Are you completely baffled?

To some readers this may seem OTT – and I understand that – but I have never felt confident that the oil pump will not, on occasion, be starved.   The earlier XPAG engines as fitted to the TC had, for some reason, the oil pick-up on the left side of the sump.  I suspected that this could result in temporary oil starvation – on hard left-hand bends, for example – so to avoid the possibility of this ever happening, I have fitted additional baffles to the sump.  Incidentally, I have read about oil starvation on road cars, so it’s not just limited to racing.

(I understand that later engines had the oil pick up centralised – which must have been done for a reason.)

In my sump, there is a small baffle to the front which, in the original design, was presumably intended to reduce forward oil surge under braking.  I have retained this but added further baffles, which I believe will help prevent starvation to the oil pick up and also reduce splash. 

Here the front baffle is removed and shows how my addition was first fixed.  The four substantial brackets provide a good surface area and are an interference fit with the sump walls. However, it didn’t stay like this as a design change was called for. 

During the rebuild of my TC I have endeavoured to make any modifications fully reversible and to that end I resisted the temptation to drill or weld the sump. 

At this early stage I had thought a small gap under my new baffle would be sufficient for oil equalisation but, again, as the project evolved, I had other ideas… 

In the following picture the small baffle has been returned to its normal position where it also serves to prevent the new one from climbing upwards. I understand later XPAG engines had an extended horizontal baffle, so my plan was to also add one; the aim being to reduce the amount of oil being splashed up.  Obviously, a certain amount of lubrication is required… but too much can inundate the bores and overwhelm the piston oil control rings.

First, I cut a suitable piece from plate steel and shaped it to fit the profile of the sump.  I then made two openings as shown and carefully measured and drilled 8 x 5mm holes. I then measured and drilled 8 more holes in 2 x ‘one way’ flaps that I made from some steel hinges.   I have chosen to secure the flaps to the vertical baffle with slot head screws and ’Nylock’ nuts – which I believe are capable of withstanding engine temperatures at sump level.   The flaps will move easily; with the oil holding them closed when needed (on left hand bends) and open in all other situations. 

A lip on the edge of the original horizontal baffle created a gap between it and my additional one.  I overcame that problem by repositioning the two front brackets (turned through 90 degrees) and using them with distance pieces to enable four bolts to hold it in place.

…  as shown in the photo, I used four small round distance pieces and the two brackets to enable all three baffles to be bolted together.

The last photo shows the sump with everything bolted in place. I deliberately left a gap at the side so sufficient oil can splash up to the bores. 

As I say, this may seem OTT for a road car… …but I enjoyed doing it.                                    Ray White

Ed’s note: For the benefit of some of our readers for whom English is not their first language, ‘OTT’ stands for “over the top”. You could say it means “more than is really necessary.”

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