Ecu Been Fiddled With, But Where?

[MBS206]

Alrighty, so I threw my car on the dyno at the start of this month, and it rattled off a nice and imppresive 248RWHP (185.3RWKW) on 10/11PSi, with a 3" full exhaust, FMIC, pod filter with custom air box and a 35degree day

Now, most would be happy with this type of power, BUT, there's a hole in my fun, as follows:

As you can see, there's a bit of a torque hole!

Now, I took it to my trusting mechanic at Wollongong Motorsport Centre (Same place it got dyno'd) and we decided to have a look around at things, first up, the CAS ISN'T a standard R33 GTS25T CAS. Weird.

Secondly the ECU map for ignition and fuel, is different from stock. (We hooked up Consult)

So now, I've gotten the shits, I want that extra power, I don't want a pinging motor, so I'm ordering in a new aftermarket ECU to install later, but, curiosity is killing me, and I want to know what part has been changed in my ECU. So, I'll throw some more pics up of inside the ECU

Please note, no matter which way the CAS was moved, the power got worse.

[paulr33]

its most likely stock maps, if it was remppaed you wouldnt have those wonky curves

[MBS206]

It's sitting too lean for stock map, and actually VIEWING the maps and comparing them side by side with stock maps, they are vastly different.

Way too much ign timing I have been told.

That's on good 98RON fuel too, and each time the graph dips, it is pinging.

Edited February 25, 2007 by MBS206

[Birnie]

Well, if there's pinging, the ECU retards doesn't it?

It has the sensors for that reason and i thought that's be the answer.

Also, remember they self learn too..Mine had to re-learn for 10mins driving after changing the dump pipe. I thought i was screwed as it was behaving really bad! and then it all came together.

Just get the Power FC before you waste any cash at the mechanics. That'll solve all your probs

[MBS206]

1) I'm not touching a PFC.

2) The cars been like this for ages.

3) Theres a difference between permanent base maps, and self learn trim maps.

Secondly, new aftermarket ECU is being ordered in around a week and a half fingers crossed!

Sorry if I'm sounding rude, but all of this has been gone over, and zero money has been sent on chasing things. I'm just trying to find out what has physically been changed inside the ECU.

And yes it does have the sensors to remove timing to avoid pinging, but the problem is, it can obviously make the power, it's been tuned to make more power and torque, but the thing I want to know is, WHAT has been changed? :S

I'm not after changing it back really, I just want to know what the people have changed, as mid rang and low range has a shit load of torque.

But yes, new ECU coming soon.

[R31Nismoid]

Well put a genuine stock ECU on and see what happens.

Alternatively use a genuine CAS aswell.

Its possible to remap the stock chips, it justs isnt feasible here in Aust where prices are not really worth it

[TSL]

It looks completely stock standard.

Edited February 25, 2007 by TSL

[MANWHORE]

that's stock as a rock. You see how it's got the two big chips on the left?

The upper one is the cpu with maps inside. If it's remapped, it'll hvae a chip socket.

[MANWHORE]

Are you SURE that your tuner has the stock maps?

Use consult and download the maps, and post up an image of the fuel and ignition map.

If the ignition timing drops off to about 8-9 degrees at the end colum for where the ecu hits rich and retard, it's the stock map most likely

[Spooner]

Hey guys

please excuse my ignorance here, but what ia a CAS? cant find anything on google.....

[MANWHORE]

crank angle sensor - adjust ignition timing with this

[Link]

We can always swap ecu's if you think yours has been fiddled with and see if it does the same...

[boot_it]

crank angle sensor - adjust ignition timing with this

technically its a

Cam

Angle

Sensor

[Beer Baron]

it's a stock ecu... end of story.

edit: as for the comparitive lean running it could be a number of things. poor fuel pump, AFM problem, injector problem, O2 sensor problem (used for the reading) etc. or just I have seen some cars do run lean with the stock ecu and increased boost. it happens.

[RB30-POWER]

the torque hole is so typical of the standard ecu based airflow limiter settings in the ecu.

i will agree however, those afr aren't to bad for a stock ecu at all, usually once you see that torque dip where it cuts ignition you will see the afr go down to 10's.

could just be the pump on its way out or other cause of low fuel pressure.

[MBS206]

It hits 24degree ign timing on the map on consult. No 8 or 9 degrees.

I'll get them and download.

When it hits the 24 degrees ign timing, it pings on the dyno (And road) and retards out, but not via the map.

[TSL]

Yes the stock map has 24deg of timing at 5600rpm in the 2nd highest load column.

The dyno curve is very much typical of a standard r33 ecu. The engine is obviously pinging quite badly and the ecu is savagely reducing the timing when it detects knock.

Naturally advancing the base timing via the cas will only make the problem worse. Reducing the timing will of course lose some power but will go some way to fixing the problem.

Any competent workshop who has worked on a few r33's should be aware of all this.

Edited February 26, 2007 by TSL

[MBS206]

Supposedly it's pretty much well been changed from what I've been told.

And the timing was already sitting where it was meant to be supposedly.

Ah well, hopefully this weekend I can throw the full aftermarket ECU in, depending when I get it delivered.

Then I'll keep all posted on the power and progress.

[MANWHORE]

I'm not talking about peak timing mate. I'm talking about timing in the last colum when it hits r + r

[MANWHORE]

for future reference:

stock ecu:

Remapped ecu. see the difference?