oil return line bung question

[palauoriginal]

does the oil return line bung size matter?

and does the material its made out of matter?

 

im planning on using a 1/2 NPT steel bung for the return and 1/8 NPT feed with a 300zx t3 turbo.

 

would this work?

[MrFancypants]

The size of the return doesnt really matter, -5 or so more than enough. That feed size is gigantic. Do some searching on "Oil restrictor".

 

 

 

- Greg -

[RB26powered74zcar]

The size of the return doesnt really matter, -5 or so more than enough. That feed size is gigantic. Do some searching on "Oil restrictor".

- Greg -

 

 

I gotta disagree..... I learned from experience, the larger the drain return line, the better. To small and you'll have problems with oil not draining fast enough, and pushing out the front inlet and rear turbine.

 

On your supply line, it depends on what type bearing it uses... duel ball bearing requires a small supply of oil (use of a restrictor), the non BB turbos need more oil for a good oil wedge to survive...

I use -3 supply, -10 return, with restrictors in the cartridge on my Garrett BB turbos.

 

Pressure is another issue....

[MrFancypants]

I guess my post was a little misleading... the size does matter but it doesnt need to be huge. The larger the drain the tougher it will be to route back to the block. I also had a -3 feed line (with restrictor) but with a 3/8" outlet. -10 seems overkill to me -- I never had any problem with oil not draining. From -3 to -5 or -6 is a pretty massive size change, even without a restrictor. IIRC the stock turbo drains on a 300ZXTT are about 3/8" (-6).

 

 

 

- Greg -