EFI conversion of S3
Discussion
This has sprouted from another thread.
As requested a few details on an MegaSquirt EFI install on a 1981 S3.
MegaSquirt is a DIY fuel injection controller which can be bought for about $120. It is tuned with a laptop using free tunig software called MegaTune.
The engine on my S3 is a 912 with only a few mods (slightly ported head, LC14 cams, tubular SS exhaust manifold etc)
I managed to get hold of a set of ZAP 45mm throttle bodies from a later Esprit and these are bolted to a NA inlet manifold which was modified to have the mounting holes repositioned.
311cc/min injectors are mounted in the top land area (not sure what these were originally intended for but where great for drilling out to 14mm for the injectors) of the inlet manifold together with vacuum points in each runner.
To get the inlet length correct I made up some inlet extensions from alloy tubing to get a length of 17" which is slightly longer than the OEM setup.
The fuel rails I made myself from 19mm billet alloy bar.
A swirl pot was added due to no baffling in the fuel tanks.
I had a Lambda sensor boss welded into the exhaust manifold to allow closed loop operation with a narrow band sensor and it will work with a wide band sensor also which really needed to get the tuning correct.
Ignition is taken care of with Ford EDIS module and coil pack mounted on the end of the cam towers above the bell housing. The EDIS module contols all coil firing operations using a 36-1 tooth trigger wheel mounted on the front crank pulley. All the EDIS module requires is an advance signal and is controlled by the MegaSquirt ECU.
The MegaSquirt I have got is from the V2.2 group buy a couple of years ago. It is currently running MS'n'EDIS code version 3.007 which controls both fueling and ignition. This gives 8x8 maps for fuel and spark control (may not seem like many but you would be surprised how well it works), hard and soft rev limiters, cooling fan control and low RPM multi spark capability.
With this lot the car performs much better than before, no hot starting problems, smooth idle, easy to adjust for emission tests and it is fully tunable when making engine mods using the free software.
Shortly I will be upgrading to MegaSquirt'n'Spark Extra which upgraded ECU firmware and tuning software. This will give 12x12 maps for both spark and fuel control, launch control plus a whole bunch of other stuff.
When I get around to putting some photos onto a hosting site I'll link in some pictures.
For more details on MegaSquirt goto
www.megasquirt.info/
and
www.msefi.com/index.php
Any other questions let me know or email me at s3esprit(at)freeuk.com if you can't wait for me to post the pictures.
Andy
1981 S3
As requested a few details on an MegaSquirt EFI install on a 1981 S3.
MegaSquirt is a DIY fuel injection controller which can be bought for about $120. It is tuned with a laptop using free tunig software called MegaTune.
The engine on my S3 is a 912 with only a few mods (slightly ported head, LC14 cams, tubular SS exhaust manifold etc)
I managed to get hold of a set of ZAP 45mm throttle bodies from a later Esprit and these are bolted to a NA inlet manifold which was modified to have the mounting holes repositioned.
311cc/min injectors are mounted in the top land area (not sure what these were originally intended for but where great for drilling out to 14mm for the injectors) of the inlet manifold together with vacuum points in each runner.
To get the inlet length correct I made up some inlet extensions from alloy tubing to get a length of 17" which is slightly longer than the OEM setup.
The fuel rails I made myself from 19mm billet alloy bar.
A swirl pot was added due to no baffling in the fuel tanks.
I had a Lambda sensor boss welded into the exhaust manifold to allow closed loop operation with a narrow band sensor and it will work with a wide band sensor also which really needed to get the tuning correct.
Ignition is taken care of with Ford EDIS module and coil pack mounted on the end of the cam towers above the bell housing. The EDIS module contols all coil firing operations using a 36-1 tooth trigger wheel mounted on the front crank pulley. All the EDIS module requires is an advance signal and is controlled by the MegaSquirt ECU.
The MegaSquirt I have got is from the V2.2 group buy a couple of years ago. It is currently running MS'n'EDIS code version 3.007 which controls both fueling and ignition. This gives 8x8 maps for fuel and spark control (may not seem like many but you would be surprised how well it works), hard and soft rev limiters, cooling fan control and low RPM multi spark capability.
With this lot the car performs much better than before, no hot starting problems, smooth idle, easy to adjust for emission tests and it is fully tunable when making engine mods using the free software.
Shortly I will be upgrading to MegaSquirt'n'Spark Extra which upgraded ECU firmware and tuning software. This will give 12x12 maps for both spark and fuel control, launch control plus a whole bunch of other stuff.
When I get around to putting some photos onto a hosting site I'll link in some pictures.
For more details on MegaSquirt goto
www.megasquirt.info/
and
www.msefi.com/index.php
Any other questions let me know or email me at s3esprit(at)freeuk.com if you can't wait for me to post the pictures.
Andy
1981 S3
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