OVTune 3.5L Tacoma Supercharger and Twin Turbo Systems

EDIT 2: also the drain plug is pretty small. Will it support the volume of return oil from two turbos?

 

This type of setup has been done before on turbo kits. It works fine as long as the turbocharger sits significantly higher than the oil level.
The turbos sit at the valve cover level, so the oil would have to get backed up all the way to the top of the engine in order for it to not properly drain. We will test it in various off road conditions though to be sure.


Turbos don't flow as much oil through them as I think you guys think they do. They have a 1mm pin hole feed line,

 

hope its ready for tax return season lol

 

I think something might be wrong with your hairdryer.

 

Must be an ECO boost friendly hairdryer too as it runs off the water.

 

Yes, there are 2 different compressor housing options.
One with VTA and one with recirc, both built into the housings.

 

First potential energy alone will over come the volume of oil in the pan. But not just that but the oil pressure at the turbo is far higher then atmospheric pressure in the pan. As far as drain plug size goes you actually restrict oil flow in a turbo usually with a 3-6mm hole. You need to maintain oil pressure in the chra inorder for the the thrust bearings to work.

 

It sounds great in theory, don't get me wrong. However, there area lot of variables here and I think it will be a little different when applied, especially in an off-road environment. Are you saying you restrict the DRAIN of the turbo to 3-6mm?? I am aware of restrictors on the feed, but it sounds like you are saying the drain as well... Having built race cars and drift cars that are constantly sloshing/slinging oil I have always gone with the largest and least restrictive turbo drain line as possible and plumbed it high on the pan or even in the side of the block. I know technology has changed so I guess we'll see where this goes. I am eager to see if it gets tested with a clear drain tube, as that will really show what the oil in the drain is doing.

 

the turbos utilize a 1mm oil feed restrictor, and a 5/8 drain tube.

 

Tacomaworld:
"The new ford ranger sucks because it has turbos and turbos are unreliable!"

OV Tune:
"Twin turbo system for the Tacoma is on the horizon"

Tacomaworld:

 

google bernoullis equation if you want to understand the theory behind the design

 

So true.....

 

That's what I thought. They are 5/8s for a reason, no? So running 2 separate 5/8s drain sizes to a smaller hole that is additionally on the bottom of the pan under the oil level just seems sketchy to me. I know there isn't a whole awful lot of volume coming through one turbo, but they are designed to flow one through a 5/8s drain, not two through smaller.

Either way, I am trusting you guys as I plan to purchase this kit when its out, but personally (and I know my opinion means nothing cause I am not building it) I would tap above the oil line in the pan.

 

Great summary, but I think you missed the critical element as to why the ranger sucks. I embolden it in blue for you

 

@OVTune as far as heat protection goes, have you decided if you’ll be using turbo blankets, heat shielding or possibly both?

 

Updated it. Still valid.

 

Yes draining in the block is best design practice. In a race car you drain as fast as possible as you are running the turbo a peak rpms and it's hot more oil more cooling. But for longevity in the oem market it can be beneficial to control the oil return. This can help with warm ups and cool downs. In the end the total flow is control by the inlet restriction

But to get back to the theory the oil pan can see slightly higher then atmospheric pressure due to blow by combustion. Worst case scenario would be when the oil pan is completely full which would be at start up. But 2 inches of oil isn't going to have much higher pressures then atmospheric pressure and the potential energy of the turbo alone will always over come this. Remember everything wants to be equal so high goes to low until it's the same

Another thing to point out is people used to run sealed CHRA's with just a bath of oil and they would last 30k miles. So if for some crazy reason it were to back up it would be short lived and would probably have little effect on the overall life of the turbo especially with a water cooled housing. Most of the turbo life is reduced from coked up oil that leads to improper lubrication of the bearings causing them to fail over time. The biggest effect backed up oil would have would be reduced spool up due to higher drag coefficients. Also if the Garrett turbo has the ceramic ball bearings then you could run that turbo dry and it would last beyond 30k miles.

 

Interesting points, thank you.

I would like to say that my main fear would be what you stated. While oil starvation isn't likely here, the oil coked up in the bearings from the level being too high after engine shut down could be the killer. As if somehow the level backs up to the turbo(s) and just sits inside the bearings while unable to drain. It may not be an issue while running on flat ground and having that constant inlet and drain pressure to the pan, but say you park on a hill and the turbo cant fully drain? Or perhaps it backs on coming down or up a steep incline? I would think there is potential for that oil to simply sit there and coke up the bearings.

I guess I am old fashioned, but I like my drain line to only have oil in it while the system is flowing, and to have drained completely into the pan when off.

 

If I were going to put this in an offroader/crawler I would vouch for the ceramic ball bearings. You can beat the living crap out of them and they will hold up a long time even with coking. Another option would be after a hard offroad session remove the oil inlet line and spray the chra internals with seafoam. This does wonders for removing that sticky coked oil. I've done that a few times on my big turbo TDI. Drains right out and the wheel spins freely again.