john banks

Jim, I agree with Paul - fuelling on full load is open loop - no feedback system. Once your bigger turbo goes on and we map it, it will help get the most out of your injectors, the fuelling will be consistent and the throttle response better.

[Edited by john banks - 9/2/2002 11:09:48 AM]

P20SPD

iTrader: (1)

Bob to put that in lieghmans terms, does closed loop mean when you lift off the accelerator? Because i would say mine is much smoother when you lift off. Would this explain it.

PS can you mail me to confirm the 19th October is booked, and need some details of good hotels to stay for the weekend, cause me and wifey will make a weekend of it. Watch out swindon here i come.

[Edited by P20SPD - 9/3/2002 9:03:27 PM]

JIM THEO

Hi
Yesterday I installed my new Walbro 255 HP fuel pump (from Mark Aigin) in my MY00 PPP Impreza(+downpipe+exhaust manifold).
Installation according to www.Scoobymods.com was easy and took me about one hour.
I kept all the original parts as the two pumps were the same in size/shape/design and changed only the pump, although I had to slightly bend the main tube that leads to the pump as the new pump has opposite the two connectors on the top side.
Strange is that I have EXACTLY the same injector duty cycles as before at the same rpms. You can't see any difference between the two Delta Dash log files.
Is this normal?
Currently I am running 1,1 bar.
JIM

PS:No worries about any extra noise with the Walbro pump...same noise as before.

Pavlo

Are you measuring the O2 sensor?

The ecu wouldn't change the duty cycles, as they are set by the mapping. You might find though that you are running richer on the sensor at max power, as the old pump might not have been flowing as much.

Paul

dowser

As mentioned, fuelling is open loop on boost - so duty will stay the same. It's just that the engine will be getting the fuel it's suppossed to.

I didn't notice any difference on my car - remember, this is a safety mod, not a power one

Richard

JIM THEO

:wink: :wink: :wink:
Thanks

EvilBevel

Jim, when we fitted the pump we did see massive differences... Before, we were adding more & more fuel at top RPM/load to the standard ECU trying to compensate for the VF23. After fitting the pump we had to lean out most parts of the map there, leaner than the JECS would normally fuel. So it is still a very wise mod if you plan to replace the standard turbo.

JIM THEO

THANKS ALL

Bob Rawle

You will/should see some difference in afr's (oxy sensor output) but ... the duty cycle will stay the same as the injectors are still being opened and closed for the same length of time by the map settings. the only place it will vary will be when on closed loop.

Bob

Bob Rawle

Closed loop is "normally" below about minus 100mm of mercury vacuum. thats where the afr correction limit is set although a UK spec car (not P1) can be set to stop a bit higher than that. Once on closed loop the ecu attempts to control fueling to stoich by using the oxy sensor as a reference, with the uprated pump the duty cycles necessary for this will naturally be lower, the rest of the map is fixed though and, aprt from any compensation effects will not change the duty cycle.

Yes I can certainly confirm that you are booked for the 19th ... looking forward to meeting up. Will mail the necessary details.

P20SPD

iTrader: (1)

Cheers Bob, by "making a weekend of it" that was my way of telling her how much i have to pay you for the ecu etc.

Just got to figure out how to tell her about the FMIC and Turbo, oh and the AVOS that arrived yesterday.

P20SPD

iTrader: (1)

One final thing Bob, Link or "TEK3". Please see new thread as i dont want to disrupt this one.

Cheers

Steven

Claudius

P20SPD

Sounds like you're getting a proper ECU then? What is it?

P20SPD

iTrader: (1)

Dont know yet!!