3rd Gen Tacoma 3.5L Twin Turbo Kit Improvements and Fixes

The intent of this thread is to allow for documentation and distribution of problems, fixes, improvements, and advice on improvements to the twin turbo kit that is very slowly making it's way into 3rd Gen Tacomas.

Background: There is currently a twin turbo kit in limited circulation and currently still under development that was provided by a company that will not be named. This kit uses two Garrett K0-1 turbos from the ford ecoboost to significantly improve power to the 3.5L 2GR-FKS. The kit is being sold by a small company with limited staff and support and as such suffers from extended development, correction, and distribution.

There have been a number of documented problems with installation that remain uncorrected as well as methods of improvement that can benefit the kit/installation. Unfortunately the original 600+ page thread devoted to this kit is now locked and due to it's size is very difficult to find the information needed.

The guys installing/already installed this kit want a place we can document installation instructions, corrections, and problems to assist each other with creating a seamless installation for anyone who follows. Improvements for reliability, dependability, and efficiency are greatly appreciated.


This thread is NOT meant to trash talk anyone, discourage sales, or be a forum for whining/complaining. Do everyone a favor and keep that stuff to private threads.

- Please keep nonsense out of this thread to allow for consolidation of information for ease of reference.

- This thread is only for the twin turbo kit meant for the 3rd Gen 3.5L V6.

- Baseless criticism is not helpful. Let's keep this educational and informative. This is a technical thread.

 

Turbo Boost Reference Port Installation

Parts Needed:
Drill or Drill Press
15/64 Drill Bit (or "D" drill bit)
1/16 NPT Tap
1/16 NPT Wastegate Hose Barb Fittings - x2 Link
Thread Sealant

If your kit doesn't come with the turbos pre-tapped for boost reference and you don't want to use the push through barbs that go on the couplers, drilling and tapping the turbo compressor housing where it is originally intended is easy and will give you the most reliable reading at the turbo for wastegate actuation.



The most important thing is to remove the compressor housing first so metal shavings do not get in the compressor wheel. Make sure you mark the compressor housing in a few spots so you can re-clock the housing to where it's intended. See below. Do these one at a time so you don't mix the housings up.

Remove the 8mm bolts holding the wastegate actuator to the compressor. Then remove all of the 8mm bolts on the housing as shown below and remove the housing.


The compressor housing should slide easily off the compressor wheel. Set your housing on a flat surface if using a hand drill or on your drill press. Mark the exact center of the casting flat with the yellow arrow above with a sharpie.

CAREFULLY drill the exact center of this flat slowly with your 15/64 or "D" drill bit. You may have an easier time starting with a much smaller drill bit to drill a pilot hole. Go slow so you only penetrate the housing and not the air plate beyond. The most important part is that you are perfectly straight with your hole.






Grab the 1/16 NPT Tap and start cutting the threads. Ensure the tap starts straight. Getting it started straight is the hardest part. DO NOT THREAD ALL THE WAY THROUGH. NPT threads are tapered. If you thread too far your fitting will bottom out before it ever engages the threads properly for a seal. You should cut threads just slightly longer than the threads on the fitting.

I recommend you cut about 3-4 threads, then test fit the fitting. Then cut one thread at a time until the fitting is hand tight with no less than 1 thread between the base and the housing. This way when you tighten it down it should stop snug just shy of the housing.



Wash all of the metal shavings out with running water. Be thorough. Shake or wipe it dry, then let it dry on a rack for a bit. Blow air through the threads to ensure no water clings in them.

Once dry, apply a small dab of thread sealer on your wastegate fittings' threads and hand thread them finger tight. Take your wrench and tighten it a little more. Do not overtighten. You aren't torqueing this, just making it snug so the sealant and tapered threads can do their job. Overtightening will strip the aluminum or break the fitting. That's an expensive mistake.

Here is the end result. Repeat on the other housing.

 

@MESO @3rd_gen_trd_taco @Bigetaco22 @Jrgymie @KnckleChldrn @mZiggy @Turd Hawg @TWTaco @RedLantern @BlkdOuT @naked farmer

Please add anyone else I'm missing here.

 

Oil Sensor Fitting Correction

Parts Needed:
Pressure Gauge Adapter, 1/8 BSPT male and female, 1/8 NPT female.
- The NPT fitting needs to be on the side.

Amazon has a bunch of these, but most have reviews where someone received them with the threads done in the wrong spots. I ordered from a reputable supplier. Link

The fitting that is provided in the kit that enables the use of both the factory oil sensor and the needed oil lines for the turbos is incorrectly threaded. Please verify before replacement. Verification can be done easily using parts from the kit. Take the black NPT tee fitting for the oil lines and GENTLY try to thread it into each port on the fitting. The Tee is NPT threaded. If it threads in nicely a number of threads before getting snug, then it's NPT. If it instantly binds, it's BSPT.

Vice versa, if you try and thread BSPT into an NPT it will rattle very freely and never actually seal, even with a ton of sealant.

These threads are not interchangeable. If you try to interchange them, your fitting will leak, or you will destroy your threads.



This fitting is intended to be installed so that the oil pressure sensor (BSPT) threads onto the back port, while the turbo oil line tee (NPT) threads into the side port. This is important for clearance of the fan blades. Ironically you can see below that there is oil leaking from that fitting.



****EDIT****

Here is an alternate method for installation. One of the guys used the back port on the original fitting (left fitting above) for the oil tee. If you don't want to replace the entire fitting you can get two 90 degree AN fittings and use them to route the lines correctly as shown.

No matter what you do, ensure the correct threads are being utilized by test fitting before installation to identify the type of threads as discussed above. This will prevent leaks.

 

Fuel Pump Ground Wire Replacement

Parts Needed:
Sumitomo TS/SL Female Terminal 05. - 1.25 mm - 2x (Pump and FPC) Link - order extras just in case
Sumitomo HX / DL / SL Sealed Series Female terminal - 1x (Tank) Link - order extras just in case
Wire Crimper, Molex/Mini-PV connector

$23 iCrimp SN-025 Dupont Crimper, O Crimp Tool, D-sub, Dupont Connector Wire Crimp Tool AWG 28-18(0.1-1mm²) for Harwin, Amphenol MINI-PV Connectors Molex KK 396 Micro Timer Connectors

Link - or something equivalent
14 gauge multi strand automotive ground wire - 10 ft
Tools: Wire cutters, Wire Strippers, Electrical Tape, Razor blade, Dental Pick

Toyota used a very small gauge wire to ground the low pressure fuel pump inside the fuel tank and from the tank to the Fuel Pressure Controller (FPC). Under high loads, mainly those demanded from a larger upgraded low pressure fuel pump like the DW300 used in the high boost Powermax applications, will cause the wire to burn up. In order to run an upgraded fuel pump you need to replace the entire ground wire with 14 gauge wire.

I'm told this isn't necessary for the base turbos without a fuel pump upgrade, but I've not been able to test voltage and current loads by the factory pump under heavy boost to verify this. With the pump upgrade on the powermax turbos, it's highly recommended you do this, especially running more than 7psi boost.

Identify the wire: Driver side frame rail, between the fuel tank and the FPC. You will need to have the fuel tank dropped for this.







Fuel Pump Connector:


FPC Connector:



Carefully separate the harness from the frame by cutting the electrical tape holding the loom to the white clips along the frame.

Very carefully cut along the harness with a razor blade to open it. DO NOT NICK ANY WIRES. Either go along the loom or find the seam and go shallow at an angle (versus perpendicular) .

It's hard to cut the entire length because of two sections that sit on top of the cross frame. Taping them back up would be difficult so I left them and just used a coat hanger taped to my wire to feed the wire through those sections.

The wire in question is the White w/black stripe (NOT Black w/white stripe). It's obvious because it's the only thin wire. You cannot actually remove this wire completely because it's in it's own sheath inside the loom. You'll need to just run a new wire inside the loom.

Run the wire before crimping anything to it. Just stuff it into the loom where able and feed it with a coat hangar in those two other spots. They are tight so keep your hangar/wire taping thin.

Once the wire is fed, open up the connectors. The Fuel Pump connector is black and has three black tabs holding the back in place. Carefully pry those tabs to open the back. Here is the wire:



Don't just pull the wire. You need to release it from the inside. On the front side of the connector is a white retaining piece. Using a dental pick, pry between the rubber seal and the white piece. Work your way around carefully and just pry it up. It'll stop near the end. It'll take a little extra pressure to overcome the stop, but it will come off. Keep going until the entire piece comes off.



With the retainer off, look inside the front of the connector. You are looking for a tiny black tab inside that physically blocks the wire from backing out. Put your dental pick between the black tab and the metal connector pin and CAREFULLY pry out. Don't pull on the wire until you pry the tab out. Pulling the wire will actually lock the tab in place. Pry, then pull. If it doesn't slide right out, you didn't do it right. It won't take a lot of force. You are removing the thin wire only.




Once the wire is out you can see the metal pin and the connector seal. You need to retain this seal unless you ordered new ones. Just carefully pry the two metal pieces holding it on and slide it back along the wire. Cut the pin off and slide the seal off the wire.


Cut your long wire to about the end of the entire connector. Strip off about half an inch of insulation. Slide your little seal onto the wire. It needs to overlap the insulation about halfway. The point is to not have any exposed copper wire behind the seal. Make sure the copper wire is exposed enough to extend into the connector just past the crimp as show above and below. Put into crimping tool and crimp. It should look like this (albeit this one crimped a little tight on the seal). This connector will use the smaller of the pins you ordered. The bigger one won't fit in the connector.




Slide the new pin into the connector until you feel the tab snap into place. My crimper tends to bend the connector pin a little so you may need some tiny pliers to bend it straight. Give it a little tug to make sure it's seated. Orient the white retainer back into place and slide it down until it snaps into place against the red seal. It only goes on one way. Then push the back piece on until it snaps into place. All done.


Now on to the FPC Connector. This one will be fairly similar. There is no back piece to remove on this one. You'll only need to look at the front of the connector. The white retainer needs to be removed. Using a dental pick, carefully pry up at the two marked holes in the connector, alternating between the holes until it comes out.


Once you remove the retainer, you'll be able to see the plastic tabs inside, just like the other connector. Same thing, carefully pry, then pull the wire out.


Just like the other connector, remove the seal, cut off the pin, attach seal and new connector to new wire. Then put the wire back in the same way and re-insert the white retainer. The end result should look like this:


I left the old ground so you could see the difference. You can cut the old ground back to the wire protector since it's no longer needed. The seal on mine is sticking out a bit because of the wrong crimp. Ideally you want it to be flush with the rest.


The new fuel pump wire can be pinned using the same method. The connector in question has the pin retainer on the side, not the front or back like the others. You'll see the cutout. Carefully pry it out completely (don't lose it when it flies off). Then underneath you'll see a thin white plastic tab that can be lifted a little with a pick to release the wire.

Just carefully de-pin the old ground inside the fuel pump hangar and crimp one of the larger of the two pins (the same as the FPC) onto the end of the black wire from the new pump (don't trim it, it's just long enough). Re-assemble and plug it back in. It's pretty easy but I forgot to take pictures. The end result should look like this:




The other three wires (positive yellow, blue, and pink) all get combined and connected to the new red wire. Use fuel resistant marine grade heat shrink with glue inside. Crimp and solder said connections before heat shrinking to ensure reliability.

 

Thanks for setting this up @JamesT

 

I attempted the install during thanksgiving week and saw that this install will take longer than expected and reverted back to stock since truck is my daily. I got to the point of dropping in the passenger side for mines but my WG actuator was hitting the fender well preventing it to clear properly. AC Lines were pulled/pushed out of the way to clear. Has anyone else had this happen to them? Would like to know your solution as im considering to attempt it again.

 

You most likely just need to re-clock the turbo a little. It can be accomplished pretty easily. There are two ways you can accomplish this. In between the Compressor Housing and the Exhaust Turbine Housing is the cooling hub, where your coolant and oil lines all attach; that will clock both the hub and the Compressor. Alternatively you can clock just the Compressor housing.

Before you do that though, there are two bolts holding the Wastegate Actuator to the mount, and 2-3 bolts holding the mount to the compressor. Loosen one or the other, or both and see if you can move the actuator enough to clear. It will move a little, and may be enough.

If that doesn't work move on to clocking:

I recommend you start with the cooling hub first since it's easier. The picture below shows the v-band clamp that holds the Turbine to the hub. Just loosen it and rotate until the Wastegate Actuator is no longer making contact. It should only need a minute amount of movement to do this. Too much and you are going to throw everything out of wack. Things you want to watch for as you adjust it:
- Drain remains oriented downwards
- Wastegate Actuator Arm does not bind



If things get too out of alignment, you can loosen the bolts holding the Compressor on (on the compressor backside) just a tiny bit and rotate only the compressor. Keep them decently snug (hand tight) so the housing only spins with a little effort, but doesn't free spin. This will be painful to do on the truck so do this only if the first method doesn't work or you need to adjust more than the hub will allow.

 

Thank you for this thread I will be undertaking these upgrades when I can soon.

I have a question beside the obvious things I’d already take, if I was taking the turbo taco into the deep bush in say Utah what spares would be useful in a pinch?

 

You should post this in the technical chat. Way less smut there. Or at company who should not be named website.

 

In your first few posts. ~2-6, a lot of images are like this. Otherwise, carry on.

 

How deep under water are you planning on going?

 

I can see them all

 

Interesting...maybe an iPhone to android or laptop thing? Some show on my android, but not all.

 

I'm on Android.

 

Same here. I got the question mark box on my desktop and my Iphone

 

well I’m not sure depends on the snowmelt really, three hopefully small crossings on the route. Doing escalate and Canyonlands maze so fairly remote.

I’m thinking a few spare hose clamps at least…

 

With the other TT thread being closed for now, how's everyones install going so far?

 

How's yours going too?

 

Still stalled for now. I realized it’s Not going to be a weekend thing. Waiting to get another vehicle so I can go at it again.