MurrayZA

Since I'm now running a VF23 on my PPP WRX (@16 PSI + full decat), what is the chance that the car is not fuelling enough
and/or advancing too much up the rev range and/or at high load ?

I am running no extra boost control at all - just modded the restrictor to give the 16PSI.

If this is the case - what gizmos should I be using to fix this
problem (AFR?) and keep the car safe ?

john banks

At 16 PSI it is likely OK, but you need to check it out. The other issue is that if your conditions are not too hot, you could extract a fair bit more out of your VF23. I would suggest using a manual boost controller at 17 PSI and logging everything as it is setup to check all is well. This will massively extend the boost curve to high revs, but this could also be the downfall hence checking it all out with datalogging/knock detection etc.

The standard ECU usually fuels very rich all the way up to the injectors maxxing out. For reference on my turbo (hybrid slightly better flowing than a VF23) at 6700 RPM at 17 PSI the duty cycle reaches 93% briefly with an uprated fuel pump - BUT I have leaned out the map - on the standard map it could reach 100%.

The advance however on the standard ECU is too much for my setup with top mount at 20 PSI midrange - and I have had to take some off otherwise it would det from 4500 to 6000 RPM - brief transitional det but undesirable nonetheless.

MurrayZA

We range between 0 degrees C and 35 degrees C here in JHB @ 6000 ft above sea level. So I want to be a bit conservative. I believe an MBC/EBC will really enhance performance - but what can I use on al 01 model to change timing and fuelling ? (Without spending
ludicrous amounts - i.e. New ECU) Would equal length headers help,
or add to the problem ?

john banks

Well with those temperatures and altitude an MBC is less ideal as it will give an absolute rather than relative boost target I think. So the pressure ratio at 16 PSI relative to atmospheric at sea level is higher so will increase charge temps and work the turbo harder.

Also I was talking MY99/00. I gather some 01's have smaller injectors. Also the knock control is completely different. A lot to be looked into. The US guys have bolted on turbos with standard ECUs and may be able to help you more - I am not sure if their WRX is identical to yours though.

Equal length headers will only push things further away from the original ECU map and should not be considered unless you are remapping IMHO, and then choose carefully. If buying them new might be better spending money elsewhere - eg intercooler.

MurrayZA

This is a catch 22... I can see why people just go the easy route and buy an STi... A delta ecu (alla ecutek) for the 01 is in DIRE need !

Pavlo

John,

After Bobs input on the ECU's load measurement, I detemined that the load is influenced heavily by the throttle position sensor. As a result, I am wondering if extra airflow due to a bigger turbo shows up as a very small increase in load. We have seen you can go off the edge of the standard map, but in reality I suspect that the air flow (and hence dynamic C/R) is higher than the map suggests. This could explain why you see more det with the standard turbo despite using similar areas of the map.

When you compared new and old, did you compare the actual MAF flow or the locations used on the fuel/ignition maps?

Paul

john banks

Paul that is a very interesting thought - thanks.

Often I have had the ECU hitting the last column on the map and only when I have extended the load to about $40 do I actually have columns I do not hit on the present turbo. So I did not collect enough data to know. However cars on the standard turbo do not seem to go above about $30 for load. So a 33% increase in load must mean there is still a substantial input from the MAF?

The conclusion I have come to is to see what load points the car hits and map them accordingly for detonation control. With slightly more exotic bits than the usual exhausts I find I am "creating" a lot of new load columns to give the control I want. Makes little sense to run a $2A last column when you are really hitting $40 and have a timing figure that is the same applying in between. In practive it is progressively retarding.

MurrayZA

I see myself buying a book here - something like: You and then ECU.

Pavlo

Jap performance map for pre 97 ecu runs $35 on the max load, this would have been mapped for about 15.5 psi on a td05, I think this is the same as the 260hp spec factory wrx, but don't have the map to hand.

Standard 94 map runs $2e for max load, mapped for about 10.5psi on tdo5

'96 Prodrive edition map runs $2f max load for about 13psi on a td05.

I think absolute boost is what you should be looking at when comparing air flow.

Comparing std with prodrive, as they still have catt'd downpipes, std induction, intercooler etc:

So $2e to $2f would be 2.2% increase in load for a (25.7-27.7 abs) 7.8% increase in pressure (and possibly flow).

Might be something in it, worth comparing air flow against load etc.

More work to be done for sure.

Paul

MurrayZA

Should I sell my 01 WRX, buy a 99 GT and get a Delta ECU ?
Would I be disappointed ?

Pavlo

naaaa

I am pretty sure the Delta ECU with 01/02 capability will be available soonish, they are testing at the moment.

You have a retailer near you that does it?

If so they should be able to sort you in the coming months.

Paul

MurrayZA

No retailer, but I have a degree in computer science and 8 years experience, so I think I should be able to get it right ! So far I've learnt the following: red blocks are bad. Seriously though -
I'll get and Apexi SBC-id / boost controller and then set up
a racing, conservative and standard map on the ECU to cope. I
understand the fuelling issues - the main thing for me to get my
head around is when advance and when to back off on the timing to
keep things safe. Oh, and then there is always the headers and 2.4
kit to come.... maybe.... either that - of just buy a flippin M3...lol (dont repeat that anywhere!!!)

Gerry Gaffney

Hoe gann dit meneer

Have a word with Pieter de Weerdt at Dastek in Pta on 012-347-1747. They are the manufacturer of the Unichip, which is compatible with your car. What this guy doesn't know about tuning cars, isn't worth knowing

When I'm out in October you could always shout me a Castle or two

Cheers,

Gerry

MurrayZA

Any time on the Castles.

I know Dastek do the Unichip - there just isnt one reliable installer in South Africa that I know of. Various tuners (not going to mention them) have made awful messes. Actually, one guy
that bought a unichip from a certain tuner got his act back and the
Unichip was taped to his ECU, not a wire connected and the
"test pattern" still programmed on the ECU.

Gerry Gaffney

Hi Murray,

I've heard that story also, makes me cringe (as did Pieter) I can't understand why people just can't do the job right

However, having lived & worked out in ZA (used to build the touring car engines for Toyota, down in Wynberg & lived in Midrand with my plaas yappie wife from Krugersdorp I know that there are some seriously clever & skilled tuners out there. As I say have a word with Pieter, tell him I sent you, & he will point you in the right direction. If it comes to it, I'll even map it myself when I'm out (in exchange for some braai vleis & a dop or two

Gerry

raybotha

Murry ,

Hi this is Ray from Jhb , just a thought but why dont't you just run racing fuel . I do , exclusively . At 4 bucks a litre its hardly expensive . The BP ones come in sealed tins so you can store them . My STI has never been to a fillings station in 15000 km's . I have had a car dynoed by Pieter D. and he is a very likeable fellow and does a money back guarentee but I would go for the ECUtek . Jaques from Pta can help too with all your questions , I've never met a more switched on and motivated "mechanic" in all my life . He does the Unichip and ECUtek's !

Good luck , hope too see you on the road soon . Ditto on the STI upgrade , I got tired of trying to make my my01 an STI .....

Ray

ScoobyDoo69

iTrader: (17)

MurrayZA, how many bhp do u think ur running??

ScoobyDoo69

BruceWarne

Murray, don't go messing around with the ecu settings...take it to a reputable shop like CRD, I know they do wonders...Hell, they have absolute wizz kids working there! Guys who should be nominated for the Nobel prize in physics! They were actually able to fit a unichip to my car, and extract 10 extra kW, without cutting one wire, or making one electrical connection...I did not know isolation tape could be used so creatively!

Seriously, rather do no remap, and run a conservative boost map, than do the mapping yourself, and f*ck it up...

I know of a WRC Blue STi calling your name - and now that you're sngle again, you have the cash to burn...

BruceWarne

Ray, where do you get racing fuel for that price?

MurrayZA

I think I'm running about 125kw atw. So, lets see... hmmm bhp.
Crikey. Well, that 125 probably translates back to 200kw at the
flywheel - which is approx: 270bhp. I know there is far more
possible - but I just want it to be safe. The 01 is very surgey -
I dont know if its retard or the boost mapping - but its not confidence inspiring.

As for u Bruce.... I'm looking forward to my STi 8 with sexy eyeballs.... lol. I'll pay my WRX off by year end and then asess
the best plan. I think the major major factor is that a bigger turbo has to have a 6 speed box to reduce lag.