What could be the reasoning that BMW didn't make the n54 heads flow better like could the higher velocity tumble more and have a better burn at moderate power levels? Like how much does head porting usually help?
That's some of it.
The bigger reason is their goals were only in the 300hp mark. The more you open up heads/valves the more you hurt response and low end power.
Think reason for cams not being common is people usually don't crack a block unless they have to, also im sure the long warranty on turbos and hpfp doesn't help, last is vanos and the dme not being cracked early on. I grew up on heads, cam, msd ignition, as your first real power adders and gears and shifter. Turbos from factory have really simplifies the formula but if people like you can pave way things could get interesting.
That's a question that's always been in my head too - I think it's a combination of the fact that it's harder to DIY, and that having two cams means it's more expensive. Even on older, single-cam platforms it was really still the dedicated people who did cams, not just your typical FBO stoplight-to-stoplight racer. With all these new engines having two+ cams and VVT, it seems like they're getting less popular in general honestly. Even the mustang guys hardly swap cams on their shiny new Coyote's, but on a foxbody that was the difference between "finally bought my highschool dream car" and "gearhead with a problem"Also keep in mind that a ported head and bigger cams go hand in hand, i.e. for best results you want both combined together. Doesn't make sense to me why upgraded cams are such a rarity on this platform despite being a FAR superior bolt on to something like a Docrace IM from a whp/$$ perspective. Might be the relative difficulty of a DIY install perhaps?
I have the N53 head installed, and (very) soon to be running on my car. Here is a brief rundown of what needs to be done to get this to work.
a) first and foremost, an N53 head needs to be sourced from Europe. Note that these weren't all that common to begin with...
b) several water jackets need to be welded shut and port-matched to an N54 HG, and the oil drainage holes need to be enlarged as well
c) head bolt holes are 1mm too small, and N54 head bolt washers are too large and need to be machined down
d) There is a 19mm hole/fitting in the back of the head that needs to be plugged
e) exhaust ports are completely incompatible with anything N54-related, so a suitable solution will need to be devised here
f) inlet ports have no drillings leading to the valve cover ports, so an external low-side PCV solution will need to be rigged up.
g) all other parts (intake manifold, cams, ledges, seals, valve cover, etc) fit with no modification
In all, it was a lot of work. And I don't think the effort is justified for anything but the most hardcore of builds, especially since most forum members here have head porting options available to them locally. Before you ask, I did not take any pics of the process above. I will however, share pics of my completed setup within the coming few days, in a separate build thread...
FWIW running an N52 head properly would be the same deal, with the addition of the following
a) standalone ECU
b) milling the valvetronic bridge and fitting an intake cam ledge with some proper cams
thanks for the info , i purchased an n53 head myself should be here soon BUT you lost me at E..so youre saying the ports itself are completely different or just the bolt pattern on the exhaust manifold? can you elaborate more on this, thanks !