crystalbluevib said:
my block has been powder coated ( valley ) is that like an old school trick or do some engine builders still do this. I understand why it was done but im not sure if its still being done regularly. Do you guys know of any old school tricks you believe in , or would want to share? Patrick
Yeah, don't put paint on the oily side of the block. If it ever gets loose it will pack up on the pump inlet screen stopping the flow of oil. There was and is a school of thought that paint glued any loose casting sand or slag to the casting so it wouldn't circulate with the oil. Never mind that careful and through preparation and cleaning of the casting eliminates that potential problem. The other is that this activity speeds the return of oil to the crankcase. It certainly needs proving that gravity is insufficient to achieve this without help from paint.
Engines typically sit tail low so the busiest oil returns are those on the back of the block. For a wet sump engine, these need to be cleaned up with a die grinder and can be enlarged within structural reason. That doesn't mean ignore the front returns, but the rears will do most of the work. If your doing a small block Chevy, I recommend not blocking off the small drain holes along the cam as is so highly recommended. For a street engine this is a useless activity, your time and effort better spent elsewhere. For a competition engine that must also have a wet sump, I recommend the use of vent tubes in these holes which are available from the speed shop. This permits additional vent area from the crankcase and stops return oil from cascading on the mid crank area,,, AND,,, provides additional crankcase venting so that the returning oil on the front and rear block drains is not fighting the blowby vapors being vented up those same holes.
Also, do not use those lifter oil galley restrictor plugs. They don't work with a hydraulic lifter at all and for a solid lifter that runs with the factory ball and socket rocker, you need all the oil you can get to keep these things cool. The valve springs, also, depend on the oil coming from the lifter and push rod to cool them. So don't do things that choke upper end oiling, unless you really, really, really have first hand knowledge of how to lubricate and cool the stuff inside the rocker boxes.
In the pan is the place to worry about oil management. For a street driven engine that gets wound-up now and then but spends most of it's life at or near legal speeds, the factory pan is fine. A simple windage tray, a pump baffle, and a crank scraper will insure the oil is pulled off the crank, put into the pan, has a chance to de-aerate, and stays around the pick-up when you get on it. If the engine is going to see some serious racing then you need to add a pan with baffles and trap doors, and do some additional work to the windage tray, I like louvers, lots of louvers, they are aimed at the approaching crank which when viewed, they face up at the crank with the open end toward the drivers side of the block. Here you can go for more capacity, down if there's space, an inverted T for the street and road course engines, an inverted L with the kick out on the passenger side for circle track cars going left all the time.
I do not like forcing all the oil through the filter all the time, or at least creating a situation that could cause that when the engine is needed more oil than the filter can supply. So I never recommend disabling the filter by-pass valve. The failure of the filtration system to meet the engine's demand for oil will result in a blown engine, not just some scratched bearings because a piece of carbon got by the filter. As far as protection from chunks of metal getting into the oil, this most often comes from the cam drive and the heads. From the cam drive the best thing is to avoid roller thrust bearings and just use a simple thrust washer. For the heads, it's roller trunnions on the rockers that usually come apart. The use of screens in the oil returns and cow stomach magnets are your best hope of stopping this junk.
I really like Melling's oil pump with the bolt on pickup for the Chevy rather than welded or pressed pickups. My preference is the Melling 10552 or 10555 with 10% or 25% greater capacity respectivly
Bogie