K5.9 Engine installation

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Hunter90 HD

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15
Hi All,

I have brought a K5.9 engine and I was wondering if this would be suitable for a Savage 4.6 replacement, I am concerned the power would shred the differentials?

Would I need to upgrade the differentials on the standard setup Savage 4.6?

Any tips?

Cheers
 
You could run it and replace as needed. Is your current the X or non-X version? The older pre-X had a weaker gear box that would flex under load. Diffs didn't last long in that with higher power engines. When I had that version, I ran alloy gear boxes. With the X+ versions, they made the gear box more rigid and you can pull the diff without taking the entire front or rear off the truck and disassembling the bulkheads as well.

Even with the X and machined steel ring gear (vs sintered), they still don't hold up as well as the sintered BP ring/machined pinion. The alloy cups help with wear as well over time.
 
You could run it and replace as needed. Is your current the X or non-X version? The older pre-X had a weaker gear box that would flex under load. Diffs didn't last long in that with higher power engines. When I had that version, I ran alloy gear boxes. With the X+ versions, they made the gear box more rigid and you can pull the diff without taking the entire front or rear off the truck and disassembling the bulkheads as well.

Even with the X and machined steel ring gear (vs sintered), they still don't hold up as well as the sintered BP ring/machined pinion. The alloy cups help with wear as well over time.
I have both versions I have like 5 savages in total :), but I do have a Savage X.

On the 25 version it is a real effort to get to the diffs, like you said. I think installing alloy gearboxes I will do that’s a good idea.

So upgrade Savage X install alloy gearbox and alloy cups.

How about the pinion hear how does that hold up do I need to upgrade to a metal pinion?

And also, the centre differential, will that hold up? Is there any recommend upgrades?
 
The X and later don't need alloy gearboxes, just the cup. When you do get the alloy gearboxes for the pre-x, make sure to get 12x16mm shims as you will need them to get proper mesh.

The pinions are all machined steel, be it the BP or standard pinion. There are both sintered and machined steel ring gears for both standard and BP diffs. I have found that the sintered BP ring gears hold up fine to nitro. If you had a flux, then perhaps machined BP would be best.

The savage line doesn't come with a center diff. You can get a center diff trans for the standard flux and XL, or an aftermarket center diff mount for the flux/xl. I suppose you could do the same for nitro, at the very least the transmissions with a center diff, but they are single speed (no shifting).

I just run a standard 2 speed trans in my X with BP sintered diffs/alloy cups and an LRP30. In my FluxHP (standard length), I run a super 5SC transmission which has a center diff in it and machined BP diffs with alloy cups.

I do run steel spurs on both. On the nitro, when I geared taller than 49/16, the slipper would slip and melt the spur, so I got the steel spur for it and haven't had an issue since.
 

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