what is actually done during a tune

V8XTasy · 23-05-2011, 10:14 AM

hi,

I'm thinking of taking my BA 5.4 V8 3v Falcon for a tune as I've put an aftermarket exhaust on it, but I'm confused as to what get tuned (I haven't had an engine tune on a modern engine with a PCM before). If they increase the fueling, doesn't the closed loop system detect a rich mixture and lean it out anyway? And if it's already too lean, wouldn't the system enrichen it? What other things do they do to increase performance?

Thanks

Grippy · 23-05-2011, 10:35 AM

Air Fuel ratios are tweaked, if auto shift points and harshness can be changed. Rev limits and points can be changed and different tunes for different fuels can also be modified and stored.

Tobey · 23-05-2011, 11:20 AM

They will also add more spark, change temperature settings (fans), idle control, the list goes on...

Best to pick a tuner then ask them all of the questions.

madmelon · 23-05-2011, 01:03 PM

Closed loop mode only occurs at low throttle positions. At high(er) TP, the system runs in open loop and this is where the performance tuning is done. Fuel can be changed to do whatever is requried here, along with other things.

V8XTasy · 23-05-2011, 01:26 PM

Quote:

Originally Posted by madmelon

Closed loop mode only occurs at low throttle positions. At high(er) TP, the system runs in open loop and this is where the performance tuning is done. Fuel can be changed to do whatever is requried here, along with other things.

Thanks, I just tried it with my OBD scanner and found that it does exactly that, I never realised that before. Time for a tune.

Bossxr8 · 23-05-2011, 04:02 PM

Quote:

Originally Posted by V8XTasy

hi,

I'm thinking of taking my BA 5.4 V8 3v Falcon for a tune as I've put an aftermarket exhaust on it, but I'm confused as to what get tuned (I haven't had an engine tune on a modern engine with a PCM before). If they increase the fueling, doesn't the closed loop system detect a rich mixture and lean it out anyway? And if it's already too lean, wouldn't the system enrichen it? What other things do they do to increase performance?

Thanks

A tune is more likely to lean the mixture a bit than richen it, as the factory tune is nearly always on the rich side to cool the cats and to allow for a bit of fuel pump degredation over time, among other things.

A tune changes the parameters the ECU uses to detect a rich or lean mixture, so if it went richer it would not lean it out because as the base parameters have been changed it will not adjust it as its already where the ECU tells it it has to be. Thats what a tune entails, changing the base parameters the ECU uses to adjust fuel and spark etc.

xtremerus · 23-05-2011, 05:45 PM

Does it need a tune for just an after-market exhaust??

xls3v · 23-05-2011, 06:40 PM

mine made 224rwkw after a tune, exhaust and airbox mods.. great mod picked up around 25kws from the tune

SteveJH · 23-05-2011, 07:19 PM

Quote:

Originally Posted by xtremerus

Does it need a tune for just an after-market exhaust??

Would depend on model I6, I6T or V8. In addition it depends on whether its a full exhaust or just catback.

Bossxr8 · 24-05-2011, 06:52 PM

Quote:

Originally Posted by xtremerus

Does it need a tune for just an after-market exhaust??

Not for a catback, maybe for a full system if its Euro 3 and it has post and pre cat oxygen sensors as changing the exhaust can bring on the engine check light.

lamborghinifan · 25-05-2011, 05:38 PM

i'm actually in the same boat here with a 3v and soon to be sports exhaust on it. also on injected gas. does it need a capa box or flash tune? don't really know what these things are exactly or how much is within the limits of the onboard control modules?

kinksta · 25-05-2011, 05:48 PM

Quote:

Originally Posted by xls3v

mine made 224rwkw after a tune, exhaust and airbox mods.. great mod picked up around 25kws from the tune

If I can ask, how much in total for 25kws?

V8XTasy · 25-05-2011, 09:31 PM

I had a quote from 1 place for $1500 for a dyno tune, seems a bit steep. What do you think?

Any suggestions for a good place to take it around West or North Melbourne? I know there was a thread on this previously, but it was a bit old and some places have closed down.

As well as the catback exhaust, I'm doing the intake mods; replacing the intake tube, F6 additional intake and K&N filter.

Phyber · 25-05-2011, 09:44 PM

Did that include an XCAL tune box as well?

Generally tunes seem to be $600-$1000 from most sponsors (my tuner XFT is $1000). If it's a B series or FG the XCAL3 box they use now is like $800RRP or something.