Rev 5 N/A engine into Rev 2 N/A help

[jordanb7426]

Hi guys,

Just joined up for a bit of help with some work I'm doing for a friend (Jess on here)

She recently bought a Rev 2 MR2 with a knocking engine. After a look at it we discovered it had spun a shell so i told her it would be easier and cheaper to find a new engine to slot in.

The replacement engine she found locally was a Rev 5 engine. I wasn't sure it would work but and after a chat with the guy selling it (I think he's also on here and some other MR2 forums?) I was assured that with a non-immobilizer Rev 3 ECU which he agreed to put in with the sale and some pin changes it would work and that it would be a better lump in the long run than putting another Rev 2 engine in.

The engine went in nice and easily but now I've got to the wiring side of it to get it running. I'm struggling to find information on what has to be changed and where.

By the looks/sounds of it wires need to be changed in the white plug in the boot and the 22P plug on the ECU itself. Also possibly some bits to change in the loom behind the passenger side trim? I've also seen mentioned that it might need a Rev 3 ignition coil, is this needed ot is it just for converting to tubby?

any help would be appreciated

[madbasshunter]

Best person to ask is Peter http://www.imoc.co.uk/forums/profile.ph ... file&u=885
Think you need to use the rev3 engine loom and ecu and then make some changes in the fuse box, wiring to ecu and plug to body loom.

[tsango]

I sold a Rev 5 engine to someone with a REV 3 (or lower) and Peter helped them put it in.

I know there was some stuff about the ECU and immobilizer, and if you used the REV 5 ECU you'd have to have the Coil and key part (with chip in it).

I think the guy I sold it to used a REV 3 ECU though and it all worked ok.

As far as I know it wasn't straight forward though.

[madbasshunter]

Double post
please Delete

[Super_red]

I beleive there are differences in cam profile aswell so you may want to fit Rev 3 cams as the ECU will have the wrong map for REv 5 cams. This will then give you the full rev 3 power, 170+bhp so is a good thing over the 150ish of the rev 2 engine.

[bennn]

I beleive there are differences in cam profile aswell so you may want to fit Rev 3 cams as the ECU will have the wrong map for REv 5 cams. This will then give you the full rev 3 power, 170+bhp so is a good thing over the 150ish of the rev 2 engine.

I dont think there is, only difference between the Rev 3 engine and the Rev 4/5 Engine is the EGR Valve.