Having run my st165 today at SRR i came away wiuth less BHP than expected and a lean running car!?

since the car was mapped back in 2009? i have adjusted the TPS into spec re st205 spec, assumed the PFC is looking for this spec to work as its a Plug and Play ecu?
also the car comes on and off Idle correctly as it should now.
I have also got a better voltage at the ecu and systems since it was mapped, all be it not a huge amount more.

Im left with the car running into the 13's for AFR....My question is could me adjusting the TPS have caused this, im thinking the answer is YES..

375 BHP before adjustment
346 After adjustment

Graphs can be found in the link below.
It looks like the whole fuel table has shifted?

http://www.flickr.com/photos/69betsy69/ ... 007787619/

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Steve Gillies
ST-165 88 UK

www.GT4-Play.co.uk

If you mean that you have changed the TPS angular zero point reference then I can imagine this would potentially offset the fuel map Steve. I'm sure others will be along soon with additional comment!

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Don
GT4DC Chairman
1994 Toyota Celica GT-Four ST205WRC JDM 269bhp @ 0.9bar
1994 Toyota Celica GT-Four Special GT 590bhp @ 1.8bar
1989 Van Diemen RF88/89 Formula Ford 1600
2008 Nissan Patrol GU 3.0L ZD30DDTi 154bhp

More likely is changing the voltage at the ecu as it applies dead time correction for the injectors. Higher voltage makes the injectors open quicker so the ecu shortens the injector pulse.
normally tps is only used for 'acceration enrichment' not for steady state fueling.

this highlights the need for wideband afr gauges in modified cars. Afrs in the 13s are likely engine killers.

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If at first you don't suck seed, try drier grain.

Hi Don, it's the only thing I can think of?
Charlie said it was the Fuel pump but I disagree with that.
In my experience of fuel curves and failing fuel pumps or FPR is the AFR graph is a bit like a banana in as much as the AFR dives down when the boost comes on but then starts to go back up as the fuel pump can not keep up with demand, or another part of the fuel system.
My AFR graph flat lines and actually goes a little richer right at the end.
This can also be seen in the AFR graph back in 2009?

_________________
Steve Gillies
ST-165 88 UK

www.GT4-Play.co.uk

Hi Chris, It's something I'm looking into purchasing, any one have any good or bad experiences with Wide band set-ups?

Ryan has an Excel program which I believe he can use to shift fuel maps by imputing your data and it carries out a calculation and spits out the new data to be input.
Any one know of such a set-up?

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Steve Gillies
ST-165 88 UK

www.GT4-Play.co.uk

Possibly a slight leak in the vac line to the turbo pressure sensor as it gets a little richer as more boost is applied

I've had experience of Zeitronix wideband kit - seems OK and accurate. I had mine (zt-1) permanentlyinstalled with the Zeitronic LCD display wired up the to the PFC via datalogit so that I could log everything via a laptop when I was mapping mine. It was pretty simple apart from the non linear output of the sensor which required an equation to be fed into the datalogit software - later zt-2 models have a linear output removing this I believe

I also have some Xcel spreadsheets for correcting fuelling based on logged AFR and current map - I will try to find them this evening

Innovate O2 monitoring kit also seems to have a good rep.

Do you by chance have maps saved from the good fuelling period? There are a few things in mapping that could cause this phenomenon - the PFC does have a TPS fuelling correction but there's a stack of others with injector size compensation being the one that jumps to mind - it's also the way to a quick fix too

I do indeed have the maps saved from the data Logit.
Of course I'm still running the same map as 2009
If you have the xcel program that would be awesome!

_________________
Steve Gillies
ST-165 88 UK

www.GT4-Play.co.uk

Did no one spot this






It could also be that climate conditions have changed and the other correction figures such as IAT aren't quite correct. This is why Toyota leave a large safety margin.

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If at first you don't suck seed, try drier grain.

I did Chris


Would make sense but only if the dead time numbers were set wrong

I think I'd also expect the Afr to look different - more of a general slope as dead time vs on time ratio decreases. There is some evidence of this so it's a very plausible idea

So the plan is to purchase Wideband AFR gauge, do some runs on the road, then remove the secondary battery cable and see if the AFR changes!
The power FC does have inj Vs voltage setting.


Sent from my iPad using Tapatalk

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Steve Gillies
ST-165 88 UK

www.GT4-Play.co.uk

It would be interesting to know the outcome. I had assumed you had beefed up wiring to the ECU only rather than the injectors as well.

It's surprising how much difference a volt makes in mixture terms, especially at lighter throttles.

_________________
If at first you don't suck seed, try drier grain.

I added an extra bigger cable running from the battery's original location under the bonnet to the battery in the rear.

_________________
Steve Gillies
ST-165 88 UK

www.GT4-Play.co.uk

I've found the xls file but it's not really very friendly for public consumption.

It's a bit of a mix of rocket science and Xcel hacking and I must admit I'm struggling to remember what figures have to be stuck in which tables

It's made for logging so it uses a combination of logged values weighted with the number of recorded instances, all compared to the inj and desired AFR to produce a correction and a new map suitable for hand finishing

I should be able to yank the calc bit out and make it simple but it'll be tomorrow

That's all good, thanks matey
I have purchased a wideband so will report back with my findings later in the week


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_________________
Steve Gillies
ST-165 88 UK

www.GT4-Play.co.uk

Sod it,

Maybe someone else can work it out

Also might prove useful when you get the wideband set up and do some logging

https://www.dropbox.com/s/cupe19cr1q7x0 ... 1_21xx.xls

This is using live data from my last session

Things that need to be filled in in the Calculations tab:-

Measured AFR table
Taken from FC log file :-
Open Map Watch
Open log file
Select AFR table
Select Average
Copy table and paste into Xcel

Samples
From above chart select samples
copy table and paste into Xcel

Target AFR
Taken from FC-Edit
Select Inj Map
Choose AF Ratio
Copy table and paste to Xcel

Current Basemap
Taken from FC-Edit
Select Base Map
Choose Base (mSec)
Copy table and paste into Xcel

Sample Threshold
Manually Entered
Determines the weight of the correction applied
Corretions based on measurements with samples < sample threshold will be scaled down
I used 10 so cells which only have one measurement make little difference but with 10+ samples I was applying the whole correction

Output

New Basemap
Corrected version of the basemap based on the AFR samples

Then copy new basemap table and paste special into "new fuelling map" table. Select Values

Switch to Graphical Comparisons tab
Look at the new fuelling map chart. You might well see that it's a bit peaky as in the example data. Smooth it by hand - lower peaks and raise points either side to achieve a smooth curve. Again look at the example data in the xls, Original Fuelling Map was previously hand smoothed by me


When you're happy switch back to the calculations page, copy the values from the "New fuelling map" table and paste into the Base map (Base msec) in FC-Edit


What I'm trying to achieve
Recalculate the base map so that the measured AFR closely matches the AFR table plotted in the INJ map. Once you've done that AFR changes are as simple as typing in the desired AFR in the INJ map in FC_Edit



I also have a spreadsheet for calculating IGN timing but that's really really complicated