Forrest site saying 'Most 93-98 cars have 380cc injectors which at standard pressure are rated at up to 300 bhp'
A few other sites say 380's too. If this is correct and my ECU thinks I've got 380's in when infact I've got 440's I'm guessing this would give me rich fueling but wouldn't it also run like a pig?

Neil XR

iTrader: (1)

380cc are grey, 440cc are yellow

bludgod

iTrader: (3)

380 to 440 is only like 16% bump which is below what the ECU can adjust for - yes it would be a lot richer on your open loop fuelling than you expect but closed loop the ECU should be able to pull it back in line.

As above, physically eyeball your current squirters and see what you've got

ossett2k2

iTrader: (9)

Mine are definatly yellow 440's and standard on my car but what I don't know is what the stock injectors are on the v3 WRX(non typeRA).
Both WRX and WRX typeRA use the 1s ECU so does this mean both cars would have 440's ?
Before I set off to work tonight I will scale my injectors from 1.0 to 0.86 and take a couple of logs.

bludgod

iTrader: (3)

at least the changes are live so it shouldn't take much tinkering to find the right value assuming the MAF scale is correct.

when you make a change just reset the ecu to clear the existing fuel trims and go drive around for a few miles and re-check the fuel trim table - they should start to balance out fairly quickly if you can get some steady state closed loop cruising on the go.

ossett2k2

iTrader: (9)

Matthew has just confirmed that his V3 WRX (non ra ) has the same set up as me,440's and same Maf and has the same ECU which must mean the only real difference with my car is the short ratio box,I can only assume we have the same base map therefore my injector And Maf scaling is correct. I'm still going to have a play with the injector scale and see if my wb readings are any closer to my requested AFR's

bludgod

iTrader: (3)

coolness - but if your sure the maf and injector scale are correct - are you sure you've 2000% ruled out any vac/boost/exhaust leaks? Any gap in the chain between MAF reading and o2 reporting could give you grief.