unichip learning... does it really?

[unfamilia]

talked to a guy who is a senior tech at aps at another clubs meet up on sunday, when i told him i had a sportivo and was looking at a unichip but told himn about the ecus learning around them, he said shouldnt happen. It could (meaning might have a change of) happening with gen 1 unichips but not the latest ones....

he said if i want to go for one to tell him and if it learns its way around the unichip... he will do a deal for me.

[CHA54]

of course APS are going to tell you it wont learn around it... that way they have more chance of making a sale.

The extent the stock ECU will correct around the unichip depends on how much the tuner tries to get out of the unichip in terms of gains.

Timing advance is where the majority of gains are made in any highly strung NA setup when only modding the ECU maps. Too much timing and the engine will start to knock, when the engine knocks, the stock ECU will pull out ALL the timing advance to protect the motor. eg, stock ECU was aiming for 20deg advance and the tuner wanted 30, so tuner dialed in an additional 10deg via the unichip in the particular sections of the map, and this leaves the engine right on the limit of the knock sensor readings... You get fuel from another fuel station or the outside air temp changes, or you've got more weight in the car the next day, the additional timing induces extra knock to be picked up and the stock ECU pulls 20deg out of the map, so now you have 10deg instead of the 30 the tuner was aiming for.... LESS POWER!! :P

I've posted before about how you should try to borrow a snapon OBD2 scanner or the toyota scan tool, plug it in and go for a drive monitoring ignition advance and the knock readings. When you do this you can see how early the stock ECU starts to pick up knock (WAY before it's audible), then you can also see what the stock ECU does with regard to ignition advance when there is knock present...

The stock ECU is always adjusting to suit the fuel/temps/load/conditions, so if you have an interceptor in place trying to push the limits to get more power, you run the risk of the car working fine for a couple of days and then running worse than if you had no unichip at all.

When we tune marks emanage setup for the turbo, it's being done with an OBD2 scanner in place to ensure the knock readings are acceptable and the stock ECU isn't going to try and do anything stupid with the maps, it will be a conservative tune, but with a turbo he'll be making double the power than a stock car anyway.

[DANZZT231]

So is the turbo in yet or what man? :P

[CHA54]

it's getting closer, basically just the speedflow/earls stuff to source now.

[CAP]

So are we saying that if the tuner goes for a more conservative tune, you're less likely to get problems with the OEM ecu overriding the Piggyback settings?

[CHA54]

yes

[lucio_libre]

So it's not value for money then?

[CHA54]

depends on what it costs you, and what goals you want to achieve.

eg, secondhand emanage with DIY install and an hour of dyno tuning can be done for $500, then you can tweak it yourself if you need to, the thing with the unichip is you're stuck having to go back to a unichip dealer and paying their fees if you need a change. Ultimately a standalone ECU is the way to achieve consistent power, but depending on the ECU you also run more risk of grenading your motor as you usually dont have failsafes like knock control etc...