DIY Oil Pan Baffle - Car Craft Magazine

It's puzzling, really. We all know the importance of maintaining constant lubrication under high-performance driving conditions, yet, far too often when building a performance street mill, we take that cafeteria-tray factory sump and just button up the bottom end.

Add sticky meats, huge brakes, slot-car suspension, and that new-found 200 extra horsepower, and oil will slosh around the bottom end like water in a bilge. Dig deep in the throttle and your oil does its best to splash-lubricate the rear crank counterweight, while the pickup screen sucks air. Hammer the brakes, and your 20W-50 does a mini tsunami for the front cover. Angle into your line as you slice up the local canyon, and your precious lubricant will angle up the banks of that V-8.

At the top we have the typical small-block Mopar open sump-absolutely nothing but a nice smooth ski run off the sump floor in any direction. At the bottom is the Hemi/ big-block high-performance sump. While very basic in its horizontal baffling, even this is a tremendous help in oil control.
At the top we have the typical small-block Mopar open sump-absolutely nothing but a nice s
The first step in designing the baffle is determining the routing and placement of the oil pump pick-up tube. Bolt the pan to a bare block with the oil pump and pick-up in position, and reach through a cylinder bore to trace the outline of the pick-up on the sump floor with a felt marker. Make a second set of marks along the sidewall of the pan to indicate the height of the pick-up tube.
The first step in designing the baffle is determining the routing and placement of the oil
The two sets of marks give a three-dimensional map of the pick-up tube's location.

The above scenarios are common in performance street machines. With a stock open-bottomed sump, performance levels need not reach outrageous levels to compromise the lubrication system. Could be you're not even hip to what's going on while the oil gauge does its quick dip to zero, but your bearings will feel the pain. What if your engine doesn't have a wide range of special purpose road racing pans available from the aftermarket, and you're scared that scrapping a drag race deep-sump over potholes and speed bumps may cost you oil pressure faster than even that old open-sump pan? Aftermarket pans can be found for virtually any need on a small-block Chevy, yet, for other applications you may be on your own.

Our own pan plan came into being in trying to improve the oil control in a stock small-block Mopar sump. Hard braking was the cause of splish, splash, bearing rash, with the final outcome of a spun rod bearing. Although high-performance big-block Mopar engines came with rudimentary horizontal baffling, Mopar small-blocks, even the mighty 340, used a pedestrian open sump. While drag and wide oval-track racing pans can be had for this engine, we modified the stock pan because we knew it would fit, clear the steering linkages, and be well protected against bashes in a street application, tucked up behind the K-member. Finally, with some spare 0.050-inch-thick sheetmetal, we were able to cobble a performance pan in a fun-filled afternoon of fabrication, without ever having to pull out the wallet.

Low-tech corrugated cardboard is used to make the baffle pattern. Mark and cut the board to form a lid over the entire sump, with a turned-up flange running the length along each side. Mimicing the stock big-block baffle, the front edge of our baffle sits flush just below the floor at the front, while overlapping the floor at the rear.
Low-tech corrugated cardboard is used to make the baffle pattern. Mark and cut the board t
Mark an outline for the baffle's center opening. Our design included baffling front and rear, as well as laterally to each side, with a generous radius at each corner. Follow the form of the sump shape and use the marks and guidelines to make accommodations for the pick-up tube.
Mark an outline for the baffle's center opening. Our design included baffling front and re
Cut out and tape the cardboard baffle into position, and bolt the pan up for a trial fit. A clearance check was also made with a stock windage tray installed.
Cut out and tape the cardboard baffle into position, and bolt the pan up for a trial fit.

This view through the number six cylinder shows that we were a bit too generous with space around the pick-up tube. Modify the template with masking tape to make any changes.
This view through the number six cylinder shows that we were a bit too generous with space
Once satisfied with the template's fit, mark the outline onto the sheetmetal stock. We used an uncoated 0.050-inch-thick mild steel sheet.
Once satisfied with the template's fit, mark the outline onto the sheetmetal stock. We use
In mass production, a finished baffle is formed by a single pass of a stamping press. To make ours, we barbarically hacked the entire form, inside and out, with this high-speed die grinder and cut-off wheel, beautifully finishing the piece with hand files. A jigsaw, bandsaw, or plasma cutter would have been more civilized.
In mass production, a finished baffle is formed by a single pass of a stamping press. To m

Turn up the flanged edges. If you have access to a sheetmetal brake, by all means, use it. A simple brake can be made with a couple lengths of square tubing clamped as shown and a hammer. Crude but effective, this set-up yields gorgeous bends. Support the vise grips while striking.
Turn up the flanged edges. If you have access to a sheetmetal brake, by all means, use it.
To aid in oil control, dramatically increase the baffle's stiffness (the 0.050-inch-thick metal is already very stiff); the inner edge of the baffle was turned down 90 degrees, except for the pick-up tube slot, which was left flat for close clearance. The turned-down lip is formed by starting the edge all around with vise grips (a little at a time), and then hammering the flange in against a dolly clamped in a vise. The finished product looks machine formed.
To aid in oil control, dramatically increase the baffle's stiffness (the 0.050-inch-thick
Slide the baffle into position in the pan. It should fit snugly. Adjust the shape as required for a good fit. Ours dropped right in, needing no further work.
Slide the baffle into position in the pan. It should fit snugly. Adjust the shape as requi

With the baffle in position, bolt the pan in place for a trial fit. Our pan lined up perfectly. Check for interference and line up and adjust as required. Now mark the location for the dipstick hole, which, in our application, needed to be drilled into the baffle.
With the baffle in position, bolt the pan in place for a trial fit. Our pan lined up perfe
The dipstick hole location is marked at the upper left of the baffle. At the trailing edge, where the baffle overlaps the floor, it's marked for two drainback slots. At the front, the baffle doesn't overlap the floor, sitting slightly down off the front wall. The downward slope and irregular joint at the front edge allow adequate drainback here.
The dipstick hole location is marked at the upper left of the baffle. At the trailing edge
The drainback slots are easily punched in with a scrap of a flat bar with a radiused nose. Punch between two supports as shown.
The drainback slots are easily punched in with a scrap of a flat bar with a radiused nose.

The dipstick hole was drilled to 9/16-inch and the hole was enlarged and swaged-in with a socket, while the O.D. was backed up with a larger socket.
The dipstick hole was drilled to 9/16-inch and the hole was enlarged and swaged-in with a
After a final trial fit, the baffle was welded in position. We gas-welded ours, clamping each spot as we went around. A MIG, TIG, spot welder or brazing could also be used.
After a final trial fit, the baffle was welded in position. We gas-welded ours, clamping e
The finished baffle captures more than 3 1/2 quarts of precious oil and adds a touch of elegance to the sump's otherwise drab decor.
The finished baffle captures more than 3 1/2 quarts of precious oil and adds a touch of el