|09-18-2007 03:49 PM|
|09-18-2007 11:59 AM|
HMMMMMMM........................................Mo roso 22010 • Reduces oil flow to upper engine assembly, leaving more oil available for the rod and main bearings
• Reduces power-robbing windage by reducing the volume of oil passing by the rotating assembly on its return to the pan
• Do not use with hydraulic lifters
When roller rocker arms are installed, along with a mechanical lifter cam, the amount of oil flow required to the valvetrain is greatly reduced. Installing a Moroso oil restrictor kit will limit this unnecessary oil flow. These kits reduce the power-robbing windage created from the excess oil draining past the rotating assembly and keeps the oil flowing where it is needed most, the rod and main bearings.
|09-18-2007 11:30 AM|
Aside: With modern active technology the wetsump could easily have comparable lateral limits to the dry sump. Of course, it would likely be as expensive. Also, such sumps would be promptly ruled illegal in various racing classes.
I had to chuckle when I suggested deepening the pickup in the BF/B6 Mazda engine. Nothing to gain there but keeping the pickup covered under higher angles of repose. Engines are expensive and it is silly to blow them up needlessly. Specifically addressed as illegal in the next set of regs to come out of the SCCA in 2006. In 2007, no mods at all were allowed unless specifically mentioned -- easy way to address it. But any oil can be used.
|09-18-2007 10:08 AM|
|Rick WI||Wet sumps by design will always have lateral oil control design limitations simply because they are wet sump. Design features separate from the windage tray are incorporated into the pan to minimize this issue, baffles, trap doors, pickup location and so forth.|
|09-18-2007 09:38 AM|
The functions for a good windage tray, when examined in detail, have conflicting tasks.
Wet sump pans with windage trays etc. usually have lateral acceleration design limits. Dry sumps then enter the picture but high end dry sumps also typically employ windage trays.
|09-18-2007 07:56 AM|
Oil restrictors are NOT recommended for use with roller cams.
|09-17-2007 11:32 PM|
Per Canton website, nice and simple as most things are.
Windage is the flow of air within the crankcase. Each time a piston comes down in the piston bore the air under it is pushed into the crank area and each time the piston goes up the air is pulled in behind it. In a eight cylinder engine all eight pistons go up and down each revolution. At the same time the rotating assembly is spinning and churning the air. Oil coming off of the crank is also put into the mix. So as the RPM increases so does windage. At 6000 RPM’s the assembly is rotating 100 times a second.
A windage tray keeps the windage around the crank from the oil in the sump area. It should allow the oil coming off the crank to easily enter the sump without the windage affecting the oil already in the sump. A good windage tray should also keep the oil in the sump from getting into the rotating assembly when the action of the vehicle is in motion.
Basically nothing more and nothing less.
|09-17-2007 11:08 PM|
|09-17-2007 09:59 PM|
|firstname.lastname@example.org||Also realize that MUCH of what they write in rod magazines is blatantly incorrect. You have to do the leg work necessary to educate yourself about the facts. DON'T rely on ANYTHING the rod magazines say.|
|09-17-2007 12:35 PM|
|BBCMudbogger||Then when you get into solid roller oil restrictors will probably become necessary.|
|09-17-2007 05:52 AM|
|baddbob||A deep sump pan and crank scraper work well. I've also ran a scraper and windage tray without any problems. But on the last motor I built with a fairly aggressive solid lifter cam I put it together without any scraper and tray-just to add some extra oil being thrown at the cam. I've also added vent holes above the cam where the factory didn't have any just to get some more drip on the other lobes. Lubrication on these flat tappet lobes is getting to be tough subject with the junk oils now on the shelf. My next BBC build will have a solid roller cam.|
|09-17-2007 05:09 AM|
I read a lot of forums and have felt bad over how some reputable cam manufacturers had their names dragged though the mud by people who didn't realize the reformulation had taken place.
|09-16-2007 06:57 PM|
|GCD1962||My 70 LT-1 Short Block came stock with a windage tray. I also use a lifter valley baffle to keep hot oil off the bottom of the intake. Windage trays have proved their benefit for nearly 40 years in performance engine. It seems that maybe Crane is trying to cover "all the bases" for the poor cam blanks and lifters that are resulting in cam lobes being wiped out during break in. The LT-1 short block has been in my '62 Vette since 1973 and I have had zero problems. I had the heads and pan off last year while doing a frame replacement and the inside of the engine, including cam and lifters are still perfect after all the years.|
|09-16-2007 09:59 AM|
|09-16-2007 02:54 AM|
re windage trays
Edit: For some reason my new posts to the thread do not seem to be showing up. Yes, Crane states this -- I checked before posting. It is under 1. A) at cranecams.com/?show=faq&id=1
A constructive solution might be to add the often seen OEM oil ejector slots on rod faces that are aimed at the thrust surfaces of the piston bores. The oil ejected from these slots would include the cam in their upper quadrant sweep. This is an extremely simple mod to do.
Windage control devices help keep the oil running cooler and in a way that dedicated oil coolers do not. This is certainly critical in cooling the camshaft efficiently.
Once the energy from the rotating assembly is transferred to the oil by hitting it or moving it the oil rises in temp. That is energy that is lost forever to make your engine perform better. It is also allowing the exact opposite of the dual (lubrication/cooling) function of oil.
Windage trays are meant to prevent this sort of parasitic loss from oil splashing onto the crank and to shield the sump oil from windage effects. Many trays have scraper louvers built into them that strip away oil from the windage cloud. The louvers also help disrupt the pressure differential that forms around the spinning crank (the differential allows the windage cloud to form). Disrupting the pressure differential allows more oil -- not less -- to be directly and immediately ejected in the upper two quadrants where the SBC camshaft sits -- thereby cooling and lubricating it. This oil would otherwise be drawn into the cloud. The windage tray operates in the lower two quadrants of crank rotation. The windage cloud is self-renewing from oil ejected from the mains, rods and draining down from the lifter valley and heads.
It is a common misperception that a windage cloud will not form because of a windage tray and that a windage cloud comes primarily from splashing oil in the sump. The latter might be true during abrupt manuevers but during steady driving a windage cloud will form with or without a tray in place. It will increase in oil entrainment as a function of rpm because of the higher pressure differential formed. To increase oil entrainment volume it will simply capture a larger amount of ejected and draining oil before reaching equilibrium.
Once the oil has absorbed heat from the camshaft and lifter it needs to be removed as quickly and efficiently as possible so that new, fresh -- and cooler -- oil can take its place. Just like the water cooling system in a car -- circulation is needed.
If still additional oil flow is needed to cool the lobes or lifters then dedicated passages or devices need to be devised to do so. This is just like using oil to cool the underside of pistons in turbo or highly tuned NA engines. In those applications windage trays are typically seen more often rather than subtracted as the tech tip logic would dictate.
Windage control helps keep sump oil temps down as mentioned in the beginning but running a dedicated oil cooler will help keep oil that is moving through the galleys -- then to the cam and lifters -- cooler. An oil cooler, though, cannot give back the energy lost when it rejects it to the atmosphere -- as windage control devices can by preventing the energy loss/transference in the first place. Both cooling approaches are valuable.
Also the "do not use a windage tray" advice contraindicates any sort of dry sump system as it removes much more oil from the crankcase and more quickly as well. Think about it.
I think the cams are clearly pushing the limits of the materials and design of the components and many plausible sounding things are being thrown out in an effort to lengthen that life. This advice, though, appears to be a step backwards.
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