Little bit of advice pls for newbie 320i auto to....?

Post Fri Sep 04, 2009 4:20 pm

Hi all,

This must have been covered to death but after a lot of reading I figure the easiest option is to fit a complete 325 engine with manual gearbox. Feel free to offer any alternatives.

My question really is what I can get the doner engine out of and which year/age is the best. I've got a 1986 320i so not sure if that makes a difference on the loom side of things etc (i think mines jetronic? instead of the later bosch is it?). Will I have to change the loom whatever?

What engine can go straight in? (just 325's or 525's etc)

Cheers for any advice!

Chris

Post Fri Sep 04, 2009 4:34 pm

if it's an m20b25 you want then have a look in the for sale sections & try pming a few traders on here as i'm sure they'll be able to help you.

have a look on ebay as you might find a scrapper on there that you could break for the parts you need.

Post Fri Sep 04, 2009 4:48 pm

Cheers, eyah i think the m20b25 is the one i want unless there is a better option!

Is the M20B25 the only one that will go straight in? And did they only put those in 3series or are there some in 5series with same moutning points etc?

Post Fri Sep 04, 2009 5:00 pm

Just compenting as im thinking of doing it to my 89 320i, just wondered how hard it is and how hard ecu to set up!

Post Fri Sep 04, 2009 5:03 pm

the ecu should be a straight swap (but don't quote me on that).

wait till mr moooooooooooooore turns up then ask him.

Post Fri Sep 04, 2009 5:06 pm

might be worth trying to pick up a mot failure 325 or one thats rusted as you may find you need more bits than usual like the manual pedel box, linkage, prop?? and clutch pope work... just an idea

Post Fri Sep 04, 2009 5:09 pm

appletree wrote:might be worth trying to pick up a mot failure 325 or one thats rusted as you may find you need more bits than usual like the manual pedel box, linkage, prop?? and clutch pope work... just an idea

yes thats what im thinking but im not fussed if i keep it auto to make it simpler but would be good to have a running doner car

Post Fri Sep 04, 2009 5:12 pm

i'm off to louth on monday so if you want i'll pop into the garage who look after my sport & have a word with them & see if they know off any 325's going cheap & if they do i'll get the details off them & post them up.

steve.

Post Fri Sep 04, 2009 5:17 pm

Top man Steve.

I've just read that if fitting a later (post-facelift?) engine it will run on motronic rather than jetronic so that will need to be changed. Is the easy option to get a pre-facelift 325 (with higher compression) with the jetronic system. I understand the jetronic can't be chipped etc but does the high comp M20B25 engine (180bhp?) give the same power as say the lower comp (170?) with a chipped motronic system. Or are all 325's motronic?!

questions questions!

Post Fri Sep 04, 2009 5:21 pm

no worries fella.

regards the ecu (jetronic/motronic) well you're asking the wrong man there,

Post Fri Sep 04, 2009 5:24 pm

haha - open to everyone!

Post Mon Sep 07, 2009 1:40 pm

Cheers willnz,

I'll look into that. Can i get the engine out of any model car to go straight in, 3series and 5series? any others?

Post Mon Sep 07, 2009 11:17 pm

allstar_07 & n88byn been to the garage that look after my car today & at the moment they don't know of any 325's going cheap (mot failure) but as soon as they do they'll let me know.

sorry about that fella's

Post Mon Sep 07, 2009 11:22 pm

Nice one, will start to save some pennys lol

Post Tue Sep 08, 2009 11:46 am

Cheers 325msport, appreciate it.

In the meantime can anyone give a list of models and years that would be a suitable donor?

Post Tue Sep 08, 2009 12:50 pm

I believe Jules (SPADGE) on here is good for all this and will even do the job for you (without costing an arm and a leg!).

Its wise to get a donor 325i. Just try find a pre-facelift for a tiny bit less hassle, but the engine blocks are the same (basically...), but its the other little parts that are different. Fuel Injection system, cooling etc.

You should be able to use your 320i auto cooling iirc, but 325i cooling would be better.

These engines will not have the stated bhp as they do wear down over 20ish years!

Also, be prepared to reserve some pennies for engine problems you may get after the swap. If you can afford it or do it yourself, pull the donor engine apart, clean it all up and rebuild the cylinder head with new gaskets and tighten up the rockers. New oils throughout. A waterpump, tensioner and cambelt, possibly a new rad should be considered.

Lightweight flywheel whilst your there???

.

Depends on the budget fella, but give SPADGE a pm. He does this on a regular basis I believe and sells "325i conversions" as lots with everything you'll need. As I said, he may even fit it for you!

Good luck.

Post Tue Sep 08, 2009 2:16 pm

Thanks Nay for the advice - a donor is the way forward but I'll PM spadge again.

This still hasn't been clarified but would a pre-facelift 525 have the same engine/loom combination as the 325 - i.e. it will go straight in?

Post Wed Sep 23, 2009 11:55 am

re-visiting this....

As the M20b25 is the most common conversion there seems quite a lot of competition for them!

Whats the next best alternative, weighing up cost,power,economy,ease of swopping etc? M50?

Also can the 2.5 from a 5series of same age go straight in - is this being not answered because it'll make people buy those up too?!

Post Wed Sep 23, 2009 12:38 pm

Thanks will,

Was the M20B25 only put in the 5 series from 88-90? Is the gearbox/prop etc all the same? Any ideas on gear linkage and pedal set? Would a sump and other bits from a M20B20 fit?

just a few questions!

Post Wed Sep 23, 2009 5:46 pm

There are a few good conversions available, but again, competition arises with all of them.

If your willing to pay £200/£250 for a good running engine, then just be the first inline for a B25.

Otherwise, if I was fannying around fitting a non E30 engine, it would be an M30 or an S50 or the likes.

Post Fri Sep 25, 2009 2:44 pm

Thanks again Will