Crankshaft Knife-Edging

[LumbChuck]

Has anyone ever had a crank "Knife-Edged" ? Just wondering if it is worth the $$$ and does it really help any ??

 

[xarewhyayen]

Has anyone ever had a crank "Knife-Edged" ? Just wondering if it is worth the $$$ and does it really help any ??

Never had it done nor known anyone who has but in theory, its a very good thing. Knife edging does 3 great things.
1. Reduces rotating inertia making the motor lighter and making it easier for the crank to turn.
2. Makes the crank more aerodynamic inside the crankcase cutting down on drag as it spins.
3. Reduces oil Windage to decrease the risk of whipping and possibly foaming the oil in the crankcase.

It HELPS to make higher rpms safer if balanced well. I think its a pretty damn cool upgrade.. not sure what it costs though for our crank. I'd be interested in hearing from someone who got it done to a 7m though. Hope the info helps.

 

[Doward]

Pagin' Ian... IJ please step forth

http://www.mkiiitech.com/forums/viewtopic.php?t=851&postdays=0&postorder=asc&start=645

5th post down

 

[boostinsupragirl]

i have one in my talon and it seams to be fine:icon_bigg

 

[phoenix6]

That crank looks SICCCCCCCCCCCK.

Maybe thats what Ill do in my GTE build if I dont go 1jz. I cant wait to boost.

 

[Doward]

That's exactly what I'll be doing, when I rebuild my 7M - although, I may be destroking it slightly as well

 

[mattjk]

IJ"s is nice because it's still balanced as a whole unit, but this is a bad example of knifeedging:

WAY out of balance and will destroy itself over time at high revs.

 

[supra90turbo]

matt: is that a 4g63 crank?

 

[Adjuster]

Mine is knife edged. Looks like all they did was mill down one angle on the counter weights. (Still works however, and this allows it to still be balanced even with my rods and pistons.)

Here is a shot of my stroked crank and the knife edge. Also note that the oil pump drive is machined down to clear the Pauter rod shoulders.

 

[jimi87-t]

Kind of on the same subject, does anyone know about crank scrapers and if they actually benefit in any way?