As in not sure what it does? Or why he's using it? What it does is aid in removing excess oil buildup on the crank as it slaps the oil pool and tacks onto the crank surfaces due to surface retention. The reduction in oil aids the affected rotational mass. Less rotational mass, the better. Why, cause all the cool kids use them. I plan on using the idea and making one for our l28 rally engine. Good in theory :br:
The teflon extension will have a running clearance of a fraction of a millimeter, so it "ALMOST" touches the crank. Plus, it's teflon, the slight swipes will be less detrimental than carrying a film of oil.
Did some work on the car. Pulled the harness from the motor prepping it for the motor pull. Also painted my TBs. Went with matte gunmetal and black springs to go with my textured gunmetal plenum. I'm also getting some Injen hardpipes and powdercoating them textured black. Repainting the cable cover as well. Currently waiting for the primer to cure. Dax, I'm gonna need another sticker, LOL And also got a few more parts for the rebuild. Brand new regulator, damper, o-rings for the fuel rail and injectors, new O2 sensors, and some Nissan Threebond silicone, some of the best there is. Not taking any chances of an old part failing on this motor.
You put forward a good question. The theory behind it suggests that the scraper will act as a knife edge. Removing the excess oil with minimal effort and affect. If you rotate a component quick enough in any given fluid. The fluid will continue to build in thickness (layering) on said component. Imagine the old practice of making a wax candle by dipping the wick then cooling, then dipping. Repeat it enough times it will continue to layer up. The same can be said for fluid retention, but instead of cooling we deal with continuous increase in rpm. Having this scraper will always assure minimal layering will occur. Truth is its probably only beneficial at higher rpm. But so be it. On this car its probably going to spend substantial amounts of time sitting on redline. I plan to use this concept for our new rally engine. Will be sitting pretty high on the rpm range, so I'm happy to custom build one.
To make it more user installation friendly, a laser cut full face stainless shim which locates via the bolts would be easier. But food for thought.
Pics of the crank scraper with the teflon extension installed. Instruction say that it is ok for the teflon to touch the ccrank and even some deflection is ok. The crank will bed into the teflon making the clearance it needs. Touchy touchy! Real close! Some more friendly touching action More clearance here since the counterweight has a slight step in it, so instructions say to clearance more so that nothing catches on the teflon. It needs to be a smooth scrape.
Edges of the teflon look a bit ragged and hacked up I thought they should be pretty much dead parallel with the the crank.
I thought they should be touching so the crank could wear in and create the ideal tolerance. Does anyone Teflon coat the crank? I wonder if there is a coating that will survive in that oily environment without being cooked
well, I don't have a surgeon's hands, so that's all my doing. You have to trim the teflon just so it touches. Extra clearance is needed in any areas where there are spots the teflon can catch, such as the drilled areas of the counterweight, and any sharp areas. No need to teflon coat it if you wpc treat it. It is a bit tough to cut it just right so that it touches everywhere, but I figure it is much better than no teflon.
It took me forever to pick what you had done to your throttle bodies. Why did you remove the front half of the arm that holds the butterfly? Is this for more flow or was it an accident?
I actually didn't do that. The guy who bored out my throttle bodies did. There is new hardware and a new throttle plate to match the 54mm bore it has now. I'm assuming he removed it since he doesn't see it necessary? In either case, the screws are either getting tack welded or getting some locktite to prevent them from coming loose.
I was thinking the same as Chrispy as I always thought the scraper kits were laser cut then hand pieced together. Hence giving you the close tolerances. Never understood before that 'you' the end user have to modify the kit to fit. The roughness of the Teflon sheet, just looked rough. But considering its diy'd. It's acceptable. I personally would clearance the Teflon to start with, rather then have the crank carve its way though. As the small worn particles will be floating around in your oil. Anyways, cool build. Keep at it!
