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Sump queries ( picture heavy)
omega 24 v6 - 8/8/10 at 05:24 PM

Ok so here we go again.
In a bid to NOT spend around £300 on an SBD QED set up I am still struggling with oil surge under prolonged heavy breaking ( even sudden braking at give way sign can show a pressure drop).
I have found these pictures on the net and surely after building a car I can get round the problem. here is a pic of the sbd type sump.


And pickup pipe



And here is my current( based on memory of the sbd unit) not working setup.
My thoughts are the following
1 Is my baffle plate to high ( allowing air space underneath.
2 Is the oil not getting back quick enough from the front block drains(or running forward on the top of the baffle plate under braking)
3 Is the pickup pipe/strainer just not flat enough or big enough.
4 Should I lower the baffle plate or gate the cross baffle or buy a sbd pickup pipe ( reasonable price IMHO)

My 100mm deep sump with cross baffle

Description
Description


with 5 ltrs in it

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My baffle plate which has battle scars from 2 previous attempts at baffling it so don't laugh

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my pickup pipe.


Werner Van Loock - 8/8/10 at 06:07 PM

why do you have a baffle across the bottom of the sump, this way there needs to be a lot of oil before it goes over there, while you need it at the other side.

The sbd sump doesn't have that baffle, only connected to the baffle plate, but i'm sure it won't block off a full section like yours does as theirs is hanging and yours is standing up.

my raw sump for the 4age has trap doors that only open 1 way (ie to let oil in, not out)


MakeEverything - 8/8/10 at 06:12 PM

Can you make the sump shorter and wider, which would make it more like its original transverse orientation?

I forget what they are called now, but ive seen a few that have been widened with "Blocked off" bits in the end to stop the oil moving too far forward.


snapper - 8/8/10 at 08:12 PM

You need the sump gated, flaps that only open to let the oil in but are forced closed as the oil tries to get out.
The gate on the opposite side to the escaping oil opens to let as much oil in as the engine needs.


omega 24 v6 - 8/8/10 at 08:17 PM

Mmm I realise what you are saying about the one fixed across the sump ( seemed like a good idea at the time. The cross ones on the sbd may or may not touch the bottom of the sump pan though (wish I new how much clearance they had).
I have seen these used on oval racing hotrods and they seem to work OK. i just cant seem to wotk out why I cannot get it right. It looks to be relatively simple in that photograph.


snapper - 8/8/10 at 08:32 PM

http://www.google.co.uk/m/search?oe=UTF-8&client=safari&q=sump+baffles&hl=en&site=images&ei=nxNfTNjoGYaSjAfAxYMn&ved=0CBgQsAQw Aw#i=7

Link to photo or google sump baffles and go to images


Canada EH! - 8/8/10 at 08:46 PM

Oval track and road are completely different. I can only describe what you need, a diamond shaped box around the pickup with flapper doors facing in toward the pickup.
The flapper doors can be made with small pieces of 16 guage and strip hinge material.
The idea is to have the oil enter the box from both back shutters when braking, but the oil can not get out the front of the box as the other shutters will be closed.
The reason for the diamond shaped box is that no matter what the car is doing braking, cornering, or accelerating out of a corner there is always oil being forced into the box by G forces.
The box should be made large enough to hold a litre of oil to prevent starvation. We used this system in CanAm cars before dry sump systems were availabel, dry sump is the true answer.


mark chandler - 8/8/10 at 09:07 PM

The bit that does the work is the horiziontal plate, get an open tupperware container and put some vertical baffles in it and shake, water everywhere, remove baffles cut a hole in the lid and shake, it all stays inside.

The best baffles have a lip facing downwards where the holes are pressed through this helps keep the oil down, the entry point being the same diameter.

If it surges under braking just weld a vertical baffle across the front of the sump, lean it down towards the middle to help the oil flow back.