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Marko, dont mind if I answer your question do you?

Nitriding is competely different to cryogenic freezing. Nitriding is a process where a component has nitrogen introduced into the metal surface (under high temps). Makes the surface super hard but you still retain the metallurgical properties of the orginal metal beneath the nitrided surface.

awaits splined collars + gears. preferably to fit standard GTR pumps since it's imo a waste of money buying an N1 to rip out the gears anyway.

Yeh that's something greg said the other day aswell. A std pump will be more than capable to supply enough oil at the right pressure.

that's a bit worrying.

splines are the best option imo without opting for a dry sump. using a splined system you can use a material that does not have to be as tough as the OEM system (which is very very tough but also brittle).

Ideal gears will have the plastic deformation limit quite far from the UTS. As obviously the closer the plastic limit to the UTS the more brittle it is. Personally id rather the gears round themself off than sheer in to pieces.

what material are these splines/gears going to be made off?

4140 as per below :)

Apparently.. "The collar will be made from 4340 and the gears made from 4140. Both will be nitrided and isotropically treated."

Getting all in 4140 so we can wire-cut the splines out of 1 piece.

Nitriding will penetrate the surface between 4-6thou, so it wont affect the structural strength or make them 'brittle'.

Shane,

Have you had any issues with machined parts moving after you get them nitrided?

PS: wire cutting is f**king sick!!!!!

I cant say i have mate, but these will get a final surface grind after they are treated and a double check before i'm happy to say they're good to go.

It certainly is! :)

I cant say i have mate, but these will get a final surface grind after they are treated and a double check before i'm happy to say they're good to go.

FYI: I've had a few issues with some things moving post nitriding. Final grind post treatment is the go! :) (just dont break through the lovely super hard surface).

Generally things must be surface ground after nitriding due to the surface expanding unevenly. That is the gas can be absorbed at different rates in the material. However given that these are gears and not a bearing surface (like a crank) it should not matter as much.

Cryogenic treatment is excellent in making material stronger. So you have a good mix. Nitriding does nothing for strength but makes the surface very tough and cryogenics does nothing for toughness but adds strength (re-aligns the grains correctly i believe)

potentially Allows obviously a more plyable material to be used which IMO is a good thing when it comes to gears.

GTR standard pumps would be the go imo! Looking forward to these, hopefully a cheaper cure to this problem.

PS: How many splines are there going to be (sorry if this was mentioned earlier also) As obviously the more splines (think 10 splines per 25mm) the larger the surface area but with that comes smaller splines which requires smaller tolerances which may not be suited for the heat expansion that these gears will come under during the operation of an engine. Looking at the Supra design posted earlier in this thread would be a good way to go, not very many splines but it's clearly a tried and proven logic.

PS: If possible 4340 is the superior material compared to 4140 but obviously it does come down to the manufacturing processes s available.

Edited by GT-RZ

Excellent thread this one!

Gotta be one of the best ones in a long time, a problem came up and with the bouncing around of ideas, a possible but more then likely probable solution has been achieved and not only that, its actually going ahead rather then just talk.

Kudos to Greg, Shane and everyone else who chipped in.

Need more informative and potential RB development threads like this rather then same old same old.

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