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?
N52 head swap, injection and vanos controls
- Thread starter Reaper0995
- Start date
I believe the injector takes up space that valves would normally use but someone can correct me if I'm wrong. The non direct infected engine would have bigger valves and flow better.
Edit: @doublespaces mentions it on page 1.
Edit: @doublespaces mentions it on page 1.
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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.
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.
I'm guessing they designed the head the way they did to help generate torque (thus spooling the turbo) at 1500-1700rpm. Head porting would help the top end immensely if the rest of your setup is up to par. If you want proof, just look at Honda S2000 motors, which put down ~700whp @ just 18psi with a well-sorted kit...
N53/N55/S55 heads use slightly larger valves than the N54, while still retaining DI. N53 even uses the same Piezo injectors...
Agreed!
So for street purposes unless hitting limits of a big turbo it seems like porting could be counter intuitive correct ? Say someone with gc or gc lites would prob have better torque curve on stock heads and really not lose much up top or even at that level top end would see big gains on this platform ?
Not at all actually, a ported head would offer huge benefits to even a stock turbo car, and on aftermarket turbo(s) the gains would be seriously staggering. They would come at a cost to response and low end torque, but IMO the trade-off would be well worth it.
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?
To illustrate the importance of good head flow further; here is a dyno sheet of an N53 Euro 330i with longtube headers, aftermarket intake/airbox, N54 intake manifold , and a tune. Notice how flat the torque curve is, and how it just keeps making power. My guess is they could have extended the redline to 7750 or even 8000 and cracked the 100PS/L mark -and this is still on stock (N53) cams mind you. Now imagine this setup boosted, with a free-breathing exhaust side... (i.e. not hybrid turbos)
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.
IMHO replacing valve guides seals on these motors is an absolute must on all but the latest and lowest mileage N54s. Prime time to install cams while you're in there, and maybe fresh cam ledges as well if you have a higher mileage motor... Trouble is, I count ~$2750 in parts alone to do the job not including labor or special tools, and that's assuming low-lift cams and stock valvetrain (which I am running)
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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"
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 !
Both, you need a new exhaust manifold. Ports are bigger and bolt pattern is slightly different.
Build thread/more details to come this weekend...
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yup got it! hydra gave me all the info i needed
Good to see you my man. Very nice manifolds to match the ports size and shit.
