M20B25 into M20B20 swap

[laurencecarter]

Hi I have a facelift 89 320 and have bought a 89 325 lump to swap into it. I know this is a simple swap and have a 173 ecu to use with it. I was just wondering if anyone knew any additional parts that need swapping. Is it really that simple?

Thanks Laurence

[HairyScreech]

It is really that simple.

How much of the donor engine have you got?

As the ideal is to put the whole lot in with gearbox, prop, diff and exhaust.

[laurencecarter]

I have the block and the box to go in. Have a fairly free flowing exhaust on there already. Will I need the afm from the b25?

Thanks

[Cloggy Saint]

You'll need the afm, inlet/injectors, throttle body. If you're using a 2.5 box you'll need a 2.5 prop shaft but it's ok to use the 2.0 box/shaft too.

[laurencecarter]

Would it run on the 2.0 afm, inlet and throttle body but just be restrictive? I will prob just use the 2.0 box

[Cloggy Saint]

If you use the 2.0 afm, inlet and throttle body the engine will be completely strangled. It would probably run to a degree but it wouldn't be nice.

[Kedge]

Would also make swapping to B25 from B20 a complete wasite of time and effort. They're not expensive parts to buy if you haven't got them. Drop Jim320i a message, I know he;ll have these parts.

[laurencecarter]

Ok cheers. It was only as If I can't get them immediately while doing the swap. Just to see if it would be drive able. Not a permanent fixture.
Thanks

[batleyrhino]

What's the cost for doing a swap from B20 to B25, including the all the necessary parts? I'm thinking of looking for a 320 now and then dropping a B25 donk in it.

[Quaser]

As said before, you will need the afm, inlet, injectors, rubber boot etc - easiest if you can get the whole loom as well and just disconnect from the ecu and pull the wire through - you can get the whole engine out and box out this way within a couple of hours

[Cloggy Saint]

It spirals! I'm slowly doing up a b25 and the original plan was to replace the timing belt, water pump, clutch, all gaskets and a few other bits and pieces. Trouble is when the engine's out and everything's accessible you end up replacing all kinds of other stuff. I've spent about €500 on parts and there's more to come.