| what bearing to use as I only have my own experience to go by. What I can say is this: Nissan spent a chunk on R&D of this vehicle and like so many other over-engineered components in the Z32 I think the bearings qualify as one of the biggest. Nissan developed a material called kelmet (sp?) which is a lead-copper alloy/mixture made specifically for this engine... I've seen machine shops with hundreds of thousands of dollars of machinery and tens of years of experience build VG's with non-OEM bearings and have seen percentagewise more rod bearing failures shortly after. On the other hand, I've built a handfull of VG's using OEM bearings and $.99 stick of plastiguage and everyone of them get beaten on daily and have tens of thousands of miles without any issuses. Even my own car and the way I spin the sh** out of my engine, on each breakdown of the engine the bearings have been TITS. Although I didn't do this, I would have been content to just put the used bearings back in. That 'gut feeling' told me otherwise, of course.. I've heard of some guys building VG30DETT's with z31 rod bearings because they are harder. I have uncertainties that going with a harder bearing is actually better. During high load or even detonation, a harder bearing is going to drive into the journals and have higher probability of galding the surface of the crank journal. Once this occurs, the bearing is history. A softer bearing not only will lower this chance of galding, but it will also endure significantly more fatigue before breaking apart. I've never used clevite bearings before but I would assume thay they are using a material that is used in a large number of different bearings they supply for different engines. While it may be the material of choice for one engine, it may not be the right mix of properties for another. My gut feeling tells me that a 'one size fits all' approach to designing anything will leave a lot to be desired in every application. Only by specifically designing a component for a system will it be the best that can be had. With that in mind, I'd be willing to bet that Clevite never put the bearings in a VG30DETT themselves to see how it behaves. They simply produce the bearings with specific geometries based on the Nissan OEM size. I'd also be willing to bet that they are not offered in the various grades like Nissan does it just so you can get things that much better matched. In the end, I like Breyers Mint Chocolate Chip Ice Cream. I know that if I go to the store and buy a gallon of it, I can go home and enjoy what I know works for me. Its just by my experience that I do what I do...
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08:32:27 09/06/03
