Yes.
As long as it is for someone who has sense enough to change the filter once in a while
Dirty oil is a wee bit better than no oil at all

 

I blocked mine but I don't drive it in cold weather and I let it warm up for a long time before I go over 1500 rpms. You don't want to collapse your oil filter. Run the best filter you can get.

 

I avoid plugging them...

The filter bypass is a differential bypass. So it does not bypass oil unless there is a predetermined differential of pressure between the gallery and the filter.

So if motor is running 50 psi pressure, the filter outlet side may have to drop to 38 psi before it starts to bypass. Seems it is around 12-18 psi differential usually IIRC.

I'd rather have some oil than none at all as Wolfplace mentioned and plugging it eliminates the possibility of not only dirty oil but any oil at all if something weird happens. Like an internally collapsed filter media..

 

TTT

 

I run a blocked bypass on the street with no problems. However I run the large WIX filter and 10-30 oil with the stock pressure spring in the pump. Have had zero issues with the bypass blocked.

 

I block the bypass. One shot of dirt in the bearings is more than I want. If one is contemplating blocking the bypass, you must also contemplate using good oil and a good filter, changing the oil regularly, and acting like you have blocked the bypass. Let the engine warm up thoroughly before you create high oil flow conditions.

 

Every race motor I ever built had the filter bypass plugged. Every street motor I ever had had it operating the way the factory made it. In one of Jenkins books he states that even a smallblock requires the 2quart truck filter to flow enough oil at high RPM with the bypass plugged. I don't know of many street cars that have room for the big filter. It is just too easy to get into trouble with the bypass plugged.

 

Originally posted by Mike Feudo:
Every race motor I ever built had the filter bypass plugged. Every street motor I ever had had it operating the way the factory made it. In one of Jenkins books he states that even a smallblock requires the 2quart truck filter to flow enough oil at high RPM with the bypass plugged. I don't know of many street cars that have room for the big filter. It is just too easy to get into trouble with the bypass plugged.

-
So Mike,,, are you saying all your street engines were hi RPM & all your race engines were low RPM??
By your above description, I would think you would want to have a bypass on the race engine & not of the street engine unless you always run huge filters on all your race stuff...

I have been pluggin them in most performance stuff I have done for more years than I can remember & have never had an issue.
But as Jake noted above, it probably isn't necessary,, and there are some people I wouldn't even consider doing it for

 

Originally posted by onovakind67:
I block the bypass. One shot of dirt in the bearings is more than I want. If one is contemplating blocking the bypass, you must also contemplate using good oil and a good filter, changing the oil regularly, and acting like you have blocked the bypass. Let the engine warm up thoroughly before you create high oil flow conditions.

This advice (and that of others that echo it) is all you need to know. I, too, have a blocked bypass and I use 5W-30 or 0W-30 synthetic oil and PF35L filters (they have synthetic filtering media, which works better with a blocked bypass). I always drive very gently until I see my oil pressure at the operating level at idle. There are other good oil filters out there, too. Do a search to find some of them.

 

I have been using the Fram HP4 racing filter and a blocked bypass. What's the opinion on the HP4? Can you suggest a better alternative?

Troy.

 

Originally posted by Troy70SS:
I have been using the Fram HP4 racing filter and a blocked bypass. What's the opinion on the HP4? Can you suggest a better alternative?

Troy.

K&N's with the big 1" nut on the bottom. Good filtering, high, high burst rating.

 

Originally posted by Mike Feudo:
Every race motor I ever built had the filter bypass plugged. Every street motor I ever had had it operating the way the factory made it. In one of Jenkins books he states that even a smallblock requires the 2quart truck filter to flow enough oil at high RPM with the bypass plugged. I don't know of many street cars that have room for the big filter. It is just too easy to get into trouble with the bypass plugged.

With What oil? 20w-50?

I use 5w-30 Mobil 1, and i consider it to be about as "thick" as i would want in my motor.
Plugged Bypass, Wix "Racing" Filter, or K&N.

I chance the oil in my street/strip car about every 1500 miles.

I dont womp the throttle with cold oil ethier.

 

We ran straight 40wt racing oil. All of the race motors used the 2qt truck filter. With 40wt oil we had to be real carefull about warming the motor when it was cold outside. There are lots of real good reasons to block the bypass. Twice we had total cam failures. normally it's a complete lower end rebuild but with the bypass plugged all that was hurt was the pump. The filter caught everything from there on. On a street driven car I believe the possible bad things outweigh the good things. If for any reason you can't get enough flow through the filter it has the same effect as running out of oil. Most street engines don't have anywhere near the maintance that a race only setup does.

 

http://www.scuderiaciriani.com/rx7/oil_filter_study/

 

Had a rebuilt 427 with blocked bypass that colapsed the AC/Delco oil filter on the second easy run around the block (cam was properly broken in). Runied the motor, required complete rebuild, Very disapointing.

 

I wonder how a filter goes from working well to collapsed in one trip around the block? Was it a fresh filter? One mistake made by many is to assume that the break-in filter will last for 500 miles. This is when all the moly lube, white grease, red stuff, lint, etc comes around and gets into the filter. I monitor the oil pressure religiously during break-in and change the oil filter if it starts falling off. Once the engine is broken in, you should not have any problems. We have run almost 2000 hard miles in the road racer over a period of 6 days with the same oil and filter and had no oiling problems at all.

 

my break-in filter went in the trash 40 minutes after starting it, and the one after in about an hour of driving.

 

Straight weight, and heavy weight oils are very old school in a Gas engine.

Pro Stockers use oil thats on par with the consistancy of alcohol.
Which isnt good for a street car, as the consumption rate will be high, but neither is 20w-50 or straight 50 or 40. Its a long ride to the top end of a motor when its cold out with oil that thick.

i dont use cheap filters ethier.

 

Pro Stockers are looking for the last ounce of horse power. Longevity is of little concern. If you want an engine that is pounded hard to live use oil that will stand the pounding.

 

Really?

The bearings in a Pro Stock motor go the entire season without being replaced.

super heavy oil makes for LESS protection, not more.

 

"Speedy Goomba wrote:
Darin,
We've had the same results as you with mine and my fellow racer's testing. Our engines are quicker and faster the colder that are ran out. My ET's will fall off if i'm hotlapping.

We tune for 140 degrees as thats typically where we run them at (bracket racing).

My friends in stock eliminator run their cars ice cold to make a fast pass, but this is accompanied with double zero weight oil.

my question, what are you guys using for gear oil in the rear?
i'm currently using 75w-90 synthetic gear oil (mines street driven as well as raced)


We have tried some of the 40w Synthetics in the rear end and burned them up. We are back to the 75W. Our engine oil that we use in the Pro Stock engines is 005W. It like pouring alcohol in the engine. Its so thin it still shocks me that it can set up a proper hydrodynamic wedge in the bearing and carry the loads we put on them but it does. The additive packages in these oils are so complex its amazing. They have just the right balance of phosphorus and molybdenum and other assorted chemicals I am not aware of. One little tiny mistake in the formulation and they wont make power. These new Synthetics are a Mad scientist paradise. When they work they really work! Did you know that we can run our main bearings ALL YEAR! We never replace them unless there damaged and that almost never happens. We run .004 on the mains and .00375 on the rods and .002 on the wrist pins. If you tighten anything up more than that at the temps we run these things, you will fry the bearings. Someone here asked what piston to wall clearance we run. That depends on the piston design and manufacture. We use or should I say, test every manufactures piston. They all take different piston to wall clearances due to there design and metallurgy. We run CP pistons the tightest at about .007 and they seem to run the best so far. " - Darin Morgan R&D cylinder head department, Reher Morrison

 

back on topic, I'm not talking about using super thin oils, but really just taking a Tip from the professional Class racers and realising that SUPER HEAVY weight oil is Old school and offers no protection for the engine.

It wont flow when its cold!!! Then you need to put alot of heat into the engine to get the oil to flow, which then kills the power by heating the intake change and detonating becuase of excessive heat.