I'm looking into a project to fit spi to a carbed car,

Ideally I would like to only run one fuel line, do all the spi cinquecento /Seicento have the fuel pressure regulator on the throttle body?

Also which years/models have the non immobiliser ECU?

The first question is 'why?'

If you are trying to do this with a Fiat ECU, you will need a return, you will need the cannister control (not neccessarily the cannister itself) and a lambda.

Very early Cinqs, pre 95, don't all have immobilisers.

D

It will not be going on a fiat, I was planning on fitting to an 850 reliant.

The 899 system seemed like the closest OEM ecu around with only one engine speed sensor to control fuel and spark timing.

There is someone on the reliant forum that had fitted a complete 899 engine and ECU so I know wiring wise I can make it work,

I would rather not have two fuel lines running up front though, do any of the spi Punto etc run without a return?

It's not the end of the world running two fuel lines, one would just be tidier.

With a pressure regulator you must have a return, needs to go somewhere.

I understand the concept of putting it in a different car, carb and dizzy would be way easier.

D

Getting hard to find good used su carbs for the reliant even harder to find the 1l fiesta carb that people fit as an upgrade which cause other problems like poor hot starting.

The after market dizzies are junk with the wrong advance curve and vacuum unit, good enough to get you running but a pain to get right.



I know there has to be a return for the fuel pressure, some cars have the regulator on the pump in the tank (I'm pretty sure later MPI punto's have that set up).

Was just wandering if the cinq or sei ever had a single line set up.

Also do you know the throttle body size for the 899, the inlet flang on the robin is 32mm

Prawny12009 said:

There is someone on the reliant forum that had fitted a complete 899 engine and ECU so I know wiring wise I can make it work,

Click to expand...

:wave:

My advice is definately going to be make a new loom. Replace the decades old Reliant crust with fresh new copper and integrate the Fiat engine loom into it, I now have 3 independant electrical systems and problems with the lot.

Fuel supply is an easy one. I have a pump and high pressure filter under the car below the drivers footwell. Outlet of filter goes to throttle body. The return goes back to a T-piece on the pump inlet creating a loop that just circulates fuel. The other end of the T goes to the original tank outlet. Any fuel difference between pump out and return is drawn from the tank. It's proven itself with hours of sustained 50-60 MPH cruising.

As it's gone all Italian and the electrics are playing up (every fault code under the sun) I'll likely have the throttle body off in the next few days so I can measure the diameter while its apart. I'd say it's going to be a close fit as they're pretty similar sized engines.

I opened my ECU and removed the immo myself as I didn't get the CODE unit, it's a 10 minute job if you know what to do.

My reliant is a 1998 model so even though it is decades old the wiring is going to probably be newer than the cinq donor.

Are you using the original tank without any swirl chamber?

Have you run the fuel low yet to see if there is any fuel starvation on long right hand turns (roundabouts etc)

Prawny12009 said:

Getting hard to find good used su carbs for the reliant even harder to find the 1l fiesta carb that people fit as an upgrade which cause other problems like poor hot starting.

The after market dizzies are junk with the wrong advance curve and vacuum unit, good enough to get you running but a pain to get right.



I know there has to be a return for the fuel pressure, some cars have the regulator on the pump in the tank (I'm pretty sure later MPI punto's have that set up).

Was just wandering if the cinq or sei ever had a single line set up.

Also do you know the throttle body size for the 899, the inlet flang on the robin is 32mm

Click to expand...

Gotcha, I thought you were putting the Fiat engine in, not just the induction and ignition.

899 and 1108 TBs are 30mm. 1242 is a 32, 40mm is available from specialists on here.

D

Would the 1242 spi throttle body be compatible electrically with the 899 loom/ECU?

Some brands deliberately change plug shapes to stop plug and play upgrades between models.

Prawny12009 said:

Would the 1242 spi throttle body be compatible electrically with the 899 loom/ECU?

Some brands deliberately change plug shapes to stop plug and play upgrades between models.

Click to expand...

This time you are lucky. Straight swap.

D

Prawny12009 said:

My reliant is a 1998 model so even though it is decades old the wiring is going to probably be newer than the cinq donor.

Are you using the original tank without any swirl chamber?

Have you run the fuel low yet to see if there is any fuel starvation on long right hand turns (roundabouts etc)

Click to expand...

No swirl, stopped drawing fuel after about 10 minutes on an angle at KFC when tank was pretty much empty. Just going to use some high capacity inline fuel filters to act as a surge and not let it run too low on fuel.

Rewiring the car would be a good idea as it's a simple loom to make and there's wires running across the engine bay at the moment. Integrating it all into one harness will make working on it so much easier. You could always just run new wiring alongside the existing loom and tape/tie them in.

I'm considering going to CAN BUS to reduce the ratsnest of wiring beind the dash to 4 wires and a single connector.