Posted By: Hot 340
What's the verdict on windage trays? - 10/28/12 11:34 PM
Power robber or adder? Ive heard both...
What's the verdict on windage trays?
Posted By: topside
Re: What's the verdict on windage trays? - 10/28/12 11:41 PM
I always refer to Smokey Yunick putting a window in an oil pan & filming the rotating assy picking up the oil and creating basically a rope around itself, which then aerated the oil. That was in the early '60s, IIRC.
Most trays don't allow enough drain-back, so either the one-way mesh or cutting additional one-way slots in them are good ideas.
Another way to prevent windage is a deep pan with the oil a few inches away from the crank, but I still run a tray on my deep-sump motors.
Most trays don't allow enough drain-back, so either the one-way mesh or cutting additional one-way slots in them are good ideas.
Another way to prevent windage is a deep pan with the oil a few inches away from the crank, but I still run a tray on my deep-sump motors.
Posted By: gch
Re: What's the verdict on windage trays? - 10/28/12 11:47 PM
Crank scraper FTW
Posted By: CompWedgeEngines
Re: What's the verdict on windage trays? - 10/28/12 11:47 PM
A well designed oil pan is better.
Posted By: tubtar
Re: What's the verdict on windage trays? - 10/28/12 11:47 PM
A directional tray is superior for sure.
I had one in a big Ford that I took to Nordic Ware , a manufacturer of cooking pots , pans and stuff and had them teflon coat it for me.
The guy who worked there thought it was cool and did it for nothing.
I don't know exactly what difference it made , but it sure shed oil in a hurry , which had to help drain back.
And the flat slots on the tray itself , I made them louver like in the direction of rotation to help both catching oil and draining back.
I had one in a big Ford that I took to Nordic Ware , a manufacturer of cooking pots , pans and stuff and had them teflon coat it for me.
The guy who worked there thought it was cool and did it for nothing.
I don't know exactly what difference it made , but it sure shed oil in a hurry , which had to help drain back.
And the flat slots on the tray itself , I made them louver like in the direction of rotation to help both catching oil and draining back.
Posted By: Locomotion
Re: What's the verdict on windage trays? - 10/28/12 11:49 PM
There will always be people on both sides of the fence and designs vary as well. But in the Stock classes, most small block racers do not use a tray. Not sure about big blocks, but they are somewhat different with "skirted" blocks.
Personally, I use a double-sided scraper. I always felt that an OEM style tray can actually trap too much oil. For as long as I remember, I always heard that the "windows" in the trays need to be opened up. Basically bending open the flaps more for drainage. I believe screens are better than trays because of the drainage area, but scrapers actually "scrape" the oil from around the crank to keep it from staying wrapped around it. A properly designed scraper and tray/screen can offer the most oil control. But it gets complicated and expensive.
More info on scrapers here:
Crank scrapers
Personally, I use a double-sided scraper. I always felt that an OEM style tray can actually trap too much oil. For as long as I remember, I always heard that the "windows" in the trays need to be opened up. Basically bending open the flaps more for drainage. I believe screens are better than trays because of the drainage area, but scrapers actually "scrape" the oil from around the crank to keep it from staying wrapped around it. A properly designed scraper and tray/screen can offer the most oil control. But it gets complicated and expensive.
More info on scrapers here:
Crank scrapers
Posted By: 340B5
Re: What's the verdict on windage trays? - 10/29/12 12:26 AM
I used the factory windage tray for a frame for the screen.
The screen is from Canton.
The screen is from Canton.
Posted By: Chris2581
Re: What's the verdict on windage trays? - 10/29/12 12:37 AM
I agree with Myron (Locomotion) about this. FWIW..I decided NOT to use a windage tray on my 440,instead used a crank scraper from the company in Locomotions post.In the past,a windage tray was always used.I have found that the scraper works and the oil pressure is rock steady.I'm not going to drop the pan and install a windage tray for a comparison,but I feel the scraper is doing it's job very well.
Posted By: rowin4
Re: What's the verdict on windage trays? - 10/29/12 12:37 AM
With the typical factory windage tray it would seem to limit the amount of oil pushed up into the rear of the rotating assembly on a hard launch, also to the front on hard braking. The screen system I would think would drop the oil out faster during the run for more oil return into the pan. How much power do you think is lost during the launch with the rotating assembly fighting all that oil? 
Posted By: Cab_Burge
Re: What's the verdict on windage trays? - 10/29/12 12:54 AM
It depnds on which Mopar motor, BB or SB. No windage tray on SB,yes to a good one on BB 
I make and use my own crankshaft scrapers on both
I make and use my own crankshaft scrapers on both
Posted By: Hot 340
Re: What's the verdict on windage trays? - 10/29/12 12:59 AM
Quote:This is my thinking as well and why Im considering it for use on my low-budget smallblock...Cab, why do you say no on a sb?
How much power do you think is lost during the launch with the rotating assembly fighting all that oil?
Posted By: Cab_Burge
Re: What's the verdict on windage trays? - 10/29/12 01:17 AM
I use to run NHRA stock, some of the fastest NHRA SB engine builders and racer said to not use the stock windage tray in the SB, I was dumb enough to not trust them so I did a A,B,A back to back teston a customers 1971 340 on a DTS engine dyno to see if they where right on the stock 340 windage tray 
It lost HP and torque with the tray in it above 4500 RPM 
Another freind of mine that has set several NHRA class records did use the one way oil screen on a stock cut out windage tary like on the picture on here, that works 
It lost HP and torque with the tray in it above 4500 RPM Another freind of mine that has set several NHRA class records did use the one way oil screen on a stock cut out windage tary like on the picture on here, that works
Posted By: Locomotion
Re: What's the verdict on windage trays? - 10/29/12 02:13 AM
Quote:
With the typical factory windage tray it would seem to limit the amount of oil pushed up into the rear of the rotating assembly on a hard launch, also to the front on hard braking. The screen system I would think would drop the oil out faster during the run for more oil return into the pan. How much power do you think is lost during the launch with the rotating assembly fighting all that oil?
I don't think that trays, especially on a small block, are tight-fitting enough to keep much oil that sloshes back from making its way above the tray anyway. The sump should be baffled to help keep oil there contained and the oil level drops a bit as rpm come up because it's getting pumped. The back "ledge" however, is somewhat an oil trap on accelleration.
One also has to consider the fact that oil is also draining down from the heads and cam in addition to "leaking" out from the rod and main bearings. Without proper drainage, a tray can literally "catch" that oil and keep it caught up in the windage/vortex. That's why you hear about builders emphasizing proper clearances and oil restrictions to the rockers. The trick is to know how much to restrict so you don't starve anything up top. Every little bit helps. It's just a matter of how important a few more HP is and what you are willing to gamble - just like draining some engine oil or differential fluid for a heads-up run for a couple of hundredths in ET.
Posted By: gregsdart
Re: What's the verdict on windage trays? - 10/29/12 01:31 PM
Quote:
There will always be people on both sides of the fence and designs vary as well. But in the Stock classes, most small block racers do not use a tray. Not sure about big blocks, but they are somewhat different with "skirted" blocks.
Personally, I use a double-sided scraper. I always felt that an OEM style tray can actually trap too much oil. For as long as I remember, I always heard that the "windows" in the trays need to be opened up. Basically bending open the flaps more for drainage. I believe screens are better than trays because of the drainage area, but scrapers actually "scrape" the oil from around the crank to keep it from staying wrapped around it. A properly designed scraper and tray/screen can offer the most oil control. But it gets complicated and expensive.
More info on scrapers here:
Crank scrapers
Look at the environment changes from when a windage tray was designed to what we want to use them in.
Loose clearances add a lot of oil flow, rpm is much higher than stock creating a storm in the crank case that probably doubles the windage in the crank case at the minimum and goes through the roof on a max stroked, tightly confined space like a low deck stroker, which is also seeing the huge increase in piston displacement of air in the crank case.
My own experiences have shown that a b motor 499 doesn't like a screen/dragster pan at all, a side bucket pan with a big kickout helped a lot and reduced the tremendous amount of oil being forced out through the vacuum pump or breathers, and that a scraper combined with the side bucket pan and screen not only kept the oil out of the puke tank of the vacuum pump but stopped the problem I had with losing oil pressure when braking hard. So each increase in windage (rpm, stroke)and oil volume (big bearing clearances) adds to the problem.
Posted By: Kevin_Johnson
Re: What's the verdict on windage trays? - 10/29/12 02:58 PM
Quote:
I use to run NHRA stock, some of the fastest NHRA SB engine builders and racer said to not use the stock windage tray in the SB, I was dumb enough to not trust them so I did a A,B,A back to back teston a customers 1971 340 on a DTS engine dyno to see if they where right on the stock 340 windage tray
My guess is that 4-bolt caps were being used (?) with the stock tray. At high rpms the bay to bay pumping exchange is limited and that will cost hp.
It gets complicated.
One of Smokey's Nascar 2-bolt main blocks has rounded main caps for that reason. You see that on many modern engines.
Windage trays have diametrically opposed technical requirements which are typically best met with multiple layer trays.
Posted By: sixpackbee
Re: What's the verdict on windage trays? - 10/29/12 05:32 PM
No question on a small block no tray. Big block/Hemi use a tray. In either case use a well designed scrapper. Thats the Clifts notes version.
Posted By: Kevin_Johnson
Re: What's the verdict on windage trays? - 10/29/12 07:45 PM
I think the stock 340 tray was developed as an all around part: road racing and drag. Not too many outfits have articulated dynos where they can tilt the engine 30, 40 degrees front to back or side to side.
There is an SAE paper from Mercedes (750051) from when they were developing their V8 that shows the aeration levels at different angles. They chose a scraper array across the rear floor of the pan, angled so that a vector would return the oil to the sump. Ford also used this tech (and Porsche). For high performance Mercedes installed a dry sump system for its street V8 engines (very limited numbers).
I read some of the remarks from contributors here on years back threads. Adding sump baffles is a good idea -- guess what -- many are technically windage trays as well. Look at the stock SBC setup with surge baffles and a secondary plate over the sump -- that is a dual level tray system. There are technically complex factory wetsumps like the Nissan RB26DETT that have triple level trays.
I just looked at a 360 core out back -- rounded two bolt caps. Surprise, surprise, surprise as Gomer would say.
There is an SAE paper from Mercedes (750051) from when they were developing their V8 that shows the aeration levels at different angles. They chose a scraper array across the rear floor of the pan, angled so that a vector would return the oil to the sump. Ford also used this tech (and Porsche). For high performance Mercedes installed a dry sump system for its street V8 engines (very limited numbers).
I read some of the remarks from contributors here on years back threads. Adding sump baffles is a good idea -- guess what -- many are technically windage trays as well. Look at the stock SBC setup with surge baffles and a secondary plate over the sump -- that is a dual level tray system. There are technically complex factory wetsumps like the Nissan RB26DETT that have triple level trays.
I just looked at a 360 core out back -- rounded two bolt caps. Surprise, surprise, surprise as Gomer would say.
Posted By: Crizila
Re: What's the verdict on windage trays? - 10/30/12 03:19 AM
I run a stock tray ( slots opened up ) with an 8 qt Milodon baffled pan runing 7 qts in it.