320i 2.7

[jay528ise1985]

I'm going to make my 1989 320i a 320i 2.7 and have a few questions. If anyone can answer them I'd be grateful!

The 325i's have oil coolers - Is there an adaptor between the block and the filter that I can fit to my 320i?

Will the radiator from a 325i with air con fit into mine? I'm keen to make sure the cooling system's up to the job of cooling a 35% larger engine with higher compression.

Is there a difference between 320i & 325i clutches, and if there is will a 325i clutch fit between the eta output shaft and my manual 'box?

Will Ant be able to do me a chip that suits this setup i.e. 525e bottom end, 320i top end, standard 320i dual exhaust, inlet manifold and camshaft? I'm going this route because I'm more interested in a wide torque band than outright power.

Any help gratefully received!!!!!!!

[Ant]

For the oil cooler rob the sandwich plate and plumbing from a breaker, flush it out and retro fit, it bolts where the filter currently sits, TBH you wont need the cooler though.

325 A/C rad will fit but get the fitting for the front bulkhead or it will have nothing to fix too

use a 325 clutch mate, 320 units are very similar but not up to the task IMHO, all can be interchanged , dont forget you'll need the spigot bearing fitted in the ETA crank !

use 325 manifold TB and injectors, the 320 injectors are 129cc/min, 325 are 149cc/min, the bigger pleumn and TB from the 325 are , I'd say a necessity, I can see where you're coming from with regard to the narrow intake promoting torque though.

as for the chip, gimme a yell when you finalise the spec and we'll sort something special for ya M8

[jay528ise1985]

Thanx for that - Nice to know that there are others on my wavelength! All my mates think I'm a loony and tell me to get an E36 - NO chance.

Just a couple of small q's - Will the 325i injectors fit into the 320i manifold and will a 325i throttle body fit onto same?

(Reason I wanted to know about oil cooler fitting was because I was thinking of getting a 325i automatic & air-con radiator & plumbing the oil cooler hoses from the engine onto the connections at the bottom of the auto radiator - It'll keep the oil at same temp as coolant methinks..., Just an idea I had!)

[Templ8e30]

Hi Mate, I've just finished building a 2.7 from a 320i and will be fitting it this week.

I used a eta bottom end with a highly modded eta head but the 320i head is also good, 325i injectors/inlet manifold and throttle body.

The 320i inlet can be modded to accept a 325i TB, drop me an email to templ8(at)hotmail.com and I'll send you the article that I wrote a while back.

The 325i clutch is the same diameter as a 320i clutch but the 2.5 pressure plate has greater clamping force.

I would also change the diff as the small case 320i diff is not really up to the extra torque, I've also fitted a 325i gearbox.

The 325i exhaust is a good idea too.

I'll be writing a full report on this mod when I'm satisfied with the way mine is running.

Cant wait to get it all fitted and fired up

[jay528ise1985]

Thanks Ant & Templ8!

I eagerly await the report on your 2.7 conversion templ8, and what sort of mod's did you do to the eta head (it's the same head as in the E21's isn't it?). I understand that the eta head has quite small ports & valves which is why I'm sticking with my 731 head.

Did you have to match the ports to the 325i inlet and exhaust manifolds?

[Templ8e30]

Jay, I ported the inlet and exhaust to the 325i sizes (lots and lots of ally to remove) and had 3 angle valves / seats cut.

The Eta uses 4 cam bearings whereas the 320i/325i use all 7. The Eta head has all 7 bearings in the casting but only 4 are drilled for the oil feeds, I drilled these out to match the other 4.

The valves are the same diameter as the 731 head anyway so I didnt fit bigger ones, the 325i uses a 1mm larger inlet valve.

Took me 4 hours this morning to get the old 320i engine and gearbox out from start to finish, pretty good considering it was a runner last night .

Engine bay will get a damn good clean while it's empty.

Just been swapping stuff like flywheel and sump etc ready to go back in tomorrow.

Need a good soak in the bath now to ease my aches

Cheers,

Iain T

[Boots_Walker]

very keen to hear your impressions of the 2.7 Iain