I have a interest in plugging the oil bypass valve and force all the circulating oil to go thru the filter. In doing so i will install the wix filter that is for racing and flows at a much higher rate. I get this idea since I run a 20-50 oil because my mains are just a tad oversize but not so over that I need to go to the work to correct the clearance.

Any body do this or am I just wasting my time and energy. I kinda like the idea of all the oil passing thru the filter.

 

Not a good idea.

The bypass valve is there for a reason: so you don't loose oil pressure as your filter gets filled and in case of media collapse.

 

Done it for years. If something goes bad at least it tries to catch it all. Most folks around here change oil and filter regularly so not an issue with plugged filters.

JIM

 

I have a bypass installed as well. Seems most engine builders recommend it.

 

If you have a filter problem/defect which limits oil flow through the filter and you DO NOT have a bypass, you will blow out the filter and dump oil. I can't believe racing rules wouldn't require a bypass on the engine or in the filter.

 

On Chevys, there is also a bypass in the oil pump. Once the pump reaches its designed pressure, the bypass opens and dumps oil, which maintains the pressure high set. This bypass is also the mechanism one uses to adjust the bypass pressure (stiffer/lighter spring or shims), which obviously affects system pressure.

The filter bypass only directs flow through the filter and has nothing to do with system pressure. They way they generally work is though an imbalance from the inlet to the outlet. It usually is around 5-10psi difference for the valve to bypass the filter. A stuck valve or a bypass block will generally not blow the filter off the block unless you are running the system pressure well above the filter's pressure capacity. So, 80psi of oil pressure is still going to hit the filter whether you bypass or not.

 

The pump bypass should keep the system from breaking anything.

On a street car I do not see the benefit of blocking the bypass. Race engines do it to force all the oil through the filter since they are working much harder constantly and that extra little bit of clean oil is more important. However, race engines change oil much more often and do routine checks to make sure everything is in good shape before each event. You may not know if your street engine has a problem right away.

Also, the use of thicker oil just puts more stress on the pump. Just because your mains have a little extra clearance doesn't mean all the ports the oil flows have the same amount. It is just a band aid fix, and so would blocking the bypass. The proper solution is to fix the bearing clearance and run the correct oil. Almost all bearing companies make under/over size bearings. You should be able to find something to fit your measurements. As long as the crank journals are in good shape you shouldn't need to pull the engine and do a full rebuild.

 

There is a benefit, but like most things we deal with when working on our cars to "make them better", there's also a down side.

While it's not hard to find the information for one's self, only a small fraction of your engine's oil actually passes through the filter. Most of it is bypassed. This kind of tells you that if your daily driver engine has a 200k+-mile life expectancy, then maybe it's not really necessary for every drop of oil to pass through a filter all the time. A bit at a time seems to get the job done.

The down side on a street engine? If you do a block of the bypass, your chances of doing great harm to the engine increase dramatically. There are a lot of very small particles suspended in the oil that will do no real harm to the engine but are just large enough for the filter to catch. If you block the bypass and the filter clogs, then little to no oil will go to the engine. It's just a general recommendation, but it's best to replace the paper canister filter with a plate or cylinder screen filter that also uses a tattletale. Oberg makes a very good filter for this in the plate style. System1 for the canister type. You will be cleaning the screen quite often. It's rather impractical to continue to use a paper filter unless you own stock in Wix. You also can't easily tell how much junk is going into a paper filter.

 

If it gets cold it's a bad idea with thicker oil, but if it's only warm weather use I do it on my cars(or change to a thinner oil if I know I'll fire it up in winter) to make sure I get 100% of the junk, still make sure the engine is nice and warmed up. I also change my oil more than others and use a larger filter(more surface area = less restriction). Plus I use Filtermag, I figure it should plug the filter less and flow better longer.

You could also consider an oil heater.

 

Thanks to all for the input,,,,I will purchase a filter mag ( good idea ) and the tool that cuts open the filter for inspection(s). To me this car is a summer sport only and I don't get out in it when temps are below 70,,,I'm the same way with my motorcycle I guess old age has set in LOL.

With the chance, as has been mentioned, the filter getting plugged and restricting oil to the engine,,,,wouldn't that start to show up on the oil pressure gauge with readings lower than my normal pressure for my particular engine? I doubt the filter would plug up all at once but more in a gradual manner giving me a chance to change the filter.

BTW The aviator pic is me at the age of 18 sitting in the 69 pace car along the pit lane the day before the race. I was able to persuade the driver to let me in the car for a pic. About 2 weeks after the race the car had a electrical problem and burned up,,it was supposed to be given to the winner of the race Mario Andretti.

 

If you need to "crutch" a low oil pressure problem, use a thick, wide range multi viscosity oil, like you are. I like mobil 1 15W 50, or there are others too.. Then no need to remove the bypass.

 

Most oil filters also have a bypass relief. You can research the specs on the various bypass pressures and pick one that is high then block off the engine's bypass knowing that if the worst happens you will still have oil pressure.
For a racing type filter with high flow and high strength check out the Fram HP4 page 10 on this document. 22psi for bypass. Keep in mind that is relative pressure not your oil pumps pressure output.

http://www.fram.com/media/7069/fram_...duct_specs.pdf

 

I would much rather my engine get unfiltered oil than no oil. My understanding is without the filter bypass, the pressure will climb until the pump bypass starts bleeding off excess as less and less gets through to the bearings and lifters. You could "fix" that by also plugging the pump pressure bypass. Then you'll blow the filter off or (not sure if this is a chevy weak point or not) pretzel the pump drive shaft if you have a filter clog.

The old flat heads only filtered about 20% of the oil. The oil in the sump has already been through the filter hundereds of time. If something is putting so much trash in the oil that not being fully filtered for a few minutes before it warms enough to all go through the filter is an issue, you have MUCH bigger problems, and the engine is already trashed.

 

Plug the bypass and run a high flow filter such as the Wix or the Fram HP4....
Been doing it for 25 years with zero issues and will do it for 25 more.....

Jebby

 

I don't agree with opinion. all my performance motors are non bypass.

I use WIX and K&N high pressure filters and limit my pressure to about 65 hot by changing the oil weight to seasonal temp changes

 

Plugged my bypass when I rebuilt it. Previous owner apparently rattled the the hyper piston causing the a piece to break off from piston skirt. All those little pieces may have been pumped through the engine, damaged the crank and all bearings. With metal in the oil your going to damage your engine either way, restricting flow through filter or pumping metal into your bearings. Take your pick.

 

I always replace the bypass with a billet filter mount (Canton) now after I had a cast OEM one crack on me one time. I had a CE replacement LT-1 motor that had a factory blocked bypass filter mount, used to have it kicking around in my spare parts, I don't know it they were ever on any OEM motors.