With that level of engine modification, I think that Kubota would declare the engine warranty to be void.
It is a figure of speech. The point being that I went through 3 units and finally found my huckleberry. The 3560 just checks all of the boxes for my use case and the LA805 loader is a big part of it. Heck, I didn't even even modify the loader relief valve pressure on this thing. She is doing what I ask of her just the way they put her together. It is a nice machine to have around.
You can dang near see light under those rears.
Kubota is extremely touchy about any and all modifications to the drivetrain and engine, but then all brands are. Why buy a diminutive unit in the first place. Buy a unit that fits your needs and don't modify it at all. Never understood that philosophy at all. That of course applies to all brands.
The L2501 Turbo kit is expected to run just under $3K, which gives you a savings of roughly $2K on an L3901 and $4K on an L3902.
We modify because we don’t want to deal with complex and complicated electronic engine controls and emissions equipment. We modify something so we don’t have to buy more tractor than we need.
Most parts can be ordered from the dealer. No tractor mfg makes their own oil so as long as the oil and fluids meet minimum specs called out in the owners manual it won't matter where you buy the fluids.
You're not alone. And I don't fault anyone for buying more tractor than they need. There are situations where an individual doesn't want, or need more tractor and the Turbo kit is an alternative for those folks, especially when they don't want to deal with emissions or purchasing an older tractor without emissions equipment. Heck, and most of those 'larger' tractors are turbocharged too!