On a bug the deep sump is recommended because the tuna can mounting isn't as strong and the location is prone to damage on a low car (no prob on a 914). The deep sump mounting is sturdy and the sump is strong. I bonked mine and dug up a little asphalt backing out of my driveway with only a few scratches to show for it. The driveway has a deep gutter... Now I go in/out at an angle and all has been fine. Speed bumps are another story as the sump is behind the wheels (I'll carry some 2x6's just in case)...
Tuna can (picture from
www.pelicanparts.com)
Deep sump (picture from
www.tunacan.net):
Also see
Type 4 Oil System from Tuna.
I'm using the Scat unit from
www.aircooled.net. Jake Raby recommends modifying the Type 1 filter that comes with the deep sump for better flow. Shown modified here (picture by systhesisdv):
The folded lip is cut off where the pickup tube extension passes to reduce inlet restriction. See
914.com thread for more info.
I have a RAT T4 2270 (no windage tray). Before installing the deep sump, I could get the oil light on with hard cornering or hard braking. Now it's very robust -- no sags in oil pressure at all when cornering or braking hard. I tried adding a half quart of oil before adding the deep sump, but that had little effect. The deep sump is a good $100 insurance policy, but hangs low. My car is lowered about 3" in the rear and the sump is about 2.75" off the ground at the rear. When I jump my 190 lbs on the bumper, the clearance goes down to 1.5". I think I'm hitting the bump stops, but the stiffer (23.5 mm) torsion bars helps reduce suspension travel. Attached pictures show install -- no leaks, easy install.
Another modification is to add an
adjustable oil pressure switch set to 25 psi. It's tee'd off the oil pressure sender. This way, I'll get an earlier warning in case something goes wrong.