Hello again all. Yesterday, i became the proud owner of a lovely 50k mile 1242 75 mpi engine. woo hoo. Anyway, my brother is fitting it for me as i'm a little cack handed with the spanners, and he's relishing the challenge of getting it to run on mpi. we had a bit of a discussion, and came up with some possible solutions for the problems outlined in the "sticky" on this subject.

Firstly, wiring. and i quote pete:

"you would need to have the Punto 75 ecu and engine bay wiring loom mated up to your cento - not too easy as the Punto ecu's sit on the opposite side of the engine bay."

How about mating it to a sei mpi loom? if not, why not mount the ecu the other side??


again i quote pete:


"The 75's ecu and injectors need to be supplied with between 2.5 and 3.5 bar of fuel pressure (depending on year of donor car) as opposed to the 1.0 bar that the Centos run at - something which you will need to address"

Will the 75's fuel pressure regulator not sort this problem?


any help, or other suggestions will be gratefully recieved, and thanks to pete for writing the original article in the first place, without that, i wouldn't even be doing the conversion. the cinq would probably be broken for parts by now.

Hi,
The punto/sei pressure regulator may allow the supply of the 2.5-3.5 bar but the pump and pipework may not be rated up to that kind of pressure, you could end up splitting a pipe or burning out/overheating the pump(not good as its surrounded by petrol) . Your best bet would be to take the full fuel system and ecu from a mpi sei and transfer it accross..

Thanks
Paul T

what are you coverting here - dropping an MPI 1242 into an SPI Sei of a Cinq? Is it worth the hassle? Just use the bottom of the new engine, and keep your old head and manifolds and source a Punto60 TB.

paul_treg said:

you could end up splitting a pipe or burning out/overheating the pump(not good as its surrounded by petrol) .

Click to expand...

Actually, and I know I'm being pikky here, but if the pump is completely surrounded by fuel there is no danger. It only becomes a problem when the tank is not full.

Cheers

D

rallycinq said:

Actually, and I know I'm being pikky here, but if the pump is completely surrounded by fuel there is no danger. It only becomes a problem when the tank is not full.

Cheers

D

Click to expand...

Hi,
Yeah I know needs air to burn, but just trying to put Fuct_it_up off the idea of using the standard fuel system at increased pressure, thinking of safety......Murphy's law, if it can go wrong, it will go wrong.....

Thanks
Paul T

arc said:

what are you coverting here - dropping an MPI 1242 into an SPI Sei of a Cinq?

Click to expand...

Yeah, 1242 mpi into cinq. really fancy giving mpi a go, so yes it is worth the hassle (too many 60 cinqs about these days).also don't see the point in sourcing a new tb when i have a perfectly good mpi one.

also, thanks for the pointers on the fuel pump, had not thought of that, i think getting sei pump and pipes is a good plan. I already have the punto 75 ecu, so don't need a sei one.

does the mpi punto have two lambda sensors? the mpi sei does - so the sei ECU will be expecting two readings.

I suppose if you have time and the tools then why not give it a bash, it wouldn't be the first MPI Cinq but one of a select few.

Good luck.

Liam

so wat extra will u get out of the MPI then? how much more horse power u talkin about?

and surly MPI means there are more things that can go wrong lmao

75BHp minimum...

could be fettled for plenty though (A mate had a VW Polo 1372cc MPi running 96BHp - at the wheels I think)

thanks again dudes. I think, seen as the engine came with all anciliares like loom, ecu, throttle body, etc, it would be a shame not to at least give it a go, and if it all goes tits up, then bung on a 60 tb and live with that.

Turns out, the mrs has booked us a week in new york in 2 weeks, so won't be able to start it for a while, boo hoo. who'd have thought a trip to new york would be less exciting than a new engine.