Jamesemt

Can I have two switchable maps?

I'm thinking one for economy and one for power??

OR

Could the car be mapped to pass emissions while being fully decatted as the second non-performance map?

Andy.F

Yes on MY01 onwards but the power/economy thing doesn't really work out, you can run at two different power outputs/boost levels but the ideal air/fuel ratio will be present in each case.

As far as passing an MOT cat test without a cat, then no you can't. Throughout the cat test the engine works in closed loop fuel control in both cases. Bottom line is you need a cat to pass a cat test ! (not a big one though )

Andy

Jamesemt

While you're online Andy can I ask what is a realistic power figure for a blob eye WRX and around £2k...supposing I bought most parts second hand...
Is it worth going over 280bhp?

Sorry, know you get asked this loads...car has a blitz back box and middle decat at present.

Many Thanks

James

Andy.F

There is another similar thread running at the moment on this topic although it has focused mainly on the Sti.
On the WRX I'd go for

Sti intercooler £250 (then sell yours to a MY93-96 owner)
Sti injectors £ 200 ?
Fuel pump £100
TD05 FE or VF34 £600
Decat downpipe £150 (keep your OE midsection for MOTs )
Ecutek remap £650 ish

£1950

Assuming here you can fit the parts yourself ? Turbo and decat new (cheaper s/h)
That should see you the right side of 320 bhp without putting you in the clutch/gearbox danger zone !

Andy

GaryCat

I have the switchable map on a 03WRX with prodrive backbox, de-cat centre and Sti air filter. On 'performance' map I get 264bhp & 264 lbs/ft torque. On 'economy' I get 31mpg averaging 80-90 on the motorway.

According to Power Engineering you should be able to get 280ish with a decat downpipe, for more than that you need fuel pump etc as Andy F says.

Jamesemt

320bhp sounds very tempting!!!

Bob Rawle

Economy is implicit in off boost driving, there should be no difference in that area whatever power level you set for any given mod state. Mapping upto and including the onset of open loop fueling and timing should maximise economy, beyond that its dependant on the mod state of the car and your right foot.

cheers, and happy new year

bob

Turbo_Steve

.....the right foot being the problem?

GaryCat

As i understand it, the economy map limits the amount of boost to about .7 bar (the perfomance map is about 1.1 bar), so when you do floor it in econ mode it uses less boost and therefore less fuel.

As Bob says, it only affects driving on boost but with most motorway driving, especially on the M25 it involves a lot of stop-start stuff so you do tend to floor it from time to time.

Aztec Performance Ltd

iTrader: (234)

Andy: what do you think of mapping to different boost settings using a MBC, to enable the user to increase/decrease the boost?

Bob

Andy.F

Yes, not a problem as long as the car has been mapped at both levels. Most aftermarket ECU's and boost controllers also give you this option.

Andy

Aztec Performance Ltd

iTrader: (234)

Using Tek?

Andy.F

Yes and no ! With a MBC you can't control the boost profile like you can within the ECU so your high boost map on the MBC may be limited by the boost the engine is comfortable with at the top end, therefore you could be missing out on midrange torque.
You could just 'T' in a valve to put the full air signal to the wastegate for low boost, or a switch in the car to cut the power to the boost solenoid valve which would have the same effect. If you used the switch idea then you would need a small resistor across it to eliminate the CEL thrown when in the low boost position.

Andy

DPat

So how do you switch between profiles then???

GaryCat

Press the throttle down fully and switch the rear-window demister on at the same time.

DPat

Thanks, while driving or just with the ignition on?

DPat

GaryCat

Either.