Oil modifications

[Don Coatney]

Thanks for posting the above information. It appears David Pollock has spent some time with these engines. I understand and agree with most of what he says about modifying these engines to increase horsepower and RPM's. I do not agree with his statment "With a greater volume of oil coming from the larger grooves in the main bearing shells you can plug the squirt holes in the rods. This little hole tends to deflate the oil cushion around the bearing, especially during the power stroke. With the added oiling there will be plenty of throw-off for cylinder walls". I am not an advocate of increasing the grove size in the bearings and I dont think the rotating crankshaft splash system will do a good job of cam lobe lubrication espically at lower RPM's. I think a greater benefit would be cross drilling the crankshaft for increased oil flow (as I mentioned in an earlier posting) and leaving the squirt holes as is. I am surprised that Pollock did not mentin that in his write up.

 

I am curious about the rods you found with no squirt holes. Where did you find them and are you sure they are for a Mopar flathead? What are the plans for this engine you have? Will it be street driven or is it strictly a race vehicle? I have a couple of friends who routenly run there engines in excess of 5 grand. To do this they have done many of the modifications that Pollock mentioned. One guy (George Asche) lives in Venus, PA. He does not do the interweb but he will talk your ears off if you call him. His number can be found in the links section of this webpage.

 

In reading the Pollock information I dont believe he ever stated that the factory oiling system was weak for daily service. But he is an advocate of increased oiling for pushing an engine above its design levels and I can understand that.

[Clearfieldsgarage]

This is going to be a street strip vehicle and I'm minutes away from restoring the squirters. About this issue of too much oil pressure, is this a concern? I've never considered it. I'll try to get some numbers off of the rods. They are offset and look very similar to the others. I do remember that they also did not have the washer recess.

[Dodgeb4ya]

I agree with Don..I'd open up the squirt holes too. The bearing groove.. widen maybe a bit.

[greg g]

The author of the above referenced article say he gets 60 and 70 psi at street speeds.  He also mentioned a 1/4 in shim on the pressure relief spring. The Factory manual stated the at road speed, 10 #'s of oil pressure per for each 10 mph of road speed.   My engine runs 55 psi at cold startup, then idles at 35 and shows 45 to 50 at cruising speeds.  A couple members have reported stuck relief valves yielding a pegged oil gauge.  So its it 85 #'s or more?  As to why 60 + psi would be considered beneficial when the factory considered 40 to 50 optimal, your guess is as good as mine.  But I would think a stream of oil directed at the cam and the underside of the piston would be better than a misdirected splashing.

[TodFitch]

Its been way too long for me to even remember the equations much less be able to apply them, but I wonder. . .

 

When you increase the size of the groove you are decreasing the surface area of the bearing and thus increasing the bearing load per unit area. So this seems to be a trade off between oil volume and bearing forces, too much one way or the other will definitely affect bearing life. It would definitely be something the factory engineers would have thought about.

 

I know Don C noticed it, don't know how many others watched the whole thing. But on a video I posted the other day there was mention of engineers running 100 hour tests at 4000 RPM on car engines. Seems like that would be putting things into the zone where this type of issue would show up really quickly. I guess I should look up David Pollock's biography and see what his technical qualifications are/were.

[Don Coatney]

 I guess I should look up David Pollock's biography and see what his technical qualifications are/were.

 

Follow this link for an interesting ALLPAR article written by Pollock.

 

http://www.allpar.com/history/plymouth/plymouths-1949-1952.html

 

Amazon has the book (paperback) but not cheap. Used prices start at over fourty bucks.

 

http://www.amazon.com/gp/offer-listing/0879384913/ref=tmm_pap_used_olp_sr?ie=UTF8&condition=used&sr=&qid=

 

Forward look forum has discussed this same Pollock information.

 

http://www.forwardlook.net/forums/forums/thread-view.asp?tid=2621

[Dodgeb4ya]

Dave Pollock is a very knowledgable guy. I have talked to him several times before. He's been an old MoPar flathead guy for 40 years or more. I think he knows what he is talking about.

But everyone is on there own when seriously hot rodding a Mopar flattie especially the 23" engines. Drive it good and hard a little too long and it will start to knock, burn oil or just blow up. That would be awful! I'm not a racer. Stock slow and quiet is good.

[Plymouthy Adams]

I cannot think of one engine that Chrysler ever made that had any real performance potential was not exploited to some degree by the very factory in some avenue of of hot/sporty version.  The flattie was not really one of these...a few aftermarket companies made a few things for them here and there and to that end the very rumors of deficient subsytems/parts may have come to surface..but I assure you that if Ma Mopar realized any potential in the animal from day one it would have been touted on the dealership showroom floor..for instance the LA engine is available for race version in 4, 6, 8 and 10 cylinder versions..approx. 159 CI to 512 cubes...(2.6 to 8.4 ltr)  some engines were not ever considered anything other than a baseline economy moderate performer with only service and longevity in mind for its concept and ultimate use.

 

my 54 230 with 3.73 ratio and 2 speed auto takes full advantage of the gearing and torque multiplication factor and cruises nicely to about 83 MPH where it just starts to sound a bit busy..

Edited November 21, 2013 by Plymouthy Adams

[Dave72dt]

I've been told it takes certain amount of pressure to maintain the oil film between the brgs and the crankshaft and the faster it turns the more pressure it takes to maintain that protective film.  Bear in mind also the it takes more horsepower to develop that pressure since it is a resistant force and would also stress components such as drive gears and drive gear pins. removing some of the reliability of said components.  You increase the horsepower and commonly reduce the lifespan of the components.

[48Dodger]

No real point. Just random thoughts.

 

I've raced plenty. and I have the busted engines to prove it. 95 percent of my engine failures are crank related. The problem is the ability of the oiling system to keep up with the crank. The windage tray is important...."slow" spots in the gallery hurt....if your oil pressure rises (think of your finger over the end of a hose) it may actually be dropping the volume of delivered oil. The oil is thrown to the sides of the block, being held there by crank case pressure, increase in tempatures and bearing loads are breaking down the viscosity of said oil. If the oil pan is not baffled, the launch will throw the oil to the back of the pan and starve the pump.....I've always tried to build the motor last, cuz building the car/truck to the motor is tougher. But honestly, most engine failures at the track are building errors. Rod caps on backwards, cam retaining bolts backing out, missing gasket, freeze plug pops out, missing bolts, distributor not tighten down, etc, etc, etc,......good luck with your build. 

 

48D

[Don Coatney]

No real point. Just random thoughts.

 

 The oil is thrown to the sides of the block, being held there by crank case pressure,

48D

I have heard tell of some engines that run extreamly high RPM's that the oil in the crankcase will ball up around the spinning crankshaft and starve the pump. It is my understanding that many full race engine use a dry sump system to prevent this. In other words all return oil is sent to a remote reservior and the oil pickup is located there. I dont think that flathead 6 engines will ever have this "balling" issue as they are not capable of such righ RPM's.

 

I heard a story about a local circle track racer that had the racers edge by only running 4 quarts of oil in his engine. He gained a bit of horsepower by the low oil level as there was not enough oil in the crankcase to ball up. The track officials caught wind (intended pun) of this and forced him to run 5 quarts.

[BigDaddyO]

Smokey Yunick put a plexiglass window in a chevy oil pan and watched what happened to the oil. I believe he ran it up to around 7000 rpm.

The oil would 'follow' the crank and looked like ropes.

Then he designed a windage tray for it and that took care of that.

He also used plexiglass valve covers and a variable strobe light to watch and photograph what was going on at various rpms like valve float.

Edited November 23, 2013 by BigDaddyO

[BigDaddyO]

There is a nice little write up here;

www.chevytalk.org/fusionbb/showtopic.php?tid/92182/pid/634009/

 

It's a chevy site but the theory should be universal

[TodFitch]

Smokey Yunick put a plexiglass window in a chevy oil pan and watched what happened to the oil. I believe he ran it up to around 7000 rpm.

The oil would 'follow' the crank and looked like ropes.

Then he designed a windage tray for it and that took care of that.

He also used plexiglass valve covers and a variable strobe light to watch and photograph what was going on at various rpms like valve float.

7000 RPM? That works out to about 135 MPH with my car's gearing. Does not seem to be a problem to me for my use of the car.

 

By the way, Chrysler's top engineers did the same thing pre-WW1 when they worked for Studebaker. They determined that the then prevalent practice of using scoops on the rods did not work. Basically it just gouged troughs in the oil and did not scoop much oil into the rod bearings. So all the engines they designed from there on out had full pressure lubrication including all they designed for Chrysler Corporation. Carl Breer mentions his puzzlement on why other popular car brands (thinly veiled wording to mean Ford and especially Chevrolet) used splash feed for decades after his group had determined it was very bad practice.

[Oldindianrider]

When we rebuilt the 218 in my 48 ply this year I wanted to keep it stock looking but wanted to replace the bypass filter with a modern full flow type. This was done by drilling and tapping one hole in the block just above the oil pump into the pumps output galley. I then ran the output line around the rear of the block into a remote filter mount which was mounted where the original bypass filter had been mounted. The output line from the filter was then ran to the front of the oil gallery by attaching a elbow fitting in place of the oil gallery plug on the lower left front of the motor. The oil crossover pipe on the bottom of the block was removed and both holes plugged with pipe plugs. The two small oil line holes in the block for the bypass filter were also plugged . This gives a very stock looking setup with modern filtering. Remember you are supplying all your motors oil needs thru this line so use a line of sufficient size. All other aspects of the oil system were left stock.

To give credit where credit is due this method was not my idea but the idea of a friend of mine who modified his mopar flatheads this way many years ago.

[Fernando Mendes]

http://www.youtube.com/watch?v=mmmcj53TNic

FULL FLOW lubrication system

[Fernando Mendes]

Sequence of PARCIAL FLOW (PilotHouse engines):1)Oil Pump-----2)Crankshaft main bearings,Conecting Rod bearings,Camshaft bearings-----3)Inlet Oil Filter-----4)Outlet Oil Filter-----5)Relief Valve-----6)Oil Pan.

[Tim Keith]

I didn't completely cut off the cam bearings, I restricted them to 1/16" which is what mopar supplied as a rebuild reccomendatiin from what I have read.

 

I've read that others have also restricted the oil flow to the cam bearings.  Motor oil is also used for cooling.  How has this gone for you?  

[janan5243]

I have a question about oil filter for 49 Desoto. I am a newbie, just purchased car. It needs an oil change. still has original style throwaway can. will a remote spin on filter work properly. I intend to drive car as much as possible. any ideas on simple power increase to give the car a little more oomph for where I live. upstate new York, lots of hills.

[Don Coatney]

I have a question about oil filter for 49 Desoto. I am a newbie, just purchased car. It needs an oil change. still has original style throwaway can. will a remote spin on filter work properly. I intend to drive car as much as possible. any ideas on simple power increase to give the car a little more oomph for where I live. upstate new York, lots of hills.

If your engine has the diamond 4 hole "boss" (shown in the photo below just to the right of the distributor) you can convert to a full flow oil filter. Some Desoto engines have this feature some do not.

 

 

[_shel_ny]

If you do not have the "boss".

 

Add a replaceable element  type,or

 

http://p15-d24.com/topic/35616-new-guyremote-oil-filter/?hl=spin#entry363396

 

or

 

http://p15-d24.com/topic/35810-embarrasing-question-how-do-i-change-this-oil-filter/

[55 Fargo]

I cannot think of one engine that Chrysler ever made that had any real performance potential was not exploited to some degree by the very factory in some avenue of of hot/sporty version.  The flattie was not really one of these...a few aftermarket companies made a few things for them here and there and to that end the very rumors of deficient subsytems/parts may have come to surface..but I assure you that if Ma Mopar realized any potential in the animal from day one it would have been touted on the dealership showroom floor..for instance the LA engine is available for race version in 4, 6, 8 and 10 cylinder versions..approx. 159 CI to 512 cubes...(2.6 to 8.4 ltr)  some engines were not ever considered anything other than a baseline economy moderate performer with only service and longevity in mind for its concept and ultimate use.

 

my 54 230 with 3.73 ratio and 2 speed auto takes full advantage of the gearing and torque multiplication factor and cruises nicely to about 83 MPH where it just starts to sound a bit busy..

hmmm Tim, 83 mph,28 inch tires and 3.73 gears, and 3700 RPM, no wonder it sounds busy, most likely on the verge of explosion....

[janan5243]

I had the post about replacing the oil canister with a spin on. I purchased canister type from dodgemont on e-bay.

"Came off a 48 Plymouth" Has a tube running up the center from bottom. If I'm thinking correctly, inlet is bottom fitting & output is top fitting. Please correct me if wrong.

[Don Coatney]

This is from a Desoto shop manual. What does your shop manual say?

 

[Merle Coggins]

Are there "IN" and "OUT" markings anywhere near the ports? Different filters were designed differently. Mine is from the Deluxe Filter Company and has the inlet at the bottom. The oil flows from the inside out on the sock type element. After the oil oozes through the filter it collects at the top where the outlet port is connected to the return port on my engine.

 

Merle