I have finally got my hands on a ScoobyECU, well 2 actually (long story ).

Simple question (I hope), do I fit one to my W6 ECU or the Z4 that I purchased a few months ago. I've done a search, but there appear to have been conflicting views about a year ago as to whether it makes a difference

 

It does'nt make any difference what ECU it goes in as its altering the map to its own anyway.

I had mine in a Z4 ECU so if you were still worried i would pick that one out of the two because then if you take it out its better as standard.

 

just to confirm, it makes no difference. as soon as u cut/remove the j1 connector on the main board it then reads the scoobyecu.

u would be better off fitting it to the w6 and selling on the z4 to someone who isn't as fortunate to get there hands on a scoobyecu.

cheers

 

jdm wrx is right. Should get 150 quid for the z4

 

It no longer matters, I succeeded in smashing a tiny component off the W6 whilst trying to get two pain in the **** screws out At least the screws in the Z4 came out easy enough

 

Z4 is slightly better anyway. It is less likley to suffer from fuel-cut at the top limit.
I think the discrete components on a Z4 changed slightly making it a bit more tolerant.

 

but fuel cut point is determined by the chip.

 

Yes, but IIRC the way the Z4 decides to fuel cut is a bit more tolerent

 

Socket was soldered in yesterday and chip plugged into it

With the Z4 alone, the boost max'd at around 13 psi which is about right.

I let it run in for around 10 miles, occasionally giving a quick blast in various gears, but not getting the revs too high. Eventually just went for it and it max'd at just over 16 psi, again about right. No signs of fuel cut thankfully.

I think the chip was taken back to the base map before being sent to me, so I didnt bother re-setting the ECU. I thought it would need to learn anyway?

The drive is basically as it was, but with an extra kick I think this might be because the chip's map is based on the Z4?

Now for the rolling road

 

Correct....

Target set at 16.5psi in W6, U8, 2C ECU can cause quite regular fuel-cut. But the same chip/map is a Z4 is alot more tolerant.

 

Confused now. When I bought a 'VOS-chip' ages ago it had the fuel cut set at 18psi, so, out of the range of the normal boost (16psi).

My scoobyecu has the fuel cut moved to the limit of the MAP sensor, which in my case is about 22psi I think (face-lift MAP sensor).

So you see, I thought the fuel cut was set as part of the chip programming.

 

It is set in the Chip, but if it is set near to the limit of the standard Map sensor, then the voltage returned to the ECU seems to be interpreted better in a Z4 ECU.

I've always put this down to a tolerance issue with the map sensor circuit within the Z4 ECU being tighter the the earlier ECU.

 

Ah, that makes sense, thanks!

Definately worth getting the 'facelift' MAP sensor if replacing the old one then.

 

Yes, but the ECU map needs to be adjusted to compensate for the later map sensor i.e the change in scale between 2.5bar and 3bar sensors.

 

so is this why mine seems to suffer from fuel cut at high speed in fifth on motorway and if so what can i do about it.
thanks jason

 

I wondered why my mapper paid so much attention to the map sensor I had installed.