13 replies to this topic

[blackbelt1990]

Morning all,

Is it possible to swap a single plug ECU for a twin? I’ve got a single plug sidewalk engine in my current project but have got my hands on a twin plug cooper ECU and engine loom. Just wondering whether I can swap the two? If no one has tried then I might just have to have a go!

Cheers

[Dutchdave's25]

Its not just the wiring loom in the engine bay that's different,

the twin plug ecu needs an accelarator pedal switch, it will run poorly without it.

[blackbelt1990]

Its not just the wiring loom in the engine bay that's different,
the twin plug ecu needs an accelarator pedal switch, it will run poorly without it.

I didn’t know but... the sale included the body loom aswell! Haha

I’m just thinking it’s probably worth swapping as the Cooper ECU is claimed to be a better one? The car is currently stripped.

[cian]

The standard spi and cooper spi engines are different ( cam and compression ratio ) not sure if the ecu is different however

[Dutchdave's25]

I believe the Cooper ECU should give you about 10% more power (with the right setup), I think i read that on this forum.

 

The twin plug wiring for the body runs through the roof rather than over the floor. not a hard job to fit it, just fiddly

[blackbelt1990]

Cheers guys, I’m going to use the complete earlier loom and ECU and drop in an aftermarket cam. I might get the head skimmed a touch but not sure yet.

[Dutchdave's25]

Cheers guys, I’m going to use the complete earlier loom and ECU and drop in an aftermarket cam. I might get the head skimmed a touch but not sure yet.

 

Sounds good!

Berfore I forget, the throttle pedal itself is also different (because of the switch thats mounted to it)

[blackbelt1990]

Cheers guys, I’m going to use the complete earlier loom and ECU and drop in an aftermarket cam. I might get the head skimmed a touch but not sure yet.

Sounds good!
Berfore I forget, the throttle pedal itself is also different (because of the switch thats mounted to it)

Thanks! Out of interest, where is the switch on later SPIs?

[cian]

The switch is on early spi and it’s under or beside the pedal on a small bracket ( I can’t quite remember ) the switch was replaced with a more conventional throttle position sensor that is now expltremely difficult to source new

[blackbelt1990]

The switch is on early spi and it’s under or beside the pedal on a small bracket ( I can’t quite remember ) the switch was replaced with a more conventional throttle position sensor that is now expltremely difficult to source new

Cian, does that mean that the throttle body or inlet manifold is different on later cars?

[genpop]

 

The switch is on early spi and it’s under or beside the pedal on a small bracket ( I can’t quite remember ) the switch was replaced with a more conventional throttle position sensor that is now expltremely difficult to source new

Cian, does that mean that the throttle body or inlet manifold is different on later cars?

 

no,it is done within the software

[Bobbins]

Morning all,

Is it possible to swap a single plug ECU for a twin? I’ve got a single plug sidewalk engine in my current project but have got my hands on a twin plug cooper ECU and engine loom. Just wondering whether I can swap the two? If no one has tried then I might just have to have a go!

Cheers

Surely using an MPi ecu with single point injection would completely mess up the fuelling?

[blackbelt1990]

Morning all,

Is it possible to swap a single plug ECU for a twin? I’ve got a single plug sidewalk engine in my current project but have got my hands on a twin plug cooper ECU and engine loom. Just wondering whether I can swap the two? If no one has tried then I might just have to have a go!

Cheers

Surely using an MPi ecu with single point injection would completely mess up the fuelling?

Twin plug, rather than twin point lol. Earlier SPi cars had two ECU plugs, later cars had one.

[FlyingScot]

Cooper and standard ECUs different (different fuel maps) as well as internal components on cooper engines (no not inlet or throttle body) to give higher compression. If you have a UK spec sidewalk there is also the immobiliser to consider as it is probably matched to your current std ECU.

FS