daimlermans new engine

[daimlerman]

Regular readers of these pages will remember that I fitted my lachs 4 door 320 with an eta bottom end mid summer.Then the 325 head cracked and I fitted a standard 320 head with new valves and guides.This sorted the water/oil mixing but did nothing for the oil consumption.As the summer turned to winter so the oil pressure fell away until the point was reached when the oil light was on below 1500rpm.This was accompanied by a death rattle from the nether regions.I started to gather up all the bits that I would need.A zoner offered a used 325 block at sensible money,I found a themostat housing with a working bleed nipple on ebay and I also bought a s/hand engine crane.It cost me £75 to hire a crane last time so I reckoned I could buy one then sell it after the job was done and save a bit of cash that way!(I am known for being tight fisted)I felt that the most difficult part of stripping the engine was loosening the front pulley bolt,I knew that with the engine out I would not be able to stop the block rolling whilst putting enough leverage on the bolt.So I took the rad and the plastic undertray out to give access,a deep 22mm socket,all my extention bars and two lumps of 4+2 timber to hold the bars almost horiziontal,took the H/T lead off the coil and flicked the starter.The bolt came free on the 4th try.After that,it was just time and careful dismantling till I had the crank in my hands.At the engine shop there was much sucking of teeth,but the crank could be reground.This,along with new rings and bearings cost a little over £300.Gaskets,head bolts,new exhaust brackets and a few other oddments from GSF was another £100 or so.Oil seals,big end bolts,flywheel bolts and gearlinkage bits from the stealer took another £120 from my flexible friend.Reassembly went well(this is the 1st time I have taken an engine this far)I had fitted 4 pistons before I saw the tiny word top on the upper side of the top ring,just hope the first 4 went in the right way up..I debated with myself the merits of more work on the 320 head(325 valves,three way cut on the seats,polishing)but decided that I would wait and see if I could cope with this power increase first.I have used a 325 inlet manifold this time with 325 injectors and a zone chip was fitted last time.I have now run about 1200miles.First 500 at no more than 2000rpm,oil/filter change;then I have slowly built up engine speed a little at a time.So far I have added no oil,the temperature remains steady in the middle of the gauge and consumption of super unleaded is 33/35mpg.I am now starting to think that I have got it right this time....pulls strongly from 2000rpm.Anyone any thoughts about higher gearing?Different diff or 15in rims?I am not looking for a racing car,just something discreet but quick..thanks to all zoners for your help with this project,knowing you are not alone has helped me no end!

[Pikey]

Having seen the inside of my last car's engine (a Skyline) I know where you're at, and how satisfying a feeling it is to have built an engine yourself

Begs the question though - why didnt you just get a new engine? Wasnt an option for me (a complete running RB26 is about two grand, and quite rare to find one too )

[Herrity]

How about a genuine 325i sport gearbox where the first 3 ratio's are slightly different to a normal one and a diff of a ratio I wouldn't have a clue to suggest, all subtle mods. While you're there, what exhaust are you using ? How about a nice system, it doesn't have to a straight through, no baffle look at me system, just a nice one that works high up the rev range. All cheap (ish) mods there.

[daimlerman]

Pikey,This is a 2.7 in a lowish state of tune...at the moment.Herrity,I like the idea of a sport box,it is typical of me to learn about these things after I have had the box on the garage floor.Exhaust is standard mild steel twin pipe with cast manifold,I would love a s/s manifold but I cannot get the folding from er indoors....yet!

[Pikey]

Ah, 2.7, fair enough. Doesnt say that anywhere

[daimlerman]

eta bottom end is a subtle clue,pikey....

[Templ8e30]

Hi buddy, I'm glad the block worked out ok for you

I find my 3.73 diff runs great with my pre-facelift 325i gearbox, I did have a 3.91 diff but the 3.73 feels better. The 2.7 seems to like a lower gear for the torque to 'bite' into.

Cheers,

Iain T