What are people's experience with dry sump kit are they worth the money? What's the chance of an dry sump having bearing failure compare to an wet sump set up?

 

the dry sump pumps I've seen (not sure if the well known subaru kits use the same type), have a the pump drive shaft running directly in a machined surface in the pump housing, i.e. not a "bearing" as such.

The shaft is probably being adequately oiled from capillary action of the oil in the "pumps" (i.e. there is some clearance between the shaft and the housing, which will be filled with oil once the pump starts moving oil), however as the housings themselves are usually an aluminium alloy, i'd expect the shaft to wear the machined surface over time (making it oval), which will give wobble on the shaft eventually.

I would personally expect the external pumps to have to be replaced or rebuilt at regular intervals at "main / only road car" type mileage, but last for a long time on a "sunday only car".

 

They are worth the money if you have a fair investment in the engine, if your running slicks on your car there is a good chance you will suffer oil starvation on track with a baffled sump system, however good it is.


Although in my experience with dry sump systems on Subaru engines, if your at the requirement of a dry sump you would have Arrow or similar billet crank fitted, which does have superior oiling system over the OE Subaru item, this goes a long way in protecting the bearings, especially at high rpm, & I am talking about dry sump systems that do not still use the oe pump to supply pressure to the engine.


If your engine is in anyway suffering detonation etc it will still hammer the bigends regardless of what oiling system is fitted.