322 Windage Tray

[Beemon]

When I did my rear main seal in my 56 322, there wasn't a windage tray. I didn't even know they existed. What year 322s came with windage trays and will they go into a 56 322? Also is there any real advantage to adding a windage tray?

[EmTee]

3 hours ago, Beemon said:

Also is there any real advantage to adding a windage tray?

 

Well, in a street car probably not.  If done properly, it keeps the oil in the sump from being picked-up by the rotating assembly and slung all over.  It basically helps reduce drag on the crankshaft.  It may, therefore, reduce the amount of oil slung onto the lower cylinder bores too.  I'd think a windage tray would make the rear main seal's job a little more manageable (i.e., less likely to leak).  In my cars I try to avoid filling the crankcase all the way up to (or worse, over) the FULL mark.  I try to run about 1 pint 'low' (midway between ADD and FULL.  That way the oil level should normally stay below the crankshaft and those 40 year-old gaskets and seals don't get flooded.

[NTX5467]

Back when your '56 was less used, there were some engines which slung-out (to unknown parts) the top quart of oil in the crankcase, then it remained constant for several thousand miles more.  Others "used" oil linearly, if at all, at varying rates.  Back then, nobody really had any explanation, just that it happened.

 

Chrysler started using factory-equipment windage trays in their '68 (maybe '67) HP 383s and 440s and then offered the kit through their Direct Connection/Mopar Performance line of factory HP parts.  There can be a vortex of oil around the spinning crankshaft counterweights.  Oil not in the pan can't be lubricating the motor!  So the "tray" decreased that spinning vortex of oil.  Decreased horsepower loss due to that situation, too so more power to the rear wheels.

 

Moroso came out with a "scraper" that was a strip of metal which was fitted to clear the crankshaft counterweights as they spin, to get MORE of the oil from around the spinning crankshaft to drain back into the oil pan for re-circulation.  MORE horsepower found!  This would be "race only" item as oil splash not only helps lubricate the lower cylinder walls but ALSO the camshaft lobes (needed on flat tappet motors, but less so with roller valve lifters on cam-in-block engine designs.

 

I believe other engine brands also used windage trays, in varying forms, but didn't get the wide publicity (at the time) of using them in OEM production that Chrysler did.  Plus other engine parts vendors (as Moroso and others) also offered some, too.  No need for a windage tray and a "scraper" in the same engine, as far as I know.  Both serve the same purpose, just in different intensities.

 

As for a street motor in normal use, probably no real advantage per se as we normally wouldn't miss another 5-10 horsepower, but another 1/2mpg could be documented easily.  Plus a little sharper throttle response, possibly.  When the "Era of Nailhead" was winding down, that's when Chrysler made windage trays popular with racers.  There possibly are several engine design features (including stroke length, connecting rod length, width of the oil pan rails, other internal design areas).  With the Chevy LS engines, they found out that when they put small "windows" in the part of the cylinder bore which extended into the crankcase  windage decreased and more engine rpm was possible (due to decreasing "windage" issues). 

 

I understand EmTee's orientation of running the oil level a little low, yet some road course stock racers do just the opposite as a lot of the oil is pushed up the side of the crankcase in corners and such.  The alleged reason for Chevy's popular small block oil sump arrangement (rear sump) was that oil stacked up at the rear of the pan/block on acceleration (which their engines seemed to be good at) rather than use a front sump, more baffled oil pan design . . . but chassis design also plays a part in such things, too.

 

NTX5467

[NC-car-guy]

Interesting.  The 56 322 I have out of a century did NOT have one.  But the 55 I had out of a super DID!  Now I want to look and see if there are tapped holes in all the blocks or just that one.

[old-tank]

Early 55 engines had them; some late 55 engines did not.  No perceived difference in performance.

[Beemon]

Interesting. I'm going to have to drop the pan to replace the timing cover and check the timing chain some time before August, so if I find one before then maybe I'll try it out.

 

Matt, please report back if the holes are still there for the tray. 

[Guest]

The late 55s and 56 322s were at the end of the engineering evolutionary cycle for the 322. I've read about some of the changes in the service bulletins and shop manuals. I'm guessing if there was an advantage to eliminating the windage tray, it may have been the piston skirt & cylinder wall oiling as previously posted, but in most things investigated these days, especially politics, the old saying "follow the money" might be an even better clue as to the why. Bean counters, from what I've heard, fought with engineers at car companies often and won lots too! Might fall into the category, fix it till it breaks! Oh, I meant, if ain't broke....Lol! I know, I know, don't quit the old retired guy gig for a comedy career!

[Beemon]

If the advantage was to oil the piston skirts and cylinder wall, then it would only benefit the rear half of the engine since the front of the oil pan is too shallow to sling oil from the sump. I can't really wrap my head around that. Maybe if it were a center sump? My understanding is the windage tray is the same mounting depth as the front of the oil pan and is notched for the oil pump.

[NTX5467]

In DeLorean's book "On A Clear Day, You Can See General Motors", it's related of how in getting their final proposal for a new model in the 1960s ready for final financial approval, they went through and specified items for the car (tires, interior, etc.) that would last past the 2-3 year trade-in cycle, therefore making a used Pontiac worth more at that time (due to lack of needing things to freshen it up for resale) AND have it cost the same as the prior model.  They felt they were doing a good job, yet the Financial people wanted an additional  $25.00 (for example) "out" of the car's production cost.  SO, they had no alternative but to go back (this is happening in July or August just before production is scheduled to start a month or so later!).  Such "last minute" cuts could only be for things that would be easy to change . . . deletions of minor trim items, less expensive interior fabrics, a smaller STANDARD tire size, or deletion of things "not seen" in order to meet their financial mandates.  Key word is "standard" as the same things could become part of an extra-cost option package.

 

I'd observed that in one year, an interior "wore like iron", but in the next year's same model vehicle, the interiors had poor durability.  When talking in a long-time Chevy enthusiast, he noted that some years' cars had great things, to be followed by "less" in the next model year.  No doubt, that scenario played out in other GM vehicle lines, too.

 

It's somewhat common for a "shield" to be near the rear-mounted oil pump, but not a full windage tray per se.  I'd suspect, on rear sump oil pan situations, that it was to deflect rapid oil movements from acceleration or inclines, and delay massive amounts of oil being at the rear of the engine all at once.  Not necessary for operation, "not seen", and possibly deemed "not needed" by some, but it would not have been designed IF it was totally ineffective, I suspect.

 

That book, plus the similar Iacocca book, explained LOTS of things I'd seen or heard about in the automotive industry!

 

NTX5467 

[buick5563]

I have a bunch of trays that I didn't reinstall on my engines if you want one.

No, I'm not really mailing one....

There is no reason to add it. Like Willie said, they came on the early 55's (that I know of), which had the center oil fill tube and no valve cover breathers. 

[1953mack]

Buick's only reason:

 

 

Al Malachowski

BCA #8965

"500 Miles West of Flint"

 

[NTX5467]

Must have been some sludge in the valve cover issues?  OR it was too far to reach to add oil for some owners?

 

I found a SAE Transaction where GM was doing research on the optimal flow rate for PCV valves.  Their test vehicle (at least one) was a '61 Chevy 235 6-cyl in the GM Plant  Security fleet.  LOTS of low speed operation in that use!  When the PCV was installed, sludge accumulation was decreased.  When a second valve was installed, sludge formation decreased again.  But there was a limit to what was doable and that's what the ultimate flow rate was settled on.  Better than a road draft tube.  The 1967 Chevy V-8 PCVs were actually adapted to the prior road draft tube location.  Quite simple and effective!  At least until their next change in cast engine parts was justified.

 

I don't see any engineering reason that the oil baffle would help engine ventilation, BUT deleting it would help decrease the cost of the TSB change.

 

This is now, that was then . . .

 

NTX5467