12 valve stuff and what it does

Detailed information for all Turbo related questions!

Oil leaks

My turbo leaks has to be one of the most common questions we get.  There are many factors that can cause this. A few are as follows:

– Oil drain size, for the love of everything thats good please consider anything but a -10 oil drain. Internally they are half the size of the OEM drain passage of an S400. Way too small to ever be recommend by us, regardless of if its worked in the past for you.

– Crancase pressure, a healthy engine vrs a tired one creates different case pressures. Case pressure is turbo case pressure, this pressure can cause restrictions in the drain and push oil past the metal sealing rings inside the turbo.

-Aftermarket tappet covers or valve covers, must be vented atleast as well as factory or case pressure will be higher and thus turbo case pressure.

-Aftermarket catch cans, are for oil containment on the track. If improperly installed these will also increase case pressure due to poor case venting.

-Higher oil pressure, common rails and L5P’s run higher pressure typically than the older engines. This plays into oil volume to the turbocharger itself. we recommend -4 feed lines in all applications that are not Performance oriented if applicable.

-S300’s by design have a smaller internal bearing housing cavity and because of this can be tricky to get to drain fast enough. 

We recommend OEM oil drains on any frame turbos. On any S300 or s400 all turbochargers should be ran with a minimum of a -12 AN drain. ¾ and 7/8 hose with barb fittings is recommended over -12 line. the OEM steel HX35 drain is the largest ID drain there is for a pickup truck. consider modifying this. Our turbos flow much more oil through the bearings than OEM units. If you do not properly drain a performance turbo they very easily can leak. We are not responsible for leaking turbos when the customer runs a -10 drain line.

Once a turbo starts to leak they typically will continue to leak even if the drain size was the original cause. To resolve this, the charger will need disassembled and cleaned.


Powdercoating is an option via a phone call purchase only. This adds a few days to the order shipping. We prefer using illusion colors but can discuss your build.

Turbo seals

These seals are not o-rings. They are metal rings like piston rings. They are designed to be wipers not a seal against a level of oil. Almost always when you think you (Blew your oil seals) you have a poor oil drain causing oil to back up in the cavity of the bearing housing and oil is seeping past these rings. Nothing is actualy broken with the turbo in this situation.

What’s the best turbo?

It’s so very important to spec the right turbocharger for each of your builds. I get asked all the time what is the best, what will spool the fastest, what will make the most power. There is no general best. I need to know what you plan on doing with the vehicle. What application this will be running in, what kind of HP you want to make, all your supporting modifications, what altitude you are at, do you tow, play, race, daily? All of these questions need answered before we decide on the best turbo for your vehicle.

Why don’t you rate turbos for HP levels like other companies?

I am very conservative when discussing HP potentials. I not only want my turbos happy but I want my customers happy with what was built for them. The internet is absolutely polluted with unrealistic HP claims from individual to well-known companies. Many times it is marketing wrapped up in a feel good story for the customer. Other times I admit, crazy numbers are true. I try very hard to build you what you need not what you may have been told works best.

Oil Feed line sizes

Feed lines tend to be overlooked on installs. we have found that OEM, -4 and -6 typically work very well. if you experience a leaking turbo and are running a -6 feed line, consider stepping down to a -4. a -6 ID is much larger than what the turbo can ever use and sometimes this can solve a leaking setup.

also to note, if you have been killing turbos or have seen oil starvation issues it is very wise to replace the feed line just as a precaution. feed lines can delaminate like the rubber brake lines on your vehicles and cause a no flow situation. 

Boost Leaks

Boost leaks are an extremely common issue all turbocharges vehicles encounter. We see it much more in the diesel world as we are cramming tons more air through these pipes and past these gaskets.  Boost leaks can be detrimental to a turbochargers life. Any leak is causing the compressor to do less worth and thus making it easier for the turbine to spin faster. The driver is experiencing less power and gets deepr into the throttle. This causes more shaft speed, more heat and eventually Bang!

If you experience low power or excessive smoke at anytime with your car or truck it is always advised to do a simple leak test. it could be nothing or it could be a split cooler that gets repaired and saves you a melted engine and blown up turbo.


Wastegates tend to be criminally misunderstood. A wastegate is a tool that is used to regulate shaft speed. We can build a more responsive turbo and add a gate to help bleed energy off the shaft. Shaft speed kills turbos. No way to get around that. By adding a gate we can tune things in better to try and keep spicy setups alive. 

Also, many folks believe that wastegate settings are max boost settings. When in fact they have very little to do with max boost. A stock HE351CW is set from the factory around 20psi initial opening pressure. If that were the case no one would make moret han that right? Gates open and close like a door in your house. The harder you push on them the farther they open. All to help regulate the speed of the shaft.