Lotus Twin Cam Oil Pan Baffle

[LCRJ]

Hi All,
What would be the ideal baffle plate design for a 4-bolt oil pan?
I am interested in the Mountune one.
https://www.mountuneusa.com/Ford-Kent-Lotus-Twin-Cam-Oil-Pan-Baffle-Rope-Seal-p/1010-oc-ab.htm
In this case, should I still keep the originally attached plate (running horizontally)?
Or would it be more effective to have a wall around the center oil pickup?
https://initracing.co.uk/parts-for-sale/lotus-twin-cam-sump-baffle-kits/
Please let me know what you think.
Thank you. Hiro

[rgh0]

https://elantrikbits.com/gated-baffled-sump/

This is based on a design I develop from a description i got from an old twin cam racer many years ago. You will find posts that detail my design further or you can get the E-book from ElanTrilBits. Its been installed in many racing Twincams over the last 30 years and works.

The advantage of having a 120E block and 4 bolt pan is that you already have the centre pick up and do not need to relocate it like in later engines with the press in side pickup.

cheers
Rohan

[h20hamelan]

I believe some have said, a simple front-rear divider for spirited road is adequate.
Too bad there is not a windage tray (then you could overfill sump), under crank. Also, a oil pick-up bracket too
Add bacon and beer, divine.

[LCRJ]

Hi Rohan,
Thank you for the new information for me. I watched the video about the mechanism and it seems to be effective for lateral movement. What about the front and rear direction, there seems to be no original plate and no special mechanism?
I basically drive on the street, but occasionally on the track. The centre oil pick-up seems to be an advantage, but based on my experience I think I need a baffle plate that is more effective than the original. I would like to use a kit if one is available.
Kindest regards, Hiro

[rgh0]

Hi Hiro

The side swing baffle design has been shown to be adequate for both hard driven road cars on winding mountain roads as well as race cars. Conceptualy a 4 sided swing baffle design would help with fore / aft accelaration also but it does not appear to be needed in practice even in extreme racing situations. In practice the duration of high g acceleration and braking is much shorter than high g conering which is probably why it is not necessary.

The only kits I am aware off are like the ones you posted using fixed baffles and the effectiveness of these I dont know but i believe they would not work as effectively for long duration hard cornering compared to swing gates design. It should be easy to get some competent sheet metal shop to make up the swing baffle design from the E book if needed at a similalr price to buying a kit.

A alternative is to use an accumulator such as Accusump. I used this for a number of years before it was banned for my racing class with good effect before I installed the swing gate baffles I use now

cheers
Rohan

[mbell]

The only kits I am aware off are like the ones you posted using fixed baffles and the effectiveness of these I don't know

This thread had me wondering about the effectiveness of this solutions as I am likely pulling my standard sump in near future and might be good time to fit one. As a road car I think the swing baffle solution is a bit over the top (for my fab and driving skills) but the mountune one would be an option.

The question becomes does it ensure the oil pick up stays submerged in extended right hand corners. If you assume it does a good job of prevent leakage out of the sump bowl, then the question is whether there is enough oil in the bowl to keep the pickup covered.

My estimate is the sump bowl holds somewhere between 2.5L and 3.0L of oil. So my guess is probably going to need 2.0-2.5L of oil in to bowl for pickup to stay submerged, that might be an over estimate thou. My experience is that my car takes about 3.75L of oil. The oil filter probably contains 0.5L of oil. So 3.25L left in sump with engine off. When running a certain amount of oil will be distributed around the engine, this will probably vary quite bit with engine revs etc. I've no idea how much that would be, but throw out 1.0L as a number.

That would mean I'd probably have 2.25l in the sump bowl when running, which would give a good chance of such a fixed baffle working.

Of course this are all guess numbers and more measuring would be required to confirm. Also in a race engine the high rev running is likely to trigger more oil to be spread around the engine rather than in the sump. So a swing baffle setup would likely be better.

[mbell]

I've now got the sump (6 bolt) of my car, so did some rough measurements yesterday.

The standard sump baffle is ~2.5" high, it takes ~2.5L of fluid to be level with it. So I think that these type of baffle are likely to work ok by prevent oil rising out of the left hand side of the sump under cornering forces, if you can keep 2L+ in the sump for moderate use.

However my rough measurements suggests that filling the sump to the max mark on my dipstick would means between 2.0 and 2.5L oil in the sump when measured. At these kinds of levels I guess there might not be enough oil in the sump when running, especially at high revs for extended periods for the baffle system to be certain to work. It likely better than no baffle thou.

Also worth saying that my measurement suggest you can have at least 3.5L oil in the sump without it being in contact with the crank. So there is plenty room for some more oil. My dip stick has also been marked by someone ~1" higher than max, which might be indication of better oil level or correction for wrong dipstick/tube being used.

[joe7]

RD sells baffle kits. One warning, from experience, drill a hole in the baffle for the dip stick before you install the sump. Regarding the dip stick, just put in the required amount of oil and see where it registers on the stick.

[LCRJ]

Hi mbell,
Thank you for the information. It is very helpful.
I see that there are early and late dipsticks. The later one has a different indication position and the oil amount is increased (4.25L, including in the oil filter). I think a top plate is absolutely necessary for both 4-bolt and 6-bolt sumps. Still, I have experienced the warning light coming on at the track and on steep corners on mountain passes (although it is possible that I was a little low on oil). I think the top plate flap on the montune is an interesting mechanism, but I wonder if it is that necessary.
Hiro