StanRS

Hello :P

First of all, i've used search, but i need more opinons about that item.

My motor build planning 550-600hp, deciding on turbocharger now. Pistons (HKS 85,5), rods (carrilo), bearings (ACL) and stuff is already at my garage. Suddenly i'm understand that my crank isn't in perfect shape and we just haven't good places here to just make it "perfect". So, i can just buy new OEM crank or K1. HKS is really overpriced and have some issues with quality, so let's forget about it. So with which one should i go, OEM or K1 billet one ? Thanks.

Discuss ))

APM Racing

iTrader: (4)

I would go OEM. There is a local shop here that just broke a K1 crank.

Evo8luva

iTrader: (6)

Check out Manley's crank options.

AWD Motorsports

iTrader: (211)

I would suggest OEM.. at your HP goals youll be fine.. Not to mention we have NEVER broken a stock crank even at 1k HP..

Mike

StanRS

Thanks +++

well, it will take alot of time to ship it to Russia, according the fact that i'm pulling out my motor on next tuesday, it's not my choice, but thanks for the advice )

Very weightly opinion, according to the signature ) Thanks

ScorpionT

iTrader: (1)

For the power goals, you dont need more than OEM. However, I prefer how the lightened K1 performs. If you can comfortably afford one, go for it.

Ted B

iTrader: (6)

A word of advice when buying one of these Chinese-made billet crankshafts (e.g. K1, Manley, Eagle, etc.) is never install one right out of the box. Always have every journal checked for correct size, roundness, check the balance, and perform a Rockwell Hardness test at both ends. Yes, this will cost some money, but it's well spent. What I say comes not from speculation, but from real world observation.

FYI

evoixdk

Just wonder

Has anyone ever teted the OE evo9 cranck hardness in rockwell ?

94AWDcoupe

iTrader: (125)

I can give you a rough estimate as i have tested some similar. Factory cranks are very soft on the surface. less than 30c rockwell. most on this forum believe the factory crank is forged and superior to earlier versions of the 4g63 crank. These people are misinformed. Likely form mits using the words forged to describe the internals on the evo. The early 4g63 (6 bolt) crank is much harder on the surface. over 60c. This is due to those cranks having a .004 thick nitrided layer. Eagle, manley, K1 or any other crank made in china will come with a very hard crank surface as well. This hardness does two things for you. it makes the engine far more resilient to crank walk and spun bearings.

Many years ago now both WEB and Crower sent batches of camshfts out that were not nitrided Those cams wore down in less than 2000 miles use. i was around for all the threads that popped up with cam lobes wore down from the roller rocker. In short nitriding is very valuable surface hardness. In the case of cams its absolutely necessary for cam to live. In case of engine bearings its nice to have when starting engine (no oil pressure for 2-4 seconds) or when engine detonates. instant 4000psi cylinder pressure slams rod bearings onto crank. If crank is slippery it can live. Non nitrided cranks spin bearings quite easily.

Surface hardness has very little to do with crank strength. It is an eggshell like coating to it will make it stronger. But it is minimal to the overall strength from material used itself in manufacturing the crank. Cranks made in china are going to have breakage potential form the materials used. a factory crank has proven to be about unbreakable.

In short the best crank you can put in you engine is a factory crank that has been nitrided. i have been doing this for about eight years now.

rong.

iTrader: (10)

Where can somebody send a crank to get balanced, checked for roundness, and nitrided?

Teal2nnr

iTrader: (7)

^^ A machine shop..........preferably a reputable one.

Edit: the nitrated part i'm not sure, i know there is a company in Winnipeg that does all sorts of coatings, but that doesn't really help you at all.....for everything else machine shop