BMW Series E46 330i Cylinder Head Porting

[DamirGTI]

Hello !

At last , i have an project to make :)

It's a straight 6 cylinder head , 4 valves per cylinder , 2,979 cc 230 hp @ 5,900 rpm from BMW E46 330i car .

Engine code : M54B30

From a rough eye/finger inspections of the ports and valve pockets , i have to say i'm pretty disappointed by the port casting/indexing as being a BMW head i supposed it would be much better . So , i see here's a lot of job and also , good end result when finished with the porting .

Inlet ports are a bit narrow , lots of sharp edges inside the valve pockets and i think i'd lift up the inlet port roof around the valve guide as it seems to me somewhat bad , which i think will improve swirl effect .

Exhaust ports , even more narrower than the inlet all around on the port entry - lots of material till the gasket sealing area .. and again sharp edges inside the valve pockets (but not as much as on inlets) , and similar "hump" around valve guide .

SSR (Short side radius) , not bad on both the inlet and exhaust , think i'll do just some smoothing here ..

Combustion chambers , nice and smooth finish from factory .. just some sharp edges around valve seats which needs removing and smoothing , so not so much job here :) (not sure if it's worth doing valve unshrouding ?)

The head i'm preparing is for one very good friend of mine , so i want do it as best as i can !
Modifications further will be higher compression ratio , he said to me that he wants to retain standard valve sizes (will measure) , standard camshafts , inlet and exhaust manifold . So just porting and cutting multiple angle seats .

Im currently in processes of dismantling the valves , cleaning etc. .. when i finish that i'll post pics of the head .

Till then , i have some cut offs of this the same head :










Any advices much appreciated :)

Thanks

Damir

[DamirGTI]

.. removed the valves and pre-cleaned (will clean it up with my trusty method soaking with Acetone and Xylene mixture over night)

Som pics of todays work :

Head with valves removed



Inlet port side




Exhaust port side




Combustion chamber


Valves


Inlet valve


Exhaust valve


.. and some evidence of oil residue on the inlet valve (leaky valve steam seals)


Damir

[DamirGTI]

Started a bit yesterday on valve pockets :

Inlet


Exhaust


Damir :)

[DamirGTI]

Some more pics of the head :

Exhaust valve pockets




Inlet valve pockets




Inlet and exhaust pockets


Inlet port with clearly visible casting/port indexing imperfections








Top view , head base :


.. and i have one question , can i grind off this marked hump on the top of the inlet port entry's or is it needed for something like diverting air to the valve pockets ?


Thanks :)

Damir

[DamirGTI]

Some more pictures :

Exhaust port exists and valve pockets







.. and some of today's work on the combustion chambers (but not finished yet , still in the process ..)

Standard/factory shape of the combustion chamber






Reshaped combustion chambers (but as said , not fully completed yet ..)










So , i was concentrating just on smoothing the ridges around valve seats and around the center where's the spark plug .

Damir

[DamirGTI]

And my thoughts about valves unshrouding vanished as soon as i saw this :

Top inlet valve seat region


Top exhaust valve seat region


.. both surfaces cleared off the ridges but - there's virtually no "room" for valve unshrouding !

The gasket sealing area is really close to the valve seat region , especially around exhaust valve seats .. as it can be seen on the pictures .

Inlet




Exhaust




That will be for the safer route i wont do grinding any further than this , cos head gasket fire ring markings are so close and grinding more than this will for sure end up bad for head gasket sealing the combustion chambers .

Damir

[DamirGTI]

Some of today's work on the first cylinder ports/valve pockets :

Inlet








... casting imperfections removed/smoothed , and already it looks much better - not completed yet .

Exhaust









(can i grind off all this area around the exhaust port exists till the gasket markings , and if so - radiused or flat ?!)



.. did the same/similar job as on the inlet , and also - not completed yet .

Top view



And , please i need some info/help/guidance - good ? bad ? ugly ? .. anything , cos i feel like a ghost here posting tons of pictures and explanation what i did and where :o| ... and i don't want to screw up something .

Thanks !

Damir

[DamirGTI]

From the first top , center cut of the head , i opted to do modifying this head as it can be seen on the red markings :



Am I missing something ?

Damir

[DamirGTI]

Started with opening up the exhaust port exists today .

I opted for a radius shape , rather than flat grinding from the exists to the inside of the ports , and also i haven't been doing reshaping much on the floor of the port exists but concentrating on widening and lifting up the exists up and sideways radiused at 20/25 deg. then blending inside the ports :










Here , you can clearly see the difference and how the stock port exist is quadrant shape and narrow :

Stock port exist shape and modified/radiused


Also , did the similar on the inlet port entry's , but there isn't so much material till the gasket sealing surface so i just made it a bit ovaled shape - sideways and roof of the port entry , haven't touched the floor of the port entry's :


Damir

[DamirGTI]

Right , some more interesting thoughts - material adding .

SSR (Short Side Radius)

On the both sides , inlet and exhaust - looks like this head might benefit by adding the material on the SSR surface in order to create an "venturi effect" .

Why ? , well me thinks that its too flat when looking from the ports then following the floor lines to the SSR which then blends into the valve seat .
By adding the material on this areas , on the inlet the air/fuel mixture i assume will turn up more progressively along the SSR and into the combustion chamber .. particularly on low revs when the air/fuel mixture mostly travels along the floor lines of the port .
Looking at the stock factory shape of the SSR , it seems that the air/fuel mixture will (on low revs) , while traveling trough the floor lines create turbulences by bouncing on/around the valve .

Exhaust area as well , adding material for more radiused floor shape along the SSR which could assist exhaust gases flowing faster out .

Right or wrong ? if so - how can material be added ?

I have 2 pack epoxy aluminum resin , but not so sure if it will hold on well on the surface .

Damir

[DamirGTI]

So like this :



Red lines - modifying
Yellow lines - material adding

Damir

[DamirGTI]

Testing ... :

[DamirGTI]

.. started with finishing :
















And time for a brake , cos this hurts :o/ :



Damir

[DamirGTI]

.. almost there , but there's so much job on this cylinder head - tons of hard labor hours , for finishing this one :o|





Damir

[DamirGTI]

Next step - decided to take this job all the way till the maxi .

Will add material in inlet ports/throats , using aluminum epoxy filler/putty (Loctite Hysol) .

I made an test , in order to be double sure that the epoxy which i'll be using is good enough for the job :











It needs up to 72h for the epoxy to fully cure/harden , and i tried all kinds of stuff during the inspection of the epoxy adhesion on the surface - trying to dig the epoxy from the surface by hammering it off with an big sharp chisel and hammer , tried heating and then digging up again etc. etc.

The test provided that , when the surface is well cleaned (myself i'm using 99% Acetone) and prepared with 60 abrasive grt. paper , the adhesion on the surface is almost "rock solid" .

However modeling added material will be a little tricky job , so not so easy defiantly .

Damir