By Don Nester
Chapman Report – May 1979

The modification of the Twin Cam oil pan is really a requirement for all Europa (and Elan) Twin Cams. Colin Chapman in all his wisdom endowed the TC Europa with cornering capabilities which cause the oil pump to starve in right hand corners. This, as you would expect, is very hard on the engine’s inners.

The best and most expensive (about $500) correction to this problem is to dry sump the engine. The second best method is to add baffling to the oil pan. Modified pans may be purchased locally from Twin Cam Enterprises (out of business, try Dave Bean, RD or JAE – editor) for about $75.

Being cheap and of the experimental type, I decided to modify my oil pan myself. Never having done this before, I carefully studied and sketched the Twin Cam Enterprises modified pan. Also, I studied what has been done with standard American cars (particularly high performance Chrysler products). I then sketched out my own solutions and began to worry if the baffling technique which I was to use would restrict the flow to the oil pump. After all, not being a hydraulic engineer, I questioned what the oil was really doing inside the sump. Well, after much concern and several sketches, I got out my welding torch and modified the sump. The sump has been back on my car for 8,000 miles, has caused no negative problems, and as far as I can tell, it has corrected the original problem of losing oil pressure on right hand turns. Here is my solution…

TWIN CAM OIL PAN BAFFLING

The single baffle in the center of the Twin Cam pan is insufficient to control oil starvation on right hand turns. The following modification is recommended to correct this problem.

1. Remove original baffle by drilling out spot welds and then reweld holes.
2. Decrease size of balance openings at either end of baffle.
3. Add trap door at back of pan which opens toward oil pick-up, and drill ½" holes in baffle to let oil flow through when door is open. (Note: Trap door must fit well and work freely)
4. Weld angle brackets to top of baffle to accept interval sump cover.
5. Refit baffle in pan (1/2" further away from oil pump), but do not weld into place.
6. Bend and shape 1/32" steel plate into sump cover as shown below, and fit with screws to top of baffle.
7. After carefully measuring, cut out the hole for oil pick-up to slide through and weld a 1" strip of steel on lower side of sump cover around hole for oil pick-up.
8. Refit in pan and with pencil, mark the position of the baffle on the bottom of the pan.
9. Disassemble baffle assembly and reweld baffle back into the pan. Then screw sump cover back on baffle. Mark pan for right hand sump cover supports, remove sump cover, weld on sump cover supports to pan, refit sump cover, drill and tap holes for screws, and screw into place.
10. Fit pan back on engine (use no gaskets and only four bolts) and then turn engine over to insure modified pan does not obstruct crankshaft (mine did). If it does, it well be the top edge of the sump cover and you will have to rebend it so it does not touch. Mark sump cover with dip stick by ramming dip stick down its receiving tube several times. Remove pan, drill hole for dip stick and rebend sump cover if necessary.
11. Refit pan back on engine.