Asteris said:
So you reckon you can make an existing SPI loom work with an MPI chip in a 1108 ECU? sounds fun, but wouldnt it be better using the 1242 ECU with your chip? I'm really interested in this
General 1/3 of the way there?
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General 1/3 of the way there?
So you reckon you can make an existing SPI loom work with an MPI chip in a 1108 ECU? sounds fun, but wouldnt it be better using the 1242 ECU with your chip? I'm really interested in this
Asteris
Member
punto_jr_sx75 said:So you reckon you can make an existing SPI loom work with an MPI chip in a 1108 ECU? sounds fun, but wouldnt it be better using the 1242 ECU with your chip? I'm really interested in this
The looms are the same. This is already confirmed, one of our members runs a 1242mpi engine on the stock loom for the past 6 months. Pin 18 from the ECU ends to the single injector on the SPI 55/60ps and in parallel to the 4 injectors on the 75ps mpi. So, if you fit the 1242 mpi engine, you just have to change the last part of the cable in order to connect the 4 injectors in parallel. Much more easy than changing the whole loom (which in fact is 100% the same for the rest of it).
See the schemes
60 spi loom
http://www.puntoclub.gr/files/punto60.gif
75 mpi loom
http://www.puntoclub.gr/files/punto75.gif
Greek descriptions, but it's easy to see the injectors to the right, connected to pin 18 at both schemes.
With the above setup, the only other thing you have to do is plug an 1242mpi ECU and drive away. This must be a year 94-95 unlocked ECU, in order to avoid immobilizer code problems.
What i am going to do, is to make a custom chip for the stock ECU, which will contain the injection and ingition maps of the 1242mpi chip. i believe it's a fairly easy job for a tuning shop, and this will also keep our immo working. Plus, i can make multiple copies of this chip (i have an eprom copier) and share the expenses with rest of my club members who did (or will do) the same engine upgrade.
Asteris said:
That is awesome work, well done
I have a mate just completed a 1242 cinq conversion and were going to go the full way and change the loom for an mpi ( had falsely heard hey were different), but instead opted for a 75 block (stronger than a 60) with a 60 head, 75 cam shaft with a 40mm throttle body etc, this might be an option for the future....
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Does the fuel pump have to be upgraded at all?
David
David
Asteris
Member
The right way is to change it for a Punto75 or GT one, as the spi one would probably fail to deliver the 3 bar pressure the mpi system requests, but we have a couple of guys that still work with the stock 1108 fuel pump, as it manages to push just fine the needed pressure. Mayby depends on their age. Try and see.
scottc1088
Member
do you know when this chip will be available?
ill be doing a 1242 conversion in the summer so after reading this ill most probably go for the punto 75 engine
are all the fuel lines ok for the uprated fuel pump?
ill be doing a 1242 conversion in the summer so after reading this ill most probably go for the punto 75 engine
are all the fuel lines ok for the uprated fuel pump?
scottc1088 said:
IIRC youre a mechanic, you tell us!!
Yes, theyve been proven as fine, but according to 'Oldschool', they need upgrading.
But yes, the SPi fuel pump tops out at 1.1 BAR and so an MPi pump would be needed
scottc1088
Member
i may be a mechanic but not a fiat expertarseofbox said:
they should be ok anyway as there rated at more than 3 bar
scottc1088 said:i may be a mechanic but not a fiat expert
they should be ok anyway as there rated at more than 3 bar
Isnt a fuel line a fuel line regardless of the car its it? Just because its Italian doesnt mean it conveys potatoes from the tank to the engine!!
scottc1088
Member
ok then
Asteris
Member
This chip will probably be ready within February. I'll let you know.
Fuel lines are ok. They are the same as the ones at the Sei MK2, which is an MPI and runs at 3bar. I have a very small doubt about the fuel filter fitted at spi's and removed at mpi Sei Mk2...
Spi pump tops at 1.1 bar due to the regulator that stricts it there. Mpi regulator is at 2.3 bar idle and 3 bar at full throttle. The spi pump can cope with that pressures, but probably can't handle for long the combination of high pressure and high supply asked at full throttle. Might work ok at low-mid revs and starve the engine at 5000+. As i said before a couple of our guys run fine without changing the stock pump.
Fuel lines are ok. They are the same as the ones at the Sei MK2, which is an MPI and runs at 3bar. I have a very small doubt about the fuel filter fitted at spi's and removed at mpi Sei Mk2...
Spi pump tops at 1.1 bar due to the regulator that stricts it there. Mpi regulator is at 2.3 bar idle and 3 bar at full throttle. The spi pump can cope with that pressures, but probably can't handle for long the combination of high pressure and high supply asked at full throttle. Might work ok at low-mid revs and starve the engine at 5000+. As i said before a couple of our guys run fine without changing the stock pump.
Asteris said:
Porting the 60 and the 75 head result in the same maximum port size.
You can use the chip of the 75 ECU anyway in the Cinquecento ECU. But once you have done this much head work it really needs a re-map.
Asteris said:
The valves are bigger too.
Asteris said:
If you keep the fuel pump from the SPI and you increase power delivery by several modifications you will run into dangerously long duty cycles that can kill ther injectors.
Asteris said:
If you do a chip, do it properly including any modifications.
Oldschool said:
Does that mean he would have to take into consideration the range of differently set up engines which this chip woud be used, as in, one chip for a highly modified engine down to just a practically bog-standard 75 MPI engine into a seicento/cinquecento?
Would it be possible to drop a Punto 75 MPI engine into a Sei Mk2 that is already setup for MPI injection?
If a 75 MPI engine was dropped into a cinq with a chip from Asteris that allowed use with immo and an uprated fuel pump was added, would it be possible to still add a turbo? If so what fuel setup would be need? Would a custom remap be needed of the ECU?
Thanks
David
If a 75 MPI engine was dropped into a cinq with a chip from Asteris that allowed use with immo and an uprated fuel pump was added, would it be possible to still add a turbo? If so what fuel setup would be need? Would a custom remap be needed of the ECU?
Thanks
David
you would need a custom ECU. As far as i know, even a remapped ECU will not be able to cope with positive pressure in the inlet. It'd mean everytime it came on boost, the ECU wouldn't know how to fuel it.
punto_jr_sx75 said:
Yes, and this is the reason why we are messing about with it to this extent on developping maps. A lot of the maps do work with a variety of engine modifications, but you are running the risk to do either damage the injectors when the fueling is not adapted to the demands or if the map is not up to it that the engine leans out dangerously under a variety of ambient conditions resulting in engine damage. Apart from it you will never reach the maximum power and torque output.
As an example we have done one 1242 16v engine done some modifications (not heavily modified) used the uprated re-map for the standard engine and got with the re-map done specifically for the car another 8lbf ft more torque and about 4bhp more pek power.
