Engine change?

Post Sat Aug 15, 2009 12:58 am

Hi there, I need a little advise.
Ive just bought a G-reg 320i auto convertible with a nakered engine and want to fit a 325 engine.
What parts other than the engine do I need to get?
The exhaust on the car already has the twin exhaust all the way through, will this be ok for a 325 engine?
Thanks

Post Sat Aug 15, 2009 9:55 am

exhaust will have a bigger bore on the 325 one but should be fine until you get aroundto replacing it but it might strangle the power slightly

Post Sat Aug 15, 2009 12:16 pm

Do you mean the whole exhaust or just the manifold?

Post Sat Aug 15, 2009 7:32 pm

Ironicly, the manifold is identical but the rest of the system has smaller bore pipework than the 325 so it will work but restrict the power a bit untill its replaced.

Post Sat Aug 15, 2009 7:41 pm

whipsey wrote:exhaust will have a bigger bore on the 325 one but should be fine until you get aroundto replacing it but it might strangle the power slightly

stonesie wrote:Ironicly, the manifold is identical but the rest of the system has smaller bore pipework than the 325 so it will work but restrict the power a bit untill its replaced.

Sorry lads, correction required.
The twin 2.0 system is the same bore where it matters as the 2.5 one. The front section is the same for both engines (check ETK if you don't believe me). The only difference in the rear section is the tailpipes - 45mm on the 2.0 (same as the rest of the system), 60mm on the 2.5 - ie, purely cosmetic.
No comparison between the 2 systems if you're talking 3-piece as the 3-piece 2.0 system is single pipe from the front box back. AFAIK, the 2- and 3-piece 2.5 systems are the same diameter piping.

Post Sat Aug 15, 2009 8:18 pm

That's confused me as i had to take the exhaust clamp at the back of the gearbox back to the local dealer as it was too small, they had ordered it from the 320's reg number despite me telling them that the car had the 2.5 exhaust fitted...

Very strange.

Post Sat Aug 15, 2009 8:27 pm

stonesie wrote:That's confused me as i had to take the exhaust clamp at the back of the gearbox back to the local dealer as it was too small, they had ordered it from the 320's reg number despite me telling them that the car had the 2.5 exhaust fitted...
Very strange.

They must have ordered the wrong one in the first place then tried b**ls***ting you.
Your car's a 320i touring, yes?? I've checked ETK and the part number of that bracket is definitely the same for both engines

Post Sat Aug 15, 2009 9:12 pm

Well i VERY rarely use Stratstone doncaster for parts now, they were a bit problematic and more expensive than Cotswold.

To answer the OP's question, you will need...
Engine
Inlet manifold and throttle body
Air Flow Meter
AFM to throttle body rubber boot
Idle control valve if it looks different, if not then keep the 2.0 one
ECU... Or you can fit the 2.0 ECU with a chip from A-TEC to run the 2.5 and add a bit more power too

You will need to transfer the throttle position switch to the 2.5 TB as the automatic TPS is different, the TB will have to come off for this but as long as you dont damage the gasket it is re-useable.

I forgot to add.... And this is very important...

Change the sump gasket before fitting the new engine, they're an easy job with the engine out, but a total cow of a job with the engine in, I've done 2 with the lump fitted (must be mad

)

Post Sat Aug 15, 2009 9:54 pm

StuBeeDoo wrote:
whipsey wrote:exhaust will have a bigger bore on the 325 one but should be fine until you get aroundto replacing it but it might strangle the power slightly

stonesie wrote:Ironicly, the manifold is identical but the rest of the system has smaller bore pipework than the 325 so it will work but restrict the power a bit untill its replaced.
Sorry lads, correction required.
The twin 2.0 system is the same bore where it matters as the 2.5 one. The front section is the same for both engines (check ETK if you don't believe me). The only difference in the rear section is the tailpipes - 45mm on the 2.0 (same as the rest of the system), 60mm on the 2.5 - ie, purely cosmetic.
No comparison between the 2 systems if you're talking 3-piece as the 3-piece 2.0 system is single pipe from the front box back. AFAIK, the 2- and 3-piece 2.5 systems are the same diameter piping.

we learn something new everyday

Post Sat Aug 15, 2009 9:58 pm

whipsey wrote:we learn something new everyday

I've lost count of the number of times I've posted this info!

Post Sat Aug 15, 2009 11:49 pm

Right ive just managed to buy a 325 engine off of ebay and it comes complete including - ECU & loom, crossmember, steering rack & engine mounts. I was the only bidder so I think I got it for a very good price!

Post Sun Aug 16, 2009 8:12 am

stonesie wrote:Well i VERY rarely use Stratstone doncaster for parts now

I don't use Stratstone if I can help it - and I work for the same group!

Post Fri Aug 21, 2009 2:04 am

I've been busy today started the job of removing the engine. Removed all pipes, wires etc etc, now need to unbolt gearbox & exhaust manifold then the engine is ready to come out! Just stuck on the f**king starter motor at the moment as im having trouble getting to it!

I've undone one nut but the bolt is spinning with the nut & I can get a spanner or socket on the bolt on the other side. Any advise or tricks of the trade are appreciated!

Post Fri Aug 21, 2009 9:37 am

Leave the starter where it is and take it out with the engine?

Post Fri Aug 21, 2009 10:25 pm

clarko74 wrote:Leave the starter where it is and take it out with the engine?

Thought it had to come out! Brilliant I will leave it where it is then. Thanks

Post Fri Aug 21, 2009 10:50 pm

andrew320i wrote:
clarko74 wrote:Leave the starter where it is and take it out with the engine?
Thought it had to come out! Brilliant I will leave it where it is then. Thanks

starter bolts locate in bell housing of gearbox so you need to remove them.

Post Fri Aug 21, 2009 10:50 pm

Does anyone know where's the best place to buy a superchip? As I need to change the ECU for the engine change, I thought why it's out I should fit a chip!

Post Fri Aug 21, 2009 10:52 pm

baptie0 wrote:
andrew320i wrote:
clarko74 wrote:Leave the starter where it is and take it out with the engine?
Thought it had to come out! Brilliant I will leave it where it is then. Thanks
starter bolts locate in bell housing of gearbox so you need to remove them.

Dame ok looks like I will have to keep trying to remove it!

Post Sun Aug 23, 2009 12:17 am

Well I collected my 325 engine today and the bloke had some other parts for me to look at. So ended up buying a Mtech 2 front & rear bumpers, Mtech 1 side skirts & Mtech steering wheel aswell as the engine! My otherhalfs Zafira was full to the brim

Won't be useing the Mtech 1 sideskirts though as I want Mtech 2 side skirts to match the front & rear bumpers. So if anyone wants a pair of Mtech 1 side skirts, make me a offer.

Post Sun Aug 23, 2009 7:14 pm

If it were me,I would take engine and 'box out as a lump and swap the gearbox on the garage floor...starter bolts can be reached with the aid of a looooong extention bar and an assistant to guide it into place,still not easy,though.

Post Sun Aug 23, 2009 11:21 pm

Will have a look under the car again & if it does look easier then I will remove g'box & engine as one! Thanks
Can anyone tell me if the rocker covers on the 320 & 325 are the same? I hope they are as the cover on the 320 is polished & want to put it on the 325 lump!

Post Mon Aug 24, 2009 12:03 am

Defo take the engine and box out in one, then split them on the floor. Its much much easier.

320i and 325i rocker covers are the same.

Post Mon Aug 24, 2009 12:31 am

Ok will take engine and gearbox out as one then! Great I'm pleased the rocker covers are the same, will get the polished one all polished up before fitting it to the 325 lump then!