3 replies to this topic

[pugpg]

Hi guys, in new on this forum but joined because ive read so many interesting conversations in the SPI specific forum on peoples setups.

I have a bit of a query and was wondering if anyone can help me out....
Basically ive got a 1994 Spi Cooper, with single button alarm fob. But i want to experiment with different throttle bodies, injectors and ECU's but want to be able to go back to the standard setup which is currently working perfectly well. Ive bought a 91 Metro GTA ECU (which im told is interchangeable with the Mini SPi one) and am trying to source a Rover 1.4K16SPi injector from the 16 valve metro to go with a slightly larger throttle body.

But i understand that my alarm and fob will not work with this ECU? or is there a way of getting my original alarm and fob to work with the new ECU from the metro? (if so is it easily reversible?) This is quite important as i would like to keep my standard alarm and imobiliser because the fob also operates my remote central locking which i have recently fitted.

If i am fiddling around changing my ECU, will i be able to at any point put my old standard one back and it will WORK? i am hoping that this is possible and that changing the ECU then changing it back will not affect the alarm and imobiliser operation? This is also quite important as i would like to keep the alarm and imobiliser operational as i use the car everyday! which is why i am hoping i can easilly change it back without any problems.

If someone with more knowledge than me could help me that would be great!

[Sprocket]

Do the modifications on your engine justify the change to a Metro GTa ECU? Have you got the correct Metro GTa 16v SPi ECU?

If you have the correct ECU you can change the ECU without modification to any of the wiring. Your alarm will work as it should as it wasnt untill 1995 when the whole model range changed to SPi and Engine ECU/ Alarm ECU coding started.

The biggest question is, Does your engine justify the Metro GTa ECU. Has the compression ratio been rased above 10.5:1?

If no to both those questions, you will gain nothing by swapping the ECU

[pugpg]

The part number on the ECU is MNE 10012, its off a 1991 1.4 16Valve SPi Metro GTA. so as far as i know this is the right one?
So the alarm and immobiliser will work with any ECU in there? would this also mean that if i bought one of these newly developed German re-progamable ECU's the alarm and imobiliser would still work? this is another option, but i understand they are about 450 quid although you get the ability to program it yourself how you want which would be nice. Not sure how you actually buy them though, its not obvious on their website.

The engine modifications at present will not justify the new ECU, but as i ran into the ECU for £20 quid i bought that first. The car is currently still 1275cc with the K&N induction kit, Maniflow LCB manifold, standard cat and RC40 (i think!) DTM backbox. But next is the Mini Sport Stage 3 modified performance cylinder head, fully polished, ported and gas flowed, with 35mm larger inlet valves and increased compression ratio and Mini Sport 1.5:1 ratio alloy roller tipped rockers. I was then going to fit the Rover 1.4K16SPi injector from the 16 valve metro and a slightly larger throttle body.

Do you know what the compression ratio is raised to with this head? as im not sure. Do you not think there will be any difference / benfit using the Metro GTA ECU then? Before the Maniflow Manifold and K&N were fitted it was taken on the mobile rolling road at Gaydon last year where it was running at 59.5BHP.

[Sprocket]

Im not sure if that ECU will do what you want. The one I used has been tested and is known to work.

at 60bhp, there will be no benefit. Only when you get to 90bhp plus will it be of any use, as long as the compression ratio is high enough.

Most off the shelf modified heads will have a standard size combustion chamber, so they do not alter compression ratio.