Friday 16 August 2013

ECU re-mapping

ECU re-mapping

The J15 I have just built uses a Puma 1.7 vvti engine designed by Yamaha. I stuck with the Ford ecu to keep costs down and hoped to inherit the reliability of the original ford package. I have however uprated the engine with cams, Racing Puma plenum, ported the head and fitted a lightened flywheel with a racing clutch.

A chap called Nik from Sitec did the mechanical work a year and a half ago. He still worked at Sitec when I took the engine back to have the ecu remapped. He handed the rolling road work to Ross and we started to make enquiries at a company called PumaSpeed about uprating the ecu to a racing puma spec. It turns out there is a limited amount you can do to the Ford ecu's as they only allow you into an ram update area but you can however change a number of key things to improve the torque at low revs which is the inherent problem with the standard package. We changed the timing, fuelling and disabled the torque limiter.

The problem with the DUDE ecu that came with the original donor car was that no one could uprate it to the desired Racing Puma spec. That is because it was an early ecu from 1997 and could not be uprated to a racing puma spec. It does not appear to have the update area.

My understanding is Ford only ever kept one ecu for the ford Puma range and when the electronics package was uprated the ecu was backwards compatible with older harnesses/engines. If you asked ford for a new ecu for an older engine Ford then re-flashed the ecu to match the engine spec.

I managed to obtain a newer ecu from a 2001 car which had an identical spec to my original donor car. It came complete with a lock barrel and key.

There is someone on ebay currently publishing a  cross reference from Coded ECU to Ford
part No:
97FB-12A850-HB (DUDE) My original Puma 1997
97FB-12A650-TA (PEST)

97BP-12A650-KA(????)

98FB-12A650-HC (MUFF)

XS6F-12A650-AHB (TAPE)

XS6F-12A650-APA (TEAT)

1S6F-12A650-HA (DIVE) The 2001  I obtained from ebay

It turns out that about the year 2000 they went from a single Oxygen sensor to  dual sensors (one before and after the cat). This was a mandatory EU change to put on a light if the cat efficiency dropped be low an acceptable level. Puma speed informed me despite that change it would work with my harness.

My original DUDE ecu from Puma R873 CGB extract from Ford ETIS
29.08.1997
Vehicle Line:   Puma 1997-2001
Body Style:   3 Door Coupe
Engine:   Zetec 1.7 EFI
Transmission:   5 Speed Manual Transaxle - B5/IB5
Drive:   RHD FWD
Axle Ratio:   3.82
Emission:   EEC 96 Car (EEC 1)
Air Conditioning:   Manual Air Conditioning
Territory:   (+)"GB"
Paint:   Panther Black (Metallic)
Interior Colour:   Alchemy Interior
Interior Fabric:   Silverstone/Echo


The markings on the side of the DIVE ECU from ebay:

Reg X774 OAC extract from Ford ETIS

10.01.2001
Vehicle Line:   Puma 1997-2001
Body Style:   3 Door Coupe
Version:   Series 10
Engine:   Zetec 1.7 EFI
Transmission:   5 Speed Manual Transaxle - B5/IB5
Drive:   RHD FWD
Axle Ratio:   3.82
Emission:   2000 EEC (EEC 7)
Air Conditioning:   Manual Air Conditioning
Territory:   (+)"GB"
Paint:   Panther Black (Metallic)
Interior Colour:   Medium Dark Graphite
Interior Fabric:   Chrome/Twill
The trick is when you obtain an ecu from ebay it is advisable to get a key and lock barrel to match. This is to get PATS system to recognise the new key while keeping the steering lock functional. Failure to do this takes you into uncharted territory as far as I can understand.

The resulting engine power was about +17bhp from the original ECU but although the torque at lower speeds was improved immensely the overall power was a bit disappointing at 112bhp. There is obviously something wrong I will publish the final torque curve when I figure out what is wrong.


Original plot with DIVE

Ross

Nick and Ross after tuning

Contents


http://sylvabuild.blogspot.co.uk/2012/01/sylva-j15-is-kit-car-designed-by-jeremy.html

6 comments:

  1. Hi, Paul here fellow j15 builder. Just reading your latest blog. Is the published bhp plot the latest or is it old?. I can't work out why the bhp would be so low with that spec engine.....is the VCT system working?. Also the curve seems very lumpy, did they give you a reason for this....interested as I'm also running the puma engine, although I gave up with the ecu from the puma, and have decided to go emerald.....p.s. I still have the puma ecu (from a 2001 car) but not the key and immob sender....any use?.

    Paul.

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  2. The plot was where we started from before re-flashing the ecu. I took the car on a test drive after they worked their magic and was so excited by the performance I forgot to pick up the torque/bhp curves for that mapping. I am not sure if I can get the plot now as the two chaps in the picture have left the tuning company. I will try of course. I had the thing on a run at the weekend to Oban 226 miles and the fuel consumption was 47/gal. The performance was very good considering I was two up. The performance is not blistering compared to my Westfield SEIW Duratec but the road holding is so much better I recon it will give a good account of itself on the track.

    There is nothing wrong with the ecu to change ecu's without hastle you need the barrel and key otherwise they are just a lump of glass.

    According to PumaSpeed the torque curve on that engine/ecu is normal. You can help the torque curve by removing the torque limiter on 1st and second gear (which has been done). I have also had the timing and fuelling changed to improve that part of the curve. The test run to Oban would confirm a much more drivable car with improved low speed torque (2-3K revs).

    If I want more performance as you say I would have to adopt throttle bodies which I am not going to do.

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  3. Great stuff, and glad you are saying the handling is good...I'm hoping to be on the road next summer but we will see....would love to see a few pics of your exhaust system if possible?

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  4. Hi,
    I have only two pictures on my blog:

    http://sylvabuild.blogspot.co.uk/2012/04/trial-engine-fit.html

    http://sylvabuild.blogspot.co.uk/2013/03/mirrors-exhaust-and-wheels.html

    The index is always here:

    http://sylvabuild.blogspot.co.uk/2012/01/sylva-j15-is-kit-car-designed-by-jeremy.html

    I am always pleased to take more pics of course (as I am pleased with the build). The exhaust manifold was supplied by Jeremy, I had a few issues with that as the engine flange was not flat and leaked. I spent an hour or so on a belt sander and added a thicker gasket. The exhaust can is s/h from a Westfield and has a built in CAT. I got a chap to mate the exhaust can to the manifold (and what a neat job he did). This allowed me to run the engine at an early stage. I could not get the same chap to do the tail section so I fab'd it myself (a much less tricky job). The tail section is removable so I can fully rotate the rear tub for major maintenance activities. If you want more pics etc mail me directly on oddjoblinlithgow@gmail.com any time!

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  5. Return to Sitec (tuners) yesterday confirms my throttle is not opening far enough (about 20bhp short). Initial investigations look like it is not immediately simple to increase the range of opening. My first thoughts are to modify the throttle cam on the throttle body. Look for next update to blog and hopefully new power curves.

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  6. Just FYI, I had an issue with the throttle on my westfield. I'm sure you have considered this, but moving the attachment point on the pedal can give it a longer / throw (thus uses more cable). Anyway, possibly the easiest 20bhp you will get :-)

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