BAD_MAN_121

Hi , whats this in my ecu, its like a board thats pined onto the original ecu,its a Z4 and is giving my car some extreme power,

i have a wrx sti v1, full decated and induction kit, its very powerful and my god has alot of torque, just keeps on pullin in every gear. 4th gear its doing 110mph, goin of the clock

Glowplug

iTrader: (8)

It is 'some sort' of Prova chip mate. The very early PolarPerformance looked similar to that.
Unless you can verify it's origin then what it is doing fueling wise is just guess work. Some one on here may be able to id it but don't hold your breath.

Best suggestion i can make, is to have the car on a rolling road and monitor/check the AFRs, timing and other variables etc.

edit: This thread may help, note Scott.T's replies in particular. Just use the search on here or google 'prova'.

BAD_MAN_121

Cheers mate, all ino that my sti pulls hard and goes like a roket, but due to the cold, it seems to be overboosting, you wouldnt have a idea on what boost they should be running do you .

dj219957

yes its a prova chip. i would take it out. they have a reutation to run stupid amounts of boost and ignition advance. they normally need at least 100 run fuel or higher (like they have in japan now).
do a search and you will see.
it can be taken if you prise it out and reconnect the j1 resistor. then you will be left with a standard z4 ecu which will run perfect in your car on 97 ron fuel.

Glowplug

iTrader: (8)

Your MAP sensor will govern the max boost you can run, iirc 1.27bar (18.4psi) is cut.
Educated guess i would say it is set 1.1bar. So only just under the cut limit, add the cold dense air and 0.17bar is easily achievable, hence you hit cut. But as i said, it's all guess work atm and that is no good to you at all.

As DJ says, until you can verify the map on the board, the best option would be to re-bridge the J1 joint (no need to remove the Prova board, as some times they can be soldered in place) and run on a standard OE Z4 map.

BAD_MAN_121

Cheers Guys, but i think ima leave it the way it is, i drive gently, and if a plan on racing away, gona put OB and optimax to increase the octane, which OB is good, people tellin me about STP.

Glowplug

iTrader: (8)

The 'only' OB i would use NF Here


Contradiction in posts there me thinks.

You do as you please, but be prepared to be flamed when you post "Help, It Has Gone Pop" or "I've Melted No.3 Piston".
For the sake of £50 (3 bottles of NF) and an hour on the RR, is it really worth the risk??????

Another option for you is to fit a switch to the ECU. This will allow you to run the 'safe' Z4 map until you get the Prova identified then switch between the two if/when it is safe to do so.

But like i said, you do as you please.

BAD_MAN_121

Would i loose the performance i curently have if fuel is set to uk octance instead of jap,

also whos the best person to get my car checked by, im from north west lancashire side.

BAD_MAN_121

but then again bearing in mind, its been in the UK since 2003 and still runing the same engine with no rebuild etc,

mickywrx

iTrader: (29)

http://www.tegsport.co.uk/ should be near you.

Glowplug

iTrader: (8)

No, i don't think so. It will just enable you to run UK fuel. It will still come on song when using V-Power or NF and will not DET it self to death when running lower octane.

You have no idea though, when that Prova ECU was fitted. I have 3 ECU's, a U8 and a Z4 both standard and a Z5 chipped. I could sell my car tomorrow with any one of them fitted.

BAD_MAN_121

yh true say, well ima take your advice and get it on a rolling road, Cheers mate