Yes. I currently have the .42s in and have the next size down if needed. When I flowed the turbos I was at 12oz per 30 sec. I still get a bit of smoke when idling for longer periods of time and when warming up. Hellion said they wouldn't hesitate to put the next size lower in but I haven't gotten around to it. Easy to install but to be honest hellion or precision wasn't worried about a little bit of smoke and that it was better to have a little to much oil than not enough. I would probably change up the return lines a bit before doing anything else.