Advice on dry sumps, Peugeot XU

[Barking Mat]

That is one serious, ERM, mental project. Your fabrication and engineering skills, alu welding!
I got as far as page 3, I'll save the rest for bedtime.

Thank you mods for moving this.

 

[PhillipM]

I did laugh a little when you said give me 5 minutes

 

[Jim Davey]

Phil knows what he's talking about, I have a rough idea but building a working dry-sump system takes a bit of research and preferably some experience. Engine problems from oil starvation can get really expensive really fast, so if you are in any doubt that what you are doing isn't 100% right, get some professional help.

 

[thinfourth]

Now unless i have the wrong end of the stick the car already has a dry sump but he is suffering an issue under acceleration

It will be a low pressure/gravity feed from the back to the front where the high pressure oil pump is. the high pressure pump will be engine driven and will give the engine oil pressure. this is suffering oil starvation and no pressure.


So he needs to increase the pressure from the tank at the back to the engine at the front.


option 1

Mount the oil tank higher up. No idea if it is doable but it will also move the center of gravity up


Option 2

A low pressure high flow electric pump at the back feeding into the high pressure pump


option 3

Use boost pressure and pressurise the tank to 2 or 3 psi using a bleed from the turbo. This must be regulated down to a very low pressure otherwise you may damage the tank. You will also need to pay attention to the tank vent as part of the function of a dry sump is to let air/gas escape from the oil. So you can't cap it off as it must constantly vent gas/air

 

[bert]

Mine does not sufferer a pressure drop under acceleration in fact it increases with revs, my tank is in the engine bay though so no long runs of oil pipe. Here is a pic as i was plumbing it all in. The tank is in the front of the picture.

WP_20170407_19_12_31_Pro by bertmuppet, on Flickr

If his tank is in the boot then i would say to fix it is to move it into the engine bay and this should solve the issues. It will also reduce the weight as I guess he will be running something like 7-8 litres of oil plus all the pipe.

I run 3.5 litres of oil in mine

 

[bert]

Oh and here is a pic of the pump on the block, one pick up from the sump, one feed from the tank, t for the remote oil filter and one return to tank via the oil cooler

WP_20170406_20_34_23_Pro by bertmuppet, on Flickr

And to keep it on track for a welding forum here is the dry sump pan I made and tig welded up.

WP_20170403_20_31_57_Pro by bertmuppet, on Flickr

WP_20170403_20_31_48_Pro by bertmuppet, on Flickr

WP_20170404_17_39_13_Pro by bertmuppet, on Flickr

 

[Stueeee]

If you have a dry sump system already and the pressure drops on acceleration, I'd be looking at whether the dry sump tank was tall enough/is well baffled enough first. The tank needs to be tall in order that the oil (which is mostly froth) from the scavenge pump(s) has room to settle out, and also so that hard acceleration/cornering/braking doesn't uncover the outlet to the pressure pump, which does sound like what's happening on your friend's car. The baffling needs to be horizontal; the home fabricated tank on my car has swaged holes in the baffle plate which is about halfway down the tank. Neither of these pics are great quality, but they hopefully show what I mean.