Crankshaft - Re Grinds

red reading

Active Member
After many wrong information for people regarding cranks and re grinds the facts listed below are exactly that...facts.

cranks as standard are gas nitrided .

no cranks have ever snapped in the gtir engine,

cranks can be reground down to .75mm undersized journals,

nissan spec for standard main and big end undersized shells are .10mm,.25mm and .50mm.

the .75 mm is available from acl bearings,

you can get a crank re gas nitrided if need from most good machine shops,


to put this into perspective if your crank can be reground to the sizes above it can be used, there has been no evidence of any cranks snapping or of cracks appearing on journals and stock gtir cranks are used in 1000bhp applications with no issues, also other sr20 cranks will fit the gtir engine but they do have smaller flywheel bolts, you can have small sleeves made up to be able to fit a gtir flywheels to them though. And another point to cover is the gtir conrods and bearings are 19mm and other sr20 are 17mm wide, the gtir conrods will fit the other sr20 engines with no modification as many in the drift world have been using gtir conrods in the 200sx sr20 engines.
 

red reading

Active Member
Not a problem, the next crank info I will be doing will be the differences between the stroker kits especially rods and piston sizes.
 

stevepudney

GTiROC CHAIRMAN
Staff member
Good article Dan.

Could we have one on the various strengthening treatments available for cranks (and any other engine/gearbox internal components etc.) . What are the different heat treating procedures, and how effective are they, nitriding, WPC, Cryo etc. and are they in your opinion worthwhile.


Steve


 

red reading

Active Member
I will when I have time, there are so many to do though, from cryo,shot peen, heat treatments, to micro polishing,I will also ask that it is marked so other sites cannot copy it as my nme info was put up elsewhere with out my permission......only half of it but still personal information from the drivers setups.
 
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