new to bm's.. what conversions are quick and easy?

[Barton]

Hey people,

recently bought an e30 with a high mileage m20b20 engine

following it overheating/rad splitting i'm doing a service on it, but can help but keep thinking about more power

what is the simplest conversion that could if i had all the parts be easily done in a day for not much outlay?

i'd assume the m20b25 engine is the obvious choice, and presume all i need is the engine and the ecu?

as everything should be like-for-like?

if i fit the 2.5 what else should i look for if i find a donor?

alternatively, what else is out there to suit my needs?

thanks.

[eta]

It depends on what year the 320i came from. Really You will need the engine, loom, ECU, fuel rail....
Ideally you should change the gearbox, prop and diff for it all to be correct. Really buy a 325i instead it will be cheaper and less faff.

Ensure the M20B20 is performing as it should first by doing the valve clearances and a proper service. A suspension refresh to tighen everything up. These things should be the first things to do.

A 320i is not that slow if it's running right.

[StuBeeDoo]

A 320i is not that slow if it's running right.

..... and you keep the revs above 4k.

If you can find an eta 2.7 bottom-end, the 2.0 head will bolt straight on and all you will need to source would be a chip (Ant at ATech is your man here) and a set of injectors, 3bar FPR, inlet manifold, AFM and TB all from a 325i. Hey presto! A nice torquey motor that will pull very well from under 2k to past 6k.

[Barton]

its a 1989 model

is there anything plug and play?

i still think the 2.5 will be the easiest conversion, and hopefully give me the power i need and the better fuel economy when i need it

[leeparkes]

M20 2.5 is probably the easiest swap you can do if your starting with a 2.0 as there virtually the same engine, and it will be plug & play.

[StuBeeDoo]

is there anything plug and play?

M20B25 is what you want then.

[ross2009]

defo the 2.5 but keep in mind the diff and prop on the 2.0 is different

[StuBeeDoo]

defo the 2.5 but keep in mind the diff and prop on the 2.0 is different

If he's planning on using the 2ltr gearbox (no problem with that, plenty of people are using one on the back of 2.7s and 2.8s), he'll have virtually the same ratios as a Sport 'box and he won't have to change the prop - just the diff.

[ross2009]

very true stu

[Barton]

i was planning on changing diff anyway as i want an lsd

doing gearbox/prop isn't the end of the world, i'm sure its easy enough

realistically just need to find myself a cheap rotten or written off 325i