Yeah, the whole idea is to slow the oil flow from the pan, the work great and don't cause any ill effects at all.

The problem with an automotive engine in a boat is simple, the automotive engine runs at say 3000RPM most of its life, but at part throttle, would run vertually forever, whereas the boat engine, when running at speed is at 90% throttle and 4500-5000 RPM, this will move a lot of oil, the Olds engine has a horrible oil return system, small holes, many crevices, horrible windage control etc.


The oil restrictors limit how much volume can be pushed "upstairs" reducing the amount of oil needing to be returned to the pan, if you think about it, the returning oil has to fight the engines blowby to get back to the pan causing severe windage, foaming the oil, foamy oil does not pump, the pump cavitates and your done boating for the summer......


We have had a few 455's and the all ran very well, the last one made a bunch of power and ran right to 5000 RPM and maintained 60 PSI oil pressure without fluctuation, it had the restrictors.

A big pan and a windage tray are neccissary also, (crank scraper not so much) also a good evac system seems to help a lot.

It also helps to open up all of the oil return holes and Glyptol the rough surfaces.....


Do it once, do it right.....

GT

Hmmm, I will have to research that a little.  I am using Amsoil 10/40 synthetic which does not foam so maybe that will help too.  How does the 455 oil the top end?

Just like a 454 Chev. but with a lot more oil....through the pushrods, they are messy as hell w/o the valvecovers...Remember, your not blocking the oil, just slowing the oil down a little, BTW Amsoil is the schizzle, been selling it for 15 years....and yes it will help..

GT

damn GT you know your sh*t!! high flow oil pumps are not a good idea?   

If you have blown up as much stuff as my buddies and me, you would have a bunch of "what not to do's" also

My dad owned and operated an automotive parts store and full machine shop for 30 years, I've seen it all as far as old school, my uncle (dads brother) was his machinist for 20 of those 30 and we all had boats (mostly jets).

They're not needed IMO, everything on the Olds is so big, I don't think a high volume pump is a good idea, high pressure maybe (just a different bypass spring) especially with the restrictors (high pressure does not change the flow rates). I would think a HV oil pump could run the risk of bearing wash...?....

Does anyone on here remember the external oil bypass for doing the same thing but externally? There was a Olds freak making a kit that took oil from the front of the engine and went to a three way valve to a regulator that put oil back into the pan and kept Cam oil under control with a set pressure, I'm getting tired and can't remember shiat.

GT

Tom -- I love it when you talk like that 












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