Winged Sump

[erictharg]

I'm with Splat on the choice of sealant. A quality non hardening jointing compound is what you need. Try not to use RTV / silicone. Blue Hylomar is my preference too. Hemetite Gold also used to be similar. RTV is fine for emergencies or when you don't have a gasket. For it to work properly (and not end up where you might not want it) you need to very controlled in application and assembly.

[Westfield 129]

I use RTV (Blue Hylomar works, too) only on the pan to hold the gasket. The gasket should seal just fine on the machined flat surface of the block. I have done numerous engines with this, and have no problems at all in removing the pan. The pan will come off easily once the bolts are removed. Just give it a slight tap with a mallet to free the end seals.

Another excellent sealant is Hondabond (or Yamabond). I have used this on at least a dozen engines. Again, only on the pan side. This also works well on the front cover to retain the gasket. This is available at your local Honda or Yamaha motorcycle dealer.

If I think that I may have to remove the part, say a front cover, for adjustment, I will put a little Dow 4 silicone grease on the gasket face against the machined block face. This will ensure sealing, but also ensure that the gasket will easily come loose when I need to do an adjustment. I also use Dow 4 on oil filter seals to prevent sticking, and on rubber seals or O rings to ensure seating.

RTV/ Blue Hylomar still works best at the joint between the pan gasket and the end seals.

Note that there are lots of RTVs with different qualities. I use those that fit the particular application. The best are made by Dow for the aerospace industry, and are available at aircraft supply stores.

[erictharg]

I don't disagree with any of that Jan. Using RTV to hold the gasket to the pan makes sense, and you can let it semi set before assembly thus controlling how much oozes out! I've just seen so many horrors where RTV has been used for everything and has got everywhere! But it does have it's place in our toolkit.
For anyone contemplating a sump replacement job you might also want to seek out the gasket kit that uses the moulded plastic end seals (fit over the bearing caps) instead of the original cork items. They are a big improvement, and to some extent re-useable if pushed.

[adamwilkinson]

interesting, we couldnt get the plastic/rubber ones to seal yet have no issues with cork

[Westfield 129]

Ah yes, I forgot to mention to stay away from the cork seals. They don't have much of a shelf life (if you have an old set, they may already be hard prior to installing them), and don't seal nearly as well as the plastic ones.

Payen gasket sets (made by Federal Mogul, a company known for making high quality OEM components) are quite good, and include the plastic end seals. The plastic seals also work well if you have to remove the pan, then re install it.

[jonclancy]

Arrrgh - lost post.

OK, here it is again (but less eloquent and entertaining... probably).

I've been discussing the sump-mods offline, but the urgency for replacement receded due to the success of my JB Weld/Smoothrite repair prior to the recent Hullavington track day. I note that Peter May Engineering supply a baffled sump for £57 (incl VAT/Exchange), and will contact them to ask if it is shortened on any way and what style of baffles are employed.

Here are my current thoughts - please feel free to chip in any tips. I know that modding A Series sumps is a well-known procedure, but I have been unable to contact racer I saw producing these items on the MG forums (a while ago - I believe he's out of the Midget scene now).

My plan is to use my spare (in bits) block, crank, conrods etc to work out the heights. I was going to rest the crank in the inverted block and bolt a conrod on. Then I’ll be able to measure exactly the lowest point of rotation. Then add a little leeway to that. That’ll be the clearance height for the windage tray.

I’ll borrow the dipstick and tube from my spare engine and confirm what difference there is between the “full” oil level and the lowest level of the crank rotation. This’ll give us an insight into the leeway given by the BMC engineers for the oil pick up pipe in the sump and the crank rotating into the sump oil. From there, we’ll be able to decide how much to lose from the sump - I was thinking a simple "cut'n'shut" process to maintain the strength of the sump base pressing and the top flange. The height of the removed material will give us the sump volume lost and also whether any surgery will be required for the oil pick up pipe and the bottom of the dipstick.

The lost volume can be recovered by sump-wings (or wing – like the RS2000 sump), or by fitting an oil cooler. As we said, the dry-sump option isn’t - it's just too expensive to be used on a standard engine (in a WF chassis with no undertray)! I have a feeling that trap-door baffles may be a bit pricey, but swaged holes would be a reasonable compromise.

There are two of us interested in these sumps now. Any other takers? Could be a WER collaborative design and limited production run. Also, IIRC, there were some baffled sumps on show at Stoneleigh. I can't make it, but if any of you guys see any while you're there, please could you get pics and prices? An off the shelf solution might be an easier option for the same outlay.

[erictharg]

Jon - I run the Peter May sump in my racer. It is externally standard so does not help ground clearance at all. It does have an internal baffle that surrounds the oil pick up and to date seems to work well, at least for me. I keep meaning to run an oil pressure light as well as the gauge to see if there is any momentary loss of pressure under hard braking but have not to date. Most of Peter's stuff has been proven on racing Midgets and does what it is supposed to.

[Westfield 129]

The A series sump doesn't need much. The pickup has to have a little wall around it to keep the oil pooled there. Doors are not really necessary. There is already a big baffle in the pan to stop fore/aft surge.

It is possible to build a winged pan, but you will need to put doors in it, and this becomes complicated. There is a company that makes one here, "Winner's Circle", but it costs nearly $1,500, if they have someone to make it... Lots of welding. Trap doors. Expensive and hard to make. However, I can get one and copy it if anyone is interested. It still takes a stock pan to build off of in exchange.

Peter May stuff is always pretty good, and their pan is pretty simple as well. It is much like the pan from US supplier "Sports and Imports". The Sports and Imports pan is relatively inexpensive, at about $350, but you need to send a pan so that it can be modified. They can cut down your current pan for ground clearance.

The easiest thing to do is to reduce the sump height by about half an inch. This wont change things much, and you can run the normal amount of oil in it without having problems with crank shaft windage. I bet that Peter May could supply his pan with that mod for you.

The other thing that is pretty common is to run a little more oil in the pan if you worry about unporting the pickup. Note that when running the engine hard, the pan is not full, as the oil is in the head and other areas, draining back slowly to the pan. This means that there is no windage problem or oil foaming at high RPM.

Also, I have yet to record a pressure drop when cornering at the track on the vintage tires, or my very sticky street 185/70/13s.

Note: Oil pressure lights are always way too late in recording pressure drops. Gauges work better, which is why we put gauges into the cars and don't rely on the lights.

My own experience is that if the ride height is too low, the pan gets dinged. I run a 5.25" front ride height with the driver in the car (the 15" wheels and 4.50 tires account for the extra .25"). This generally keeps the pan from hitting anything. The car rides better and handles better as well when it has some suspension travel in front (and in the rear too).

[jonclancy]

After a Cotswolds razzle out with Mooch, I decided to spend a while with my spare engine parts looking at this project.

A couple of thoughts first:

The US-supplied sumps are pricey. Well out of our league and I think I'm in the wrong job if I can sell a simple baffled sump for 350USD exchange. Peter May Eng replied to my quesries with lightening speed and confirmed that their more reasonably priced sump is not shortened and contains solid baffles. If I was a Midget driver, I think I'd just fit one of theirs. But we need to increase our clearance.

WRT ride heights, most of us are running 13" rims, so don't have the extra clearance that 15" wheels could offer. My car was set up correctly and handles well on road and track(day) - but could, of course, enjoy the period handling enhancement of crossplies/skinnier tyres.

Topic related, a bit - warning lights. I can entirely see the benefit of a FBRL attention-getter while racing. No doubt in my mind at all about that. As we all know, digital gauges (i.e. numbers) are a pain to process. That's why we like analogue needles. You can spot a trend very quickly. But, a FBRL attention-getter, in conjunction with a gauge, is what I understand most racers use. And so would I. I can't see that a FBRL is any slower to convey information than a gauge. Thinking about it in more depth, it would not be beyond the wit of man to chuck some circuitry off the RPM feed that arms the FBRL at a certain RPM and disarms it at idle or whatever.

Anyway, I digress. Here's the results from yesterday's playtime.

I built up my parts block using paper bearings. I took some photos to hopefully illustrate the measurements.

Here's a link to the album:

http://s94.photobucket.com/user/jonclan ... t=3&page=1

In short, Eric Barcham and his team gave us 2mm clearance from the internal bottom of the sump to the mesh filter on the oil pick up, and a crank to oil (max level) clearance of 40mm.

Can this sump be shortened - yes, of course, but it will require a mod to the oil pick up pipe as well as the sump itself.

My measurements are, in the main, referenced to the block face.

Dipstick tube length = 28mm (to allow measurement of max, min marks and dipstick length wrt the internal parts).
Max Mark = 110mm from block face.
Min Mark = 127mm from block face.
Dipstick end = 146mm from block face.

Crank High Point = 70mm from block face.

Pick up pipe filter mesh "bowl" top = 165mm from block face.
Pick up filter bottom edge = 120mm from block face. As you can see, running on MIN oil level will expose some of the oil pick up filter.

End of pick up pipe to filter "bowl" base-plate = 38mm.

Finally the sump itself:

External height from bast to flange face (to block) = 167mm
Internal height = 163mm

It's not 4mm thick material, so there is probably the "dent effect" in my measurement of this. The internal measurement is controlling, though.

How's that for a starter?

[Westfield 129]

Ride height at the front should be 5" with the driver in the seat. The 15" wheels can add .25", or not. Depends on how you do your setup. I leave the extra .25" in there as it doesn't seem to bother the handling (or my lap time), and helps with the ride and ground clearance. One could run the car lower, as it is adjustable, but there is little suspension travel available, especially in the rear. I also run softer spring rates. It handles better when the suspension is working, and not on the bump stops.

Here, in the land of $100/hr labor, $350 (£225) for a race pan with baffles and a modified pickup, along with a fitting for an oil temp gauge, is not bad at all. It's a complete assembly. And it comes cad plated and ready for installation. The pan is actually much like the excellent Peter May design. Of course, the shipping may make it a little more expensive, but good oil pans are not cheap. As I said, the best winged pans, shortened to your specifications, with trap doors, cost the better part of £1000. I am pretty sure I could make them for about £500, but I still need an exchange pan, and enough orders to make it worth while. Good TIG welding techs are expensive, and there is a lot of metal working involved.

The interesting thing about the standard pans is that the sump is pretty narrow. So the problem is not cornering, but rather braking. The standard baffle is positioned to mitigate fore/aft surge of the lubricant. Since the W11 doesn't brake that hard, especially on the narrow bias plys, the value of the modified baffled pan is questionable. Since I run a little more oil, I have never had a pressure loss, and continue to run a stock pan. For an SCCA racer running wide slicks and bigger brakes, I can see how that pan would be necessary.

As for a business, well, maybe you would make 6 to 10 per year. Not much money for quite a bit of labor, cleaning the pans, hammering out dents and patching, breaking out the baffle, installing a new one, then modifying the pickup, and sending everything out for plating.

As an aside, building a good 1380 engine costs about $5000 including the induction (weber and maniflow intake), light alloy flywheel, Longman head and roller rockers, but not the trick sump. That's if you get good pricing. You can save a little if you build it yourself, but there is still that $1100~1400 in machine work... I built one or two a year for friends. I am not getting rich doing it, but it is fun.

A couple of things: If you shorten the sump, the dipstick tube doesn't have to be changed at all, but you might have to cut the tip of the dip stick. As for the markings, they would not change as the max oil level would still be the same (but the quantity might not, with a shortened pan). While the 40 mm crank clearance might be important when the engine is stopped, the oil level is substantially lower when racing. You can run more oil, if you want, along with a cooler, to increase your capacity. The baffles might not be important at all if you can't pull a full G deceleration. I maybe can do that on the sticky, wide 13s, but not on the narrow bias ply race tires.

With the ground clearance limit being the chassis, my own pair of W11s do not have much sump below the frame. Less than 1/4". I would love to shorten a pan (and I am going to, as I have three spares). I am thinking about 1/2", and just flattening the pickup, while adding a single baffle to keep the oil from sloshing back. Actually, the baffle might just be over kill. the standard one might be just fine.

My experience with warning lights is that something breaks, and then the light comes on. Surges in oil pressure have to be pretty severe before there is an indication. I understand why they are used, and I admit to using them, but the value is questionable. So the light goes on, indicating that the engine needs a new crank... The one time that an oil line failed at the oil cooler, I FIRST noticed a slight deterioration in handling as my tires were being lubricated by the engine oil, and some trailing smoke. I also noticed that the cars behind me had all gone off the track (I was leading at the time), way before the oil pressure dropped (it hadn't), or the master warning light went on. I pulled off line, shut it off, and my engine, with 3 quarts of it's 6 remaining, was fine. If I had noticed it when the light went on, it would have been too late for the 5 liter V8 that was turning 7000 RPM. It would have been a "replace engine" warning light. Anyway, the experience led me to change slightly my pre race and post race inspections of the car to prevent such a problem in the future.