Ported Head

ibasniper said:
Has anyone ever ported and polished a M54 head??

is it worth doing ??
Click to expand...

I shouldn’t think it would produce much, modern cylinder head design & manufacture doesn’t leave casting marks etc to tidy up like days gone by and the valve seats won’t be shrouded either. Same goes for head skimming, compression ratios are optimised for pump fuel.
Specific outputs are much higher than they used to be decades ago & cant be easily tweaked like before :thumbsup:
Rob
 
Apparently the castings are really poor, so that there is bigger difference in power for the M models.
Polishing and porting when combined with high lift cams should make a difference. A big valve head would make a bigger difference but looking at images there doesn't seem to be any room.
Many moons ago I had a mk1 fiesta xr2, standard hp 84, I had rallytune of Burnley build me an engine, ported, polished, big valves, high lift cams and twin Weber's....hp 148! Sure left many 16v golf owners wondering what was wrong with their cars!
Anyhow for how to follow this link
http://www.guy-croft.com/viewtopic.php?t=3094
 
Davz said:
Apparently the castings are really poor, so that there is bigger difference in power for the M models.
Polishing and porting when combined with high lift cams should make a difference. A big valve head would make a bigger difference but looking at images there doesn't seem to be any room.
Many moons ago I had a mk1 fiesta xr2, standard hp 84, I had rallytune of Burnley build me an engine, ported, polished, big valves, high lift cams and twin Weber's....hp 148! Sure left many 16v golf owners wondering what was wrong with their cars!
Anyhow for how to follow this link
http://www.guy-croft.com/viewtopic.php?t=3094
Click to expand...
An interesting read. :thumbsup:
 
Thanks for input guys. I may try and find a head somewhere and take a look at the casting and see how bad it is.

I was wondering if porting was worth the extra effort If i to do a engine rebuild. But i don't want to start a can of worms...
 
Davz said:
Apparently the castings are really poor, so that there is bigger difference in power for the M models.
Polishing and porting when combined with high lift cams should make a difference. A big valve head would make a bigger difference but looking at images there doesn't seem to be any room.
Many moons ago I had a mk1 fiesta xr2, standard hp 84, I had rallytune of Burnley build me an engine, ported, polished, big valves, high lift cams and twin Weber's....hp 148! Sure left many 16v golf owners wondering what was wrong with their cars!
Anyhow for how to follow this link
http://www.guy-croft.com/viewtopic.php?t=3094
Click to expand...

No testing results at the end of the thread, it’s easy to make things worse without flow benches or rolling roads to verify gains or losses. Sometimes smaller ports are better than large ones for air velocity/torque output.
It’s the same with camshafts, vanos gives you the best of both worlds really, variable valve duration according to rpm gives an engine with a good spread of power and road manners :thumbsup:
Rob
 
Have a look at CNC Heads they have a price list and the S54 is on it, along with some other BMW’s

Doing it this way the machining is to a standard as a posed to the skill or lack of it when doing it by hand.
 
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