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at the end of my engine build and have this last item to sort. Looking for advice on the windage tray. Its there a better alternative to spacers as the factory trays have reported fatigue problems. Butler has one they say can handle up to 2.5 stroke and requires a mod to the dip stick. I am leaning in the direction at the moment.
 

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at the end of my engine build and have this last item to sort. Looking for advice on the windage tray. Its there a better alternative to spacers as the factory trays have reported fatigue problems. Butler has one they say can handle up to 2.5 stroke and requires a mod to the dip stick. I am leaning in the direction at the moment.
I would go with the Butler item. However, when they built my stroker short block, they convinced me to just go without a windage tray completely. I am just street/strip so not looking for every single bit of power. Seems fine so far and Pontiac did stop using them at some point in 70s I believe.
 

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My personal opinion is that you really don't need one for the street. It may be a worthy item if you were planning on turning higher RPM's and wanted every extra HP you can wring out of your engine.

What is more important is pan baffling. The later Pontiac pans had a baffle in them from the factory - I think 1972/73 they came out with this? Keeping the oil in the pan during hard acceleration and braking so the oil pick-up is submerged in oil in my opinion is more important, so a good pan, is where I would spend my money. The factory pan with baffle is a minimum. Aftermarket pans have more baffling and even "trap doors" to keep the oil in the pan, but they are expensive and may be a little over kill on the street.

The purpose of the windage tray is to create a barrier between the crank throws and oil level in the pan. It is said that the crank throws at higher RPM's will lift oil up from the pan and whip it around. The oil that gathers on the crank throws is said to create additional drag on the crank as it spins. Hmmm.

As higher RPM's are reached, the oil pump is pumping more oil and more oil means it is going through the engine and what was once 5 quarts of oil may now be only 3 quarts. So the level of the oil has now dropped and the crank throws are further away from what oil is left in the pan. To lift the lowered level of oil up from the pan at higher RPM's would take a lot of air movement from the crank throws. Now Chrysler, during their racing heydays, stated that the crank throws needed to be 6 inches away from the oil level in the pan. So they recommended not using a windage tray and using a deeper pan/pick-up and not filling it to capacity, ie a 7/8 qt pan would be filled with 4/5 quarts of oil to keep the oil level lower and away from the crank throws.

Another thing I think about is the the factory windage tray can hinder oil return to the pan. Look at your tray. How many small drain holes do you see? So all the oil from the top end gets returned via the tray and has to return to the pan through those small holes. Milt Schornack in blueprinting his engines for Royal used to open up the 3 drain holes to 1" and add a 4th hole to help the oil drain back into the pan more quickly. I want oil in my pan, and quickly, so the oil pick up doesn't suck air. Photo enclosed.

With the lower zinc counts in some oils, the crank also slings oil around inside the block. Some of that oil is splashed on the cam. My thinking is that I want all the oil I can hitting that cam and keeping the cam lobes and lifters oiled up. So what if I lose 10-15 HP from parasitic oil drag at 6,000 RPM's? First, I won't be spinning 6K and second, 10 HP at the flywheel is about 3, or 4 HP at the rear tires. Think I'll feel the difference?

Now as Bear has pointed out, the aftermarket Spotts windage tray looks to be a better choice than the factory tray if you are going to use one. It does its job as a windage tray and allows for faster/better oil drain back. You will still get oil splashing around by the crank as oil that goes to the rod/crank bearings bleed out of those bearings under pressure. The bigger the clearance the more the oil "leak."

The crank scraper can be a good idea. It has to be fitted to the crank to meet a specific clearance/gap between the scraper and crank throws. What this does is just what it says, scrapes excess oil off the crank throws as it rotates past/through the scraper. So the oil that collects on the crank throws as it whips over and past the oil level in the pan is essentially scraped off if you have set the tolerances correctly.

OK, my opinion again as based on what I am doing with my 455/469CI build. Engine will most likely be spun to about 5,600 RPM's IF it does not run out of cam/head flow CFM's first. No windage tray. This will allow for better oil drain back into the pan - plus I am OK with splash oil reaching my cam. I'll make sure I have the correct bolt-on intermediate dipstick tube when not using the tray - as Pontiac did. Factory Pontiac baffled pan BUT, I purchased an oil pick-up for a deeper oil pan and will cut the buttom off my factory pan, bolt up my oil pump/pick up, and then add the required sheet metal to extend the pan so its bottom gives me the needed clearances between the pump pick up and pan bottom. This will create distance between the crank throws and oil level as I will not fill the pan anymore than the factory fill of 5 qts. I am using a crank scraper which will pull any excess oil off the crank throws and hold down any excess oil being tossed around in the block.

You have options. What is the correct or best way to go about it? It depends on what you feel is best - stock, modified, street/strip, race, etc. may each have a different application in how you wold tackle the use of a windage tray, crank scraper, deeper pan, baffled pan, baffled pan with trap doors. A lot of choices and a lot of opinions. Might I be completely wrong in my thinking and what I am setting up for my 455? Perhaps, but from my research, it seems to make sense to me so I am going with it.

Pontiac Baffled Pan.jpg
Pan & Windage Tray.JPG
 

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My personal opinion is that you really don't need one for the street. It may be a worthy item if you were planning on turning higher RPM's and wanted every extra HP you can wring out of your engine.

What is more important is pan baffling. The later Pontiac pans had a baffle in them from the factory - I think 1972/73 they came out with this? Keeping the oil in the pan during hard acceleration and braking so the oil pick-up is submerged in oil in my opinion is more important, so a good pan, is where I would spend my money. The factory pan with baffle is a minimum. Aftermarket pans have more baffling and even "trap doors" to keep the oil in the pan, but they are expensive and may be a little over kill on the street.

The purpose of the windage tray is to create a barrier between the crank throws and oil level in the pan. It is said that the crank throws at higher RPM's will lift oil up from the pan and whip it around. The oil that gathers on the crank throws is said to create additional drag on the crank as it spins. Hmmm.

As higher RPM's are reached, the oil pump is pumping more oil and more oil means it is going through the engine and what was once 5 quarts of oil may now be only 3 quarts. So the level of the oil has now dropped and the crank throws are further away from what oil is left in the pan. To lift the lowered level of oil up from the pan at higher RPM's would take a lot of air movement from the crank throws. Now Chrysler, during their racing heydays, stated that the crank throws needed to be 6 inches away from the oil level in the pan. So they recommended not using a windage tray and using a deeper pan/pick-up and not filling it to capacity, ie a 7/8 qt pan would be filled with 4/5 quarts of oil to keep the oil level lower and away from the crank throws.

Another thing I think about is the the factory windage tray can hinder oil return to the pan. Look at your tray. How many small drain holes do you see? So all the oil from the top end gets returned via the tray and has to return to the pan through those small holes. Milt Schornack in blueprinting his engines for Royal used to open up the 3 drain holes to 1" and add a 4th hole to help the oil drain back into the pan more quickly. I want oil in my pan, and quickly, so the oil pick up doesn't suck air. Photo enclosed.

With the lower zinc counts in some oils, the crank also slings oil around inside the block. Some of that oil is splashed on the cam. My thinking is that I want all the oil I can hitting that cam and keeping the cam lobes and lifters oiled up. So what if I lose 10-15 HP from parasitic oil drag at 6,000 RPM's? First, I won't be spinning 6K and second, 10 HP at the flywheel is about 3, or 4 HP at the rear tires. Think I'll feel the difference?

Now as Bear has pointed out, the aftermarket Spotts windage tray looks to be a better choice than the factory tray if you are going to use one. It does its job as a windage tray and allows for faster/better oil drain back. You will still get oil splashing around by the crank as oil that goes to the rod/crank bearings bleed out of those bearings under pressure. The bigger the clearance the more the oil "leak."

The crank scraper can be a good idea. It has to be fitted to the crank to meet a specific clearance/gap between the scraper and crank throws. What this does is just what it says, scrapes excess oil off the crank throws as it rotates past/through the scraper. So the oil that collects on the crank throws as it whips over and past the oil level in the pan is essentially scraped off if you have set the tolerances correctly.

OK, my opinion again as based on what I am doing with my 455/469CI build. Engine will most likely be spun to about 5,600 RPM's IF it does not run out of cam/head flow CFM's first. No windage tray. This will allow for better oil drain back into the pan - plus I am OK with splash oil reaching my cam. I'll make sure I have the correct bolt-on intermediate dipstick tube when not using the tray - as Pontiac did. Factory Pontiac baffled pan BUT, I purchased an oil pick-up for a deeper oil pan and will cut the buttom off my factory pan, bolt up my oil pump/pick up, and then add the required sheet metal to extend the pan so its bottom gives me the needed clearances between the pump pick up and pan bottom. This will create distance between the crank throws and oil level as I will not fill the pan anymore than the factory fill of 5 qts. I am using a crank scraper which will pull any excess oil off the crank throws and hold down any excess oil being tossed around in the block.

You have options. What is the correct or best way to go about it? It depends on what you feel is best - stock, modified, street/strip, race, etc. may each have a different application in how you wold tackle the use of a windage tray, crank scraper, deeper pan, baffled pan, baffled pan with trap doors. A lot of choices and a lot of opinions. Might I be completely wrong in my thinking and what I am setting up for my 455? Perhaps, but from my research, it seems to make sense to me so I am going with it.

View attachment 135726 View attachment 135727
I'm running one from Spotts Performance in my 461. Using his crank scraper too. Love them both. Very well made.
Bear
PJ is right. I forgot about the baffling for oil pick up. A crucial detail. I did go with a new baffled oil pan as well. Cool pictures too, PJ. I never saw the innards of of a Royal Pontiac motor before.

And at the same time, even though BearGFR is just up the road, I will politely decline if he requests to race me. I suspect I would be left in a cloud of dust. I know he is wringing out every bit of power from the monster motor of his.
 

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Discussion Starter #7
My personal opinion is that you really don't need one for the street. It may be a worthy item if you were planning on turning higher RPM's and wanted every extra HP you can wring out of your engine.

What is more important is pan baffling. The later Pontiac pans had a baffle in them from the factory - I think 1972/73 they came out with this? Keeping the oil in the pan during hard acceleration and braking so the oil pick-up is submerged in oil in my opinion is more important, so a good pan, is where I would spend my money. The factory pan with baffle is a minimum. Aftermarket pans have more baffling and even "trap doors" to keep the oil in the pan, but they are expensive and may be a little over kill on the street.

The purpose of the windage tray is to create a barrier between the crank throws and oil level in the pan. It is said that the crank throws at higher RPM's will lift oil up from the pan and whip it around. The oil that gathers on the crank throws is said to create additional drag on the crank as it spins. Hmmm.

As higher RPM's are reached, the oil pump is pumping more oil and more oil means it is going through the engine and what was once 5 quarts of oil may now be only 3 quarts. So the level of the oil has now dropped and the crank throws are further away from what oil is left in the pan. To lift the lowered level of oil up from the pan at higher RPM's would take a lot of air movement from the crank throws. Now Chrysler, during their racing heydays, stated that the crank throws needed to be 6 inches away from the oil level in the pan. So they recommended not using a windage tray and using a deeper pan/pick-up and not filling it to capacity, ie a 7/8 qt pan would be filled with 4/5 quarts of oil to keep the oil level lower and away from the crank throws.

Another thing I think about is the the factory windage tray can hinder oil return to the pan. Look at your tray. How many small drain holes do you see? So all the oil from the top end gets returned via the tray and has to return to the pan through those small holes. Milt Schornack in blueprinting his engines for Royal used to open up the 3 drain holes to 1" and add a 4th hole to help the oil drain back into the pan more quickly. I want oil in my pan, and quickly, so the oil pick up doesn't suck air. Photo enclosed.

With the lower zinc counts in some oils, the crank also slings oil around inside the block. Some of that oil is splashed on the cam. My thinking is that I want all the oil I can hitting that cam and keeping the cam lobes and lifters oiled up. So what if I lose 10-15 HP from parasitic oil drag at 6,000 RPM's? First, I won't be spinning 6K and second, 10 HP at the flywheel is about 3, or 4 HP at the rear tires. Think I'll feel the difference?

Now as Bear has pointed out, the aftermarket Spotts windage tray looks to be a better choice than the factory tray if you are going to use one. It does its job as a windage tray and allows for faster/better oil drain back. You will still get oil splashing around by the crank as oil that goes to the rod/crank bearings bleed out of those bearings under pressure. The bigger the clearance the more the oil "leak."

The crank scraper can be a good idea. It has to be fitted to the crank to meet a specific clearance/gap between the scraper and crank throws. What this does is just what it says, scrapes excess oil off the crank throws as it rotates past/through the scraper. So the oil that collects on the crank throws as it whips over and past the oil level in the pan is essentially scraped off if you have set the tolerances correctly.

OK, my opinion again as based on what I am doing with my 455/469CI build. Engine will most likely be spun to about 5,600 RPM's IF it does not run out of cam/head flow CFM's first. No windage tray. This will allow for better oil drain back into the pan - plus I am OK with splash oil reaching my cam. I'll make sure I have the correct bolt-on intermediate dipstick tube when not using the tray - as Pontiac did. Factory Pontiac baffled pan BUT, I purchased an oil pick-up for a deeper oil pan and will cut the buttom off my factory pan, bolt up my oil pump/pick up, and then add the required sheet metal to extend the pan so its bottom gives me the needed clearances between the pump pick up and pan bottom. This will create distance between the crank throws and oil level as I will not fill the pan anymore than the factory fill of 5 qts. I am using a crank scraper which will pull any excess oil off the crank throws and hold down any excess oil being tossed around in the block.

You have options. What is the correct or best way to go about it? It depends on what you feel is best - stock, modified, street/strip, race, etc. may each have a different application in how you wold tackle the use of a windage tray, crank scraper, deeper pan, baffled pan, baffled pan with trap doors. A lot of choices and a lot of opinions. Might I be completely wrong in my thinking and what I am setting up for my 455? Perhaps, but from my research, it seems to make sense to me so I am going with it.

View attachment 135726 View attachment 135727
This is great information and is very logical way of looking at the problem. Thanks Jim.
 

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Watch "Engine Masters" Episode 32 for an interesting look at this topic.
Apparently you cannot watch the entire video unless you subscribe to Motor Trend. That's a shame because I always enjoyed their video's and testing sessions.


These guys make it seem like a new discovery. Not so. As I pointed out, Chrysler engineering knew this back in the 60's - keep the oil level 6 inches away from the crank throws and no windage tray. Kicking up and churning oil aerates the oil and that can be a bad thing. What was not mentioned is a windage tray of any type. I know some aftermarket pans have one built in, but I assume this pan has none and was just an 8 qt (or 7?) capacity pan and I don't know if the engine itself has any form of windage tray. To complete this type of test, and they may have in another episode, would then be to compare a pan/engine windage tray, crank scraper, or even a kick-out style pan at full 8 quarts for each test and then lower the oil 1 Qt at a time to show any improvements using any of the fore mentioned changes or combinations of them.

The Chrysler engineers were top notch and knew how to extract every HP out of an engine. That was what put the Hemi on the map and won so many races that NHRA had to introduce the "dial in" type racing where you had to post a dial-in, ie how fast your car was going to run the 1/4 mile. By doing this, you were essentially racing against yourself. But this allowed a 4 cylinder 28 second 1/4 mile car to run against a 9 second 1/4 mile Hemi. The 28 second car got the difference in a "head start" and theoretically both cars would be equal at the finish line. Chrysler dropped out of factory racing and figured why spend all the money on going heads-up fast when you could soup up a Dodge Colt and win against any high dollar build. Stock and Super Stock racing was never the same. (y)
 
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