Im currently running a BSPT fitting off the rear of the block to a -3an line, then to a T fitting which goes to my oil pressure gauge and to my stock sensor.

Can I also use -3an line for the VTEC feed? Or is it too small? Should I run -4an off the block and to the head?

The thing is, the 1/8" BSPT off the block is TINY! I mean the hole in the fitting is like a -2an. I get 80+ PSI above 4000 RPMs which is more then enough to activate VTEC.

 

Use the 4an

 

Reason?

 

In my experiences the 3an can be restrictive in oil flow.

 

everyone i know uses 3an either works so dont worry to much.

 

Cool I will note that for future reference, everyone I know uses the 4an and has had problems with it, but maybe that was a personal thing for them