E30 Zone

Hello

Im thinking about the 325 engine into a 320 shell.

Im told the engine is straight swap.
are the gearboxes the same? so ok to use 320?

Are the brakes, running gear(front & rear) the same?
What are the differences between the 325 and 320 from standard?

thanks

There is a search facility on this forum.

Ben

What a helpful post^^^^.

The gear boxes are interchangable as far as I'm aware but I think they have different ratios. 325s have rear disc brakes I think, I also think the front struts are 51mm which your 320 might not be. The diff could be a different ratio but can be used still. HTH.

There's nothing like a helpful answer! (do you see where I'm going with this one?)

i know! everytime i seem to search after a couple of pages of looking
it says
No topics or posts met your search criteria, even though it has another 30 pages remaining

hense asking.

Ok, here's a good place to start: http://www.e30zone.net/modules.php?name ... forum&f=28

Ben

aterro wrote:Hello

Im thinking about the 325 engine into a 320 shell.

Im told the engine is straight swap.
are the gearboxes the same? so ok to use 320?

Are the brakes, running gear(front & rear) the same?
What are the differences between the 325 and 320 from standard?

thanks

Engines are a straight swap.
The ratios on the 320 gearbox and diff may be a bit to short for the 2.5

325 has disk brakes on the rear and the larger 51mm struts up front...

dont forget the ECU's

First question is what 320i? It makes a lot of difference if the 320i is a saloon, or one of the 'better' models, such as a touring or a cab.
Tourings and cabs have very similar suspension and brakes to all 325s. Not so for the saloons.
320 gearbox will work OK with the 325 engine, although it is of a weaker (and shorter) design.

Gearboxes are different, though if i recall, the 320 box has the same ratios as per a 325 sport box.
The differential on a 320 is a small case 4.10 where as the 325 has a medium case diff, with ratios usually 3.91, 3.73 (rare) and 3.64 to one ratios.

Brakes i think are different on the front, some 320's i believe had solid front discs over vented, though i could be wrong, and the rear axle had discs on a 325 where as a 320 had drums.

Suspension, stock wise, a 320 has 48mm struts, where as the 325i had the more desirable 51mm diameter struts, which have more options for tuning avaliable.

Edit:
As Brianmoore mentioned in his post, depends if it's a Cab, Saloon or Touring!

Engines:

http://www.e30zone.net/e30zonewiki/index.php/M20

Gearboxes:

http://www.e30zone.net/e30zonewiki/inde ... ain#Manual

Diff:

http://www.e30zone.net/e30zonewiki/inde ... fferential

ECUs:

http://www.e30zone.net/e30zonewiki/index.php/ECU

It's all there, you just need to read it. And the reason search fails after 3 or 4 pages is that you're taking too long to read it all; it times out after about 10-15 minutes.

its a 2 door saloon?(coupe)?

So drums, 48mm strut, weaker box and shorter diff?

Shafts, clutch, flywheel the same?

Recommend upgrading to discs rear?

thanks

All info on the drivetrain is on the same page as the gearbox info.

Info on the Brakes is in the Wiki under, surprisingly, Brakes:

http://www.e30zone.net/e30zonewiki/index.php/Brakes

including a guide on converting to rear discs:

http://www.e30zone.net/e30zonewiki/inde ... conversion

Rich, do you think there is some way the Wiki can be given a more prominent place on the Zone so people think about looking there for information?

I'm as guilty as many others of not using it as a first point of reference!

To the OP, rear discs are a nice to have feature but i'm pretty sure i've read in term of braking power there isn't much difference between rear discs and drums. Obviously from enthusiastic driving the drums will over heat quicker.

Thank you all!
Mucho appreciated.

Thanks kedge too, wanted to know is it really worth it changing to discs over drums.

Kedge wrote:Rich, do you think there is some way the Wiki can be given a more prominent place on the Zone so people think about looking there for information?

Chris put a link on the front page, it's got its own button on the top bar and other people are linking to it too. It's also started popping up at the top of Google searches for quite a few things. But I don't have any power on the actual Forum to make any site changes, unfortunately. Even if there was a comment on the Search page first, I doubt people would read it.

Still, I don't mind showing off our handiwork at every possible opportunity