Ive just spent the day down at Star Performance on the rollers and have found some interesting ECU related facts...

The car is 93 WRX
Downpipe
Full Magnex
Induction Kit

First run was 261Bhp @ 6000rpm/ 240Lb/Ft

Subsequent runs made exactly 255Bhp but only 229Lb/Ft.

This was at 13PSI held.

Fitted a modified JUN ECU and the power immediately went to 270BHP @ 5500RPM and 253Lb/Ft.

However the boost was now up to 18PSI but fluctuating badly-2PSI either way.
Fitted a bleed valve to set the boost at 16PSI and found the power had dropped back to 220BHP.

We proved this new ECU (modded in Japan by JUN) is not suited to my car at all, the resultant power curve was dreadfully peaky. I would expect on the road it would be less enjoyable than standard.

Throughout the day we found the CO2 to be around 12%. Now this is hugely overfueling. No doubt with this fuel removed from the map, the car would naturally build power without the need to up boost.

Does anyone agree with this and is this really how badly the WRX overfuels?? If so, no wonder the fuel economy stinks

Hope they're are some good points here, please feel free to raise anything which you feel is relevant.

Finally, I cant speak highly enough of Jimmy at Star Performance in Glenrothes as no doubt many of you will agree who met him on Sunday. Time wasnt an issue and I felt very happy with entrusting my pride and joy

Cheers all

Richie

 

Hi Richie,

It sounds like the ECU is not mapable, you should bear in mind that a Jap ECU will probably be mapped for 100 / 104 RON fuel. When I bought my last car (93 WRX) it had a Mines ECU which I quickly got the dealer to replace. I now have a Unichip (from Powerstation) which I am more than pleased with , everyone says that all Scoobs are different when it comes to mapping so it makes sense to get one tailored to your car by someone who knows the engines inside out such as BRD or PS.

Cheers
Andy

 

RichieC,

I have a 92 WRX(must be one of the first), bearing in mind what you said about the first couple of runs with the standard ECU, my car seems to perform very differently from day to day and i put this down to how dense the air is. It certianly drops boost when driven hard for a while.

With regards to ECU swops, this is next on my list of mods ......any recomendations bearing in mind price is an issue!

cheers for any comments Daz

 

Andy,
These ECUs are mapped in Japan by JUN but for the UK market and our fuel. he imported a load of 97RON fuel to set them up and hence should have no probs. The ECU is not mappable, its a fit and forget unit.

Darren,
What sort of power is your WRX making? On a Rolling Road the barometric pressure and tempreature have nothing to do with the run as it is compensated for by the machine. Defaults are set and so it doesnt matter if its foggy and wet or clear and dry. Im looking into the whole Unichip idea as I want this extra fueling mapped out to get rid of the huge CO2 reading. Boost up a little but not a huge amount (not the 20PSI overboost I was seeing today, how lively was my sphincter) ??

Richie

 

Richie

I haventyet had the chance to put it on a rolling road as i dont think there are any 4 wheel drive versions near me.I was planning on a unichip conversion soon and getting it all set up then, this seems to be the favoured chip at the moment....have you any idea what it costs and what power i might expect?

Daz

 

Regarding your CO2 reading of 12%, that is exactly the same my MY00 was last there Sunday. Does anyone know what this is supposed to be?

I was looking at a ditial motors chip (swiss company, advertise in Evo (only for uk spec cars though)) I got them to e-mail me details in English:

-100% conform to "DOT CO" and "HC" emmissions polution requirements
-100 % reliable without default after test.
-100% Street legal
-5 years warranty, without km limit, (you vehicle will not loose his
manufacturer warranty

Performance difference:
+ 50 Bhp +25% (Nm) Torque, at -300 tr/min

I am just looking for a slight boost in power (50bhp looks somewhat optimistic), and peak torque moved lower down the rev range. Has anyone tried one of these?

 

The Unichip is £495 + VAT.

This includes fitting and setup from Powerstation in Cheltenham. There are some other approved fitters round the UK but not sure who.

Regards

Richie

 

Out of interest what sort of power and torque were you getting Robertio??

Ideally the CO2 should be between 7 & 9 %.
You could smell the overfuelling on mine it was stinking at full boost.

Is my Lambda sensor faulty or is this just how badly they overfuel??

Richie