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Bryan

Will not Cross Drill my crank

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I'm trying to understand why anyone would cross drill their crank, even for RPMs above 4,000.   Conflicting info from posts, one says "Cross drill crankshaft from #5 to the 3rd main and #2 from the 2nd main". Another says " between #5 & #4 and #2 and #3 main bearings".  Looks like from the Dodge oil diagram that lower rod ends are covered.   1 & 6 are covered by 1 passage each from 1st & 4th mains respectively, but they are furthest from the middle feed.   Lower ends  2 & 3 covered by 2nd main, 4 & 5 covered by 3rd main.   See attached picture . Could someone explain how it would improve oiling?

Oil passages 230.jpg

Edited by Bryan
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Also by reading other forums, some mention the centrifugal forces in the crank as a factor.  Notice that all the feeds from mains are to lower rods that are slinging oil outwards down the passage as the journal rotates.  An added passage from #1 to # 2 would have the oil trying to leave #1 against  the centrifugal force of rotation.   Don't think I'll be messing with having my crank drilled...I won't be in a tractor pull with my 48 Dodge.

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The best way to improve oiling, in my opinion,  is to enlarge the groove (annulus) in the main bearing shells.  Keep in mind that it does reduce the bearing area.   To do this, on a lathe, the shells can be held  in a fixture made of two discarded center main caps fastened to a face plate or held in a four jaw chuck. Then reach in with a boring bar or similar tool.  

Some 217 - 230 main sets do not have a groove on the lower shells.  I have always installed  grooved shells on the bottom halves even though bearing sets are pretty costly to break up.

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For 99% of us cross drilling a crank is a solution to a problem that doesn't exist.  These engines will take quite a beating in stock form and I don't hear of a lot of lower end problems caused by oiling.  Chamfer the existing oil holes in the crank, radius it correctly and maybe shim the pressure relief spring (maybe not)  motor on...

Adam

EDIT: Full grooved main bearings might not last long as you loose the hydrodynamic wedge.

Edited by Adam H P15 D30

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Full groove bearing were once state-of-the-art for drag racing and such. I do believe that even NASCAR engine builders have moved away from any grooves in order to increase surface bearing and better maintain the fluid wedge.

The usefulness of cross-drilling is a factor the oil system design itself. Some engines benefit more than others. 

The bottom line is that you need to have oil at all times at all places.

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For the OP needs unless he is building a race engine or tractor pulling etc he is just fine without grooving or cross drilling.

He will be good to 4500 to 5000 rpm just fine.

Speak to George Asche or Tim Kingsbury for some serious consultation on this topic they are the experts.

The majority in here on reapeat heresay and do not have real world experiences to support their statements.

 

 

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Glad to enter into this discussion.   I increased the depth of the grooves in the 251 I put into my 51 Plymouth.

It has run without any trouble for over 50 000 miles.  The reason I did this was I felt a little more oil  at the rods  would be of benefit in an engine with an 060 overbore and 8.4 to 1 compression.   But to be fair, I have run stock rebuilds farther and had no problems either.

I have a 230 with a spray welded crank.  It has given trouble with excessive wear on certain con rods.  A partial teardown revealed welding slag in the  oil passages. (not loose)   Since it will take a complete teardown to redrill  these passages, I have opted to replace the engine.

Edited by dpollo

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Keep in mind the the quality assurance folks at the engine assembly lines pulled random engines from the line, mounted them on a dyno, and ran them for 50 hours at 3600 rpm.  That works out to about 3000 non stop miles at peak HP, against a load.  I guess this would be a pretty thorough challenge of any weakness in the oiing system.  I would put my money on properly fit new bearings and perhaps a higher volume oil pump on a cleaned out system, for any rebuild meant to operate on any road anywhere on the earth's surface.

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Greg, interesting that you mention a higher volume oil pump..........does such an animal exist for the side valve engines? or is there a way to increase volume from an original pump?...........when I was collecting bits for the proposed 230 a few yrs ago I purchased a new pump which had a different internal vane/thingamajig..........lol............to the one that the 230 industrial engine had, from what I could work out the internal thingamajig was changed in the late 40's/early50's..............but I couldn't find any reference to an increase in volume tho' the pressure is regulated by the relief valve spring.............is that right...............I love it when we talk dirty...........lol.............andyd 

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That's what I would want, something simple like a slightly higher volume pump,since I'm learning it's not the pressure. Pressure is from the resistance in the system..volume is more important.   Planning on saving my money for balancing the crank, rods and pistons as a system.

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The oiling system is covered in a Chrysler Technical film  which can be found elsewhere on this forum.  Look for Bryan's post on page 2 of  Help picking an engine for my 40 Chrysler ....Of course, you have already seen it, Bryan. but it is pretty good.

The gyrotor pump as found on all post war engines provides more than enough volume for all situations, even the engine oil filled torque converters of 53 and 4

Edited by dpollo
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Don't know how you push more fluid through a system with a defined capacity.  But I guess since it drains to the sump through open air the potential is there.  Maybe some one can OK up MoPaR part number 

Edited by greg g

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On ‎11‎/‎7‎/‎2017 at 12:27 PM, 55 Fargo Spitfire said:

For the OP needs unless he is building a race engine or tractor pulling etc he is just fine without grooving or cross drilling.

He will be good to 4500 to 5000 rpm just fine.

Speak to George Asche or Tim Kingsbury for some serious consultation on this topic they are the experts.

The majority in here on reapeat heresay and do not have real world experiences to support their statements.

I didn't know these guys were crank experts too? I though George was the expert on carbs, manifolds, and overdrives. And Tim is the new guy taking over George's business...?

Agreed that the original poster is right in not feeling the desire to cross drill is crank.

These engines are low revving motors...good up to about 3500, they should go up into the 4k - 5k range, even if possible.

Edited by John-T-53

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These engines had a highly advance oiling system for their day.

Speaking from real world experience, the most important thing that one can do, if undertaking a rebuild, is to maintain specified tolerances throughout, and have quality machine work done. Good crank grinders are getting more scarce these days. It's imperative to have a crank grinder, with a good crank grinding machine, that knows how to size journals appropriately to the correct limit range based on the bearings that he should already have in hand, which will ensure even oil supply across all journals.

If I were to attempt any improvements in the oil system of one of these motors, I would examine the pan baffling and perhaps look at adding full-flow filtration.

 

 

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3 hours ago, John-T-53 said:

I didn't know these guys were crank experts too? I though George was the expert on carbs, manifolds, and overdrives. And Tim is the new guy taking over George's business...?

Agreed that the original poster is right in not feeling the desire to cross drill is crank.

These engines are low revving motors...good up to about 3500, they should go up into the 4k - 5k range, even if possible.

Well I guess you are a bit misinformed John, not sure why you assume AoK doesn't built engines, really?

At any rate, George is most likely the most knowledgeable man alive today, that is an expert on these engines, how to build these engines for performance etc, how many of these engines have you built John?

Don't be making totally uninformed statements like these engines only rev to 3500 rpm tops, what a fallacy.

Okay here is my bone stock, tired 228 engine, dual carbs and exhaust, spinning up to 4000 rpm, like nothing.

BTW I was in 3rd gear doing damn near 60 mph ( my speedo reads 10mph slow) before shifting into 4th gear direct drive.

So you and, I 'm guessing possibly Don  ( he likes your posts and recall him stating over 3500 RPM is not attainable on a nearly stock engine) making statements of not revving to over 3500 very easily in a stock or near stock engine does not cut it.

These engines in a factory setting were run at 3600 RPM on a load for 50 hours of testing, do you or anyone else think that's just marketing hype?

Okay here are 3 modified engines, 1 extremely modified and 2 fairly radical too. Note the race engine blipping to 5000 RPM without a load, this engine would most likely hit over 6000 RPM. Many tractor pulling 265 engines will bang up to over 5000 rpm for the pull event.

In this world there are a few Chrysler flathead experts, on building engines, and designing and building speed parts, Tim Kingsbury and George Asche Jr happend to be 2 of these people, George has been building these engines since 1949, he might be the most experienced and knowledgable builder of these engines in the entire world.

On this forum, we have some real knowledgeable engine builders too, Dpollo is another such individual, has built many of these engines, and has been at it for 50 years.

I scratch my head often on some of the conjecture that is spread out on this forum and wonder why this still persists....

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Edited by 55 Fargo Spitfire

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Does anyone know the texture of the existing oil passages in the crank and whether polishing them (if rough) would improve flow?  I read that flow rates in pipes are affected by roughness (PVC vs concrete). Y'all stay calm..

Edited by Bryan

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19 hours ago, John-T-53 said:

I didn't know these guys were crank experts too? I though George was the expert on carbs, manifolds, and overdrives. And Tim is the new guy taking over George's business...?

Agreed that the original poster is right in not feeling the desire to cross drill is crank.

These engines are low revving motors...good up to about 3500, they should go up into the 4k - 5k range, even if possible.

Hey John -  Just to clarify as I sit here laughing while reading your post,  I am definitely not taking over George's business or anything close to that. Ive know George for over 20 years. George has been building performance flathead engines for over 60 years. His 1929  Desoto which he still owns was undefeated at the Flying Mile on Daytona Beach in 1955 at 142 mph. That highly modified 265ci engine was built by George.  George built the engines for his Uncle Harry Hiens who is in the nascar hall of fame. Those flathead engines were legendary for beating all kinds of v8s.   My family background dates back to my Grandfather who worked for Chrysler starting in the 1930s, my Dad who was also an automotive engineer, who build flathead stock car engines in the 50s and 60s, later moving on to building engines for a number of well known top fuel racers.  My background really pales in comparison to all of those, although have grown up around some of the best and brightest in the industry.While I do have an automotive engineering degree, it was definately not where the bulk of my career focused by any stretch.  I did run a car in the pro stock class in the 1970s and owned the track record at Toronto International when it closed. While I helped build a couple of engines for that car, it was really as an assistant as it was primarily both of my grandfathers that were the primary builders along with my Dad.  

I have been fortunate to have known George Asche Jr and he and his family have enjoyed a special bond with my family for a long time. From that yes with George, my Dad Eddy along with a buddy I went to school with and myself we did come up with a couple of performance intakes.   As you point out that is likely where George and I are likely better known  and your also correct George  would be pretty well known for his building of overdrives, carbs, linkage etc.

But that really is a tip of the iceberg in many ways.  George had built likely 50 performance engines since I have known him, and maybe that is a conservative number.   In the last 5 years I know he has build 18 of them.  Now I think its safe to say that he would say, as my Dad would have while he was still alive as I would, were always interested in learning more about flathead mopar engines, and improving them. None of use pretend to know everything about them in terms of improving their performance.

That being said,  let me say this about the topic of oiling.  There are lots of things you can do to improve the oiling.  1st thing with any rebuild is to simply turn the two cam bearings from using the big hole, which is how they came from the factory, to using the small hole.  There is way more oil hitting the cam than was ever needed.  Next make sure you have good oil pressure, which really is a way of saying make sure you have a good oil pump.  Yes there were higher volume oil pumps for trucks. Yes we try and use them on higher rpm builds but for 99% of every engine I hear being built its not required.

I could go though a bunch of tips but unless your planning on spinning your engine above, let me peg it at 5000 rpm regularly and your running a long stroke engine,  you dont need it.   Use the small hole in the cam bearing, make sure your have a good oil pump and drive on drive on.

In terms of a couple of race engines.. Attached are pictures of a 1933 Plymouth. Its spent its life as a road racer. It was highly competitive at the Brickyard at Indy and was a engine build by a well known engine builder.    Its owner found out the hard way that yes there is a portion of the track with a bank on it, and as he rode up the bank to pass a Porsche   and a Ferrari he lost oil pressure and it locked up. It literally bent a rod and  another rod broke loose and went through the block.   George  was called on to build the new engine for the car, and what I will say is in this years season, the car  which has always been competitive, rose up the ranks significantly  and the performance improvements were categorized by its owner as "simply incredible how much additional power it has"..  Here is was recently as it has finished off the race season and was brought back to George for some further improvements, including changing the fuel distribution, and changing the rear end gearing. This engine is capable of in excess of 6000rpm

 

and of course another video of the AoK dragster (which for you trivia fans, AoK was a name George came up with..  It stands for Asche over Kingsbury)..    and George's official answer to the question of  -  " how fast is that car"..     Answer - "Its faster than the average Echo"  Aka The Toyota Echo.. 

 

 

 

A couple of things off topic I like to note here putting to rest the myth that you need electronic ignition for a performance engine, this engine runs an original Chrysler dual point distributor with points!  Yes its been modified, but there is no electronic ignition.   Yes we also do have a magneto set up for the car to eliminate the battery but what we were puddling with here is trying to get the idle off of the stall which used to be around 2000 rpm.  Now down to just over 1000 rpm, its quite easy to drive.

Back to the oiling in the engine. Yes we  grooved bearings, and did some internal drilling and modifications to get oil return. We have a windage tray with crank scrapers for pulling off oil as this engine spins well above 7000 rpm.

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A couple of still shots of the dragster and in answer to the question of how about some videos of it running. Well they will be coming and they do already exist, but for a couple of reasons, including an non-disclosure agreement we cant post them publicly at this point.

 

Again, my apologies for the slight wavering from the original thread intent, but I really couldn't resist and have tried to also clarify the relative oiling points I think the originator of the thread was looking for.

 

Tim

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Surprised to see the big box store 4 inch paper filters on a race engine.  Seems they would be to restrictive for the application.  But since each carb is only flowing 33% of total intake maybe they work.  I made up an oval deal that uses a filter element that prvdes about three times the filtering element of that style filter.

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1 hour ago, greg g said:

Surprised to see the big box store 4 inch paper filters on a race engine.  Seems they would be to restrictive for the application.  But since each carb is only flowing 33% of total intake maybe they work.  I made up an oval deal that uses a filter element that prvdes about three times the filtering element of that style filter.

Stacked works well for me.

P6230003.jpg

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4 hours ago, timkingsbury said:

Again, my apologies for the slight wavering from the original thread intent, but I really couldn't resist and have tried to also clarify the relative oiling points I think the originator of the thread was looking for.

 

That helped a lot ..not planning to run over 4,000 RPM much but I only want to overhaul my engine one time. I want it to be reliable if I have to cruise at 65 for any distance. Only think I would be doing that if I was going to a car show or club meeting.  I might add a pre-oil electric pump or reservoir tank to circulate oil before starting (it won't be a daily driver).  Since we're off topic, any opinions on the original thick ring pistons?   I'm toying with the idea of custom pistons with the same skirt, but changing to a modern 3 ring setup.

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6 hours ago, greg g said:

Surprised to see the big box store 4 inch paper filters on a race engine.  Seems they would be to restrictive for the application.  But since each carb is only flowing 33% of total intake maybe they work.  I made up an oval deal that uses a filter element that prvdes about three times the filtering element of that style filter.

The challenge he has is the same challenge I have on my 1949 Plymouth Business coupe, and that is the back air cleaner is so close to the firewall.  The actual diameter of the air filter  is actually only part of the equation when it comes to air filters.  Its the total amount of square inches or square feet of media surface that is actually the key number.  Obviously the larger the diameter and larger the height the more opportunity there is to utilize filter media. I mention that as on my car I am actually using a custom made filter media which has almost 3 times the total media area of the ones the owner of the 1933 Plymouth put on his car.  Improving the air flow is one of the items on the agenda to improve on the car.    With the help of a friend were actually working on off setting  what are known as 7" round air cleaners.  That being said there is nothing wrong with oval designed air cleaners. Would love to have a look at your creation.

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3 hours ago, Bryan said:

That helped a lot ..not planning to run over 4,000 RPM much but I only want to overhaul my engine one time. I want it to be reliable if I have to cruise at 65 for any distance. Only think I would be doing that if I was going to a car show or club meeting.  I might add a pre-oil electric pump or reservoir tank to circulate oil before starting (it won't be a daily driver).  Since we're off topic, any opinions on the original thick ring pistons?   I'm toying with the idea of custom pistons with the same skirt, but changing to a modern 3 ring setup.

While a pre oil pump or sump design is certainly an improvement, its over kill and definitely not anything  your going to need.

 

On pistons,  again, for what your talking its over kill. Cast pistons with 4 rings  are more than capable of running a couple of hundred thousand miles.  Now in terms of original pistons and rings, well right off the bat it depends on what engine your talking about. There were forged pistons and cast pistons, as well as chrome rings and cast rings used over the decades in flathead mopars.   But for a discussion on  which is better, original 1930-1959 technology verses modern forged pistons and modern rings well there is little question which is better. We use custom pistons are rings all the time. The biggest issue is simple.. They are expensive.

But in my 1949 Plymouth or our dragster,   they are Venola Top Fuel Pistons,  coated with plasma moly rings. They are smaller, lighter, stronger  and....  expensive. I will attach a picture of a modern forged piston sitting beside an OEM 265 ci piston from 1954.   The last 6 pictures are the pistons we had custom made for the 1933 Plymouth race car, and as you can see the rings are super thin.

But back to your engine your describing, you dont need that.  You should be able to do a rebuild with  decent cast pistons,   decent bearings etc and never have to rebuild it again. Even if you want to bore it out a bunch, regrind the cam to some mild custom grind, deck the block, shave the head etc,  you dont need pre-oil pump and custom pistons.  But then, lol, there is lots I dont really need but I have anyways, so by all means fill your boots.

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17 hours ago, Bryan said:

That helped a lot ..not planning to run over 4,000 RPM much but I only want to overhaul my engine one time. I want it to be reliable if I have to cruise at 65 for any distance. Only think I would be doing that if I was going to a car show or club meeting.  I might add a pre-oil electric pump or reservoir tank to circulate oil before starting (it won't be a daily driver).  Since we're off topic, any opinions on the original thick ring pistons?   I'm toying with the idea of custom pistons with the same skirt, but changing to a modern 3 ring setup.

Since you are in it this far (and you asked) I would have a set of modern 3 ring pistons made and while you're at it find a set of longer 218 rods.  Then recalculate your total height to 0 deck.  Though you have no plans to rev it higher than 4000 rpm, the long stroke makes the piston speeds very high in our old engines, coupling that with 4 rings on our OE pistons....  Also you get the advantage of a longer rod and moving the wrist pin higher inside the piston.  Is all this necessary, probably not. Will our old engines run a very long time without modifications, you betcha. But since you are there anyway spending thousands on a proper rebuild, what's an extra few hundred bucks to improve the design a little?  If I had to go through my 230, I would spend the money on pistons and longer rods first.

Adam

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