https://www.pureperformancemotorsport.com/index.php/bmw-n54b30-335i-turbo-billet-crankshaft.html
Anyone know anything about these? I guess my first question is, has anyone ever heard of a crank failing from excessive power?
Pure Performance Motorsport Billet crankshaft
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https://www.pureperformancemotorsport.com/index.php/bmw-n54b30-335i-turbo-billet-crankshaft.html
Anyone know anything about these? I guess my first question is, has anyone ever heard of a crank failing from excessive power?
I saw this and couldn't think of any failures from the crank itself. It is promising though to see products like this, though a billet block with floating darton sleeves might be needed before a billet crank!
Anyways, here are some interesting reads.
http://www.speedtalk.com/forum/viewtopic.php?p=9123
http://www.epi-eng.com/piston_engine_technology/crankshaft_design_issues.htm
I would have thought a billet crank might be best for this engine if it was destroked... but after looking at piston speeds and playing with the bore stroke ratio, there isn't any real gain from reducing stroke to increase rpm. If only BMW would have increased bore spacing, it would be possible to increase bore size, reduce stroke, and achieve higher rpms without increasing piston speed. But with narrow cylinder spacing and an undersquare engine, we are kinda stuck with a lower revving engine without flexibility to mess with boring or stroking.
References for those who are interested.
https://en.m.wikipedia.org/wiki/Stroke_ratio
http://www.csgnetwork.com/pistonspeedcalc.html
The n54 has a bore of 84mm and a stroke of 89.6mm. That results in a piston speed of 4115 FPM at 7000rpms. For reference, a hayabusa motorcycle has an 81mm bore and 65mm stroke for a piston speed of 4600 FPM at 10,800rpms.
Anyways, here are some interesting reads.
http://www.speedtalk.com/forum/viewtopic.php?p=9123
http://www.epi-eng.com/piston_engine_technology/crankshaft_design_issues.htm
I would have thought a billet crank might be best for this engine if it was destroked... but after looking at piston speeds and playing with the bore stroke ratio, there isn't any real gain from reducing stroke to increase rpm. If only BMW would have increased bore spacing, it would be possible to increase bore size, reduce stroke, and achieve higher rpms without increasing piston speed. But with narrow cylinder spacing and an undersquare engine, we are kinda stuck with a lower revving engine without flexibility to mess with boring or stroking.
References for those who are interested.
https://en.m.wikipedia.org/wiki/Stroke_ratio
http://www.csgnetwork.com/pistonspeedcalc.html
The n54 has a bore of 84mm and a stroke of 89.6mm. That results in a piston speed of 4115 FPM at 7000rpms. For reference, a hayabusa motorcycle has an 81mm bore and 65mm stroke for a piston speed of 4600 FPM at 10,800rpms.
I use these people for rods and pistons. I will talk to thomas this week and ask why he designed these!
He builds a lot of these engine for abu dabi apparently.
He builds a lot of these engine for abu dabi apparently.
OEM stroke, and it doesn't look like they did any modifications to the nose where the crank hub / timing gear is affixed... kind of a moot point especially since no one has broken an OEM N54 crankshaft yet even with the insane single turbo builds, so why would you buy one with the same specs as OEM
Only think I can think of is weight. Did they remove weight from the assembly? Also, the counterweights are mildly knife edged...which will cut down on windage and aerodynamic losses in the crankcase. Could this to be to help high HP random misfires as well?
I just don't understand why they bothered designing this, if it were a stroker crank I bet a lot more people would be interested
Just be a good co-worker.. Order one! If he had to tell you to do everything you wouldn't be so great lol..
Looks like they offer a crank hub, pistons and rods, I wonder if there are any cars out there using this stuff, and if this actually stops the hub spinning issue?
That type of one piece hub will do nothing. That is exactly the wrong approach without it being keyed to the crank. The way Rebello does ours is genius and uses a stock hub. The Maximum PSI will fix the issue, but you are required to drill the crank, so for people doing it in the car, it's a major hassle.
Maybe it's keyed on the aft side of the hub? I agree though that using a key is the best way.
Keyed on the aft side of the hub? What would that do. Have you had one of these apart in your hands? There is a reason all those original designs Gintani, and Maximum PSI tried failed. Including Gintani’s one piece design. Making it a single piece literally fixes nothing, without it being positively secured to the crank
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