i mean there is pretty much no restriction at all through the center of a journal bearing turbo no matter the country of manufacture. the oil is there to remove heat and be present for fluid-dynamic lubrication.

so take a -4 an line, put 25 psi through it and its gonna make a mess

pumped about 6 qts out in 3-4 minutes. valve train started clacking like a ************. hose clamped it and added some juice and seems to run fine haha gotta love this SBE life

 

Fbodys simply don't have the real estate for massive returns that eliminate the need for a restrictor. That's why many fbody guys run restrictors....and they put thousands and thousands of miles on their turbos without failure.

 

FWIW, finally got to the dragstrip this past Saturday, for the "Grand Opening" Test & Tune...made 5 passes, and nobody saw any smoke, so I guess mine's "fixed"...lol.






.....or outta oil.

 

I got a 7/8 OD soft copper drain on mine.

It won’t melt. It won’t move into a belt, pulley, or the exhaust. It stays exactly how you bend it so it won’t move and rub a hole in itself. It also has a full 3/4 ID.

I have used various materials of different sizes. Mostly smaller alternatives in the past without issues. But one night while laying in the garage floor looking up at the turbo, I thought of the copper I had left from a ac install. It solved every single issue I had with turbo drains lol. Overkill maybe, but works great 😂

 

LOL that does sound like overkill, but hey if it works for you then sweet! My front mounts were too low and the drain line always seemed to get in the way of the swaybar/belt. That said, I've never killed a turbo due to an oil restrictor and run smaller drain lines. Just more than 1 way to get it done.

 

funny.....

 

Haha 👍

Looks nice too!.

I put everything in and laid under the car and sweat it in. 15 years of being a HVAC tech and licensed plumber, I’ve never fought a simple solder joint so hard. The pan is such a huge heat sink it took everything map gas had to do it. Next time I’ll get the oxy/ace and braze it in

 

It's not overkill... In fact it's what most manufacturer recommend! All the AN stuff necks down. Even AN12 doesn't meet the manufacturer suggestion in most cases. Borg/Holset/Airwerks etc... all suggests no smaller than 19mm ID. Which is 3/4. If you look at the Garrett manuals they suggest 1" on large frame turbos and 3/4 or larger on most other. The china copies are cloned off these turbos... and should follow the same guide line. Anyone telling you to run a restrictor is telling you to shorten the life of your turbo. Which to be fair, is likely fine to some degree for our applications. The big drains and flow recommendations are to get max service life on the turbos. Most of the large frame stuff is designed to go 300k+ between overhauls. (semi-truck stuff). I'll never see a 1/10th of that mileage on my toys... And the vendors know people just want their new turbos not to smoke.

Personally... I think you should design the kit to have a proper drain and not limit the oil supply. I'm also a big believer in using what works for you! lol. I also use 3/4 copper pipe for my S400 drains. A true 5/8 ID seems fine on the T3 small frame stuff. I use it on my GT35 twins with no restrictor anyway.

 

flexy gas line for like water heaters can be had in 5/8 ID....however they appear to only be available with the ends that go from 5/8 flare to 3/4 npt and all my stuff is 1/2npt

 

[QUOTE=lower_the_dynamite;20252824]I had to put a restricter and on my new build with a high volume/high pressure pump and it was smoking a little after hard hits. As soon as it was installed, its been perfect for over a year.[/
What size oil restrictor did you use?

 

Turbosmart make a pressure regulated restrictor to the tubo it is an in line piece that keeps pressure no higher than 40psi.

 

There are a few stock applications that come with a restricter from the factory.
The tiny CA18 in a Nissan S12 had one, if you didn't it would back foam up the drain, even when I upsized the drain tube with 1" hydraulic line.
I used a carb jet as a restricter and it was road raced for several years that way. YMMV