brickboy

I've been having a search around to see what combination of circumstances triggers the transient overboost on the TDCi motors.

Ford make a big play of this feature in all its tech specs, but so far I've only found fairly vague descriptions such as " it happens when full acceleration is required" or "under hard acceleration". Nothing technical, or more detailed about when it happens, and the circumstances.


Anyone know:

--> is it only triggered when the pedal is floored (similar to kickdown in an automatic)?

--> or is the ECU clever enough to give overboost if the pedal is 'stabbed' quickly, over a certain defined range of pedal travel?

--> is it only available in certain conditions (i.e. coolant / oil temp above a certain range, exhaust gas temp in a certain range etc)


I would have thought the driver has to actively initiate it with a determined right foot -- especially after the "unintended acceleration" lawsuit that hit Audi in the US in the 80s.

Any thoughts / input / links gratefully received.

cheers!

Shark Man

Basically, floor the acelerator pedal.

It runs higher boost pressure and injects more fuel for about 10seconds or so

Then ECU drops it back to "normal" boost thereafter, and usually won't let you do it again for a minute or so.

Can't remember the exact times, but I think coolant temp has to be at normal operating temp to work.


Just a gimmick; to temporarily increase the power output of an engine incapeable of producing more power for sustained periods without suffering from long term reliability issues (wear, excessive oil or exhaust or air/charge temperatures etc) and/or emissions issues (CO2, Particulates or NOXs).

brickboy

cheers Shark Man

Shark Man

Just had a thought. It wouldn't suprise me if it didn't work in 1st gear either. To reduce traction/torque steer issues and preserve the drivetrain.


I need to borrow my mates new focus and stick it on a dyno

brickboy

I have read on some of the Ford forums that torque is limited in 1st and 2nd.

Let me know if you do get the Focus dyno'd

J4CKO

iTrader: (1)

My Saab is limited in 1st, I like control of when and how 288 lbts ft is deployed, not nannying !

My missus has a 2.0 tdci Galaxy, sometimes that feels quicker than others, maybe its the overboosting feature I am noticing, it moves quite well for a big lump.

brickboy

Common feature of modern drive-by-wire turbodiesels I think, sometimes they feel quick and other times like they are towing a trailer

shep ppp

yep it only works in 3rd gears and above on the 2.2 diesels gives 400nm, which is nice on motorways/overtaking etc