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DIY - TB45E turbo install

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I've noticed elsewhere that these TB45E turbo builds usually generate a fair bit of interest so I thought I'd add mine and explain with pics how I went about it.

I've had this vehicle for 7 years now and I've gone through the usual stages of extractors + 2.5" exhaust system and finally added an Xede piggyback to make some changes to fuel & timing.
Each of these changes adds a little more performance but, as I'm hoping to hook up a fairly heavy caravan one day for the traditional lap, I really thought I needed a bit more power in reserve to cover those overtaking situations that many talk about.

I had thought about selling it and getting a 4.8 but the old 4.5s aren't worth a lot these days even if mine is a Ti with only 132,000 kms on it. I've done a fair bit of work on mine and just knew I wouldn't find a reasonably priced 4.8 in the same nick.
Then there's the fact that I have a heap of spares for the 4.5 (even a spare auto trans), I have the manuals & PDFs, etc and they are a far easier engine to work on than the 4.8 e.g. tappet adjustment is a $300 dealer job.


So, what about power.. the standard 4.8 puts out ~ 130 - 135 rwkW. Most turboed 4.5s can be made to reliably produce ~150 kW under 7 psi. I'm planning to run with the standard internals (don't see any point in opening a 130k kms engine) and limit the boost to 0.3 bar (~4.5 psi). That should give me what I need and still be reasonably kind to the auto trans. I have already fitted a TransGo shift kit to the auto and done the line pressure solenoid mod with a 2k ohm resistor as well as an additional big Davies Craig trans fluid cooler. I have a temp gauge on the trans and run Castrol TransmaxZ in it. My research tells me it should hold up if I don't drive it like an idiot.. at 68 not much risk of that..


Cost.. I did a bit of research and decided that I could keep this project under $4k if I do as much as possible myself. I was a mechanic in a much earlier life (70s - early 80s) and have a pretty well equipped shed. I have a welder and plasma cutter, a press, etc so just about all I need for light fabrication.
There was no way I could have swapped into a 4.8 in the same condition for that kind of money..

This is the vehicle I'm starting with..






These are my costs so far..




One thing I've done throughout this project is always keep the vehicle drivable. Even making up the IC frame, I could always get the airbox and intake pipes, etc back on within a half hour if I needed to use it.

You can't use the TB45E airbox so why not use a different Patrol airbox that drops straight into existing holes and lines up with the original hole in the inner guard where the snorkel enters.
To do that, you need to move the charcoal canister. If you throw it away, you won't get complianced.
I moved mine down behind the bumper. I welded up a simple bracket from some scrap flat bar. Obviously, you'll need longer vacuum hoses.






The clean air intake for the canister must be removed from where it goes into the inner guard. I routed it up behind the left headlight and fitted a small air filter to it.



An important point here is that you'll need to fit check valves into the 2 vacuum hoses to stop pressurising the canister under boost.


Here's the TD42 airbox fitted in place of the charcoal canister. The 3" silicone elbow will point down towards the turbo compressor once it gets fitted.




The mod for the cobra head is easy. There are threads elsewhere where people have done some better mods with flanges, etc but I kept mine simple and just cut the original outlet off with a Dremel and inserted a short length of 3" exhaust pipe with Sikaflex

and 4 screws.




I cut the flat flange off the intake and passed a 3.5" short silicone hose through the hole to join the airbox intake to the snorkel. You need to pop out the left indicator to tighten the hose clamp inside the guard.








More coming...



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Engine management:

I've had an Xede piggyback on my N/A setup for a while now. I was lucky enough to pick it up from US Ebay for a little over $100 incl. Postage.

Here are a couple of Autospeed articles about the Xede and some other choices.



What I liked about it is that the Xmap tuning software is free from Chiptorque - you're not restricted to only authorised sellers/tuners as with Unichip, for example.

The timing profile file for the 4.5 is also free as is the wiring diagram from the Chiptorque website.

Although I didn't buy it from them new, I got excellent replies from emails to Chiptorque and they even sent me a tuning map they had done on their dyno with a 4.5 with exactly the same exhaust mods as mine.

I even got some free advice from their head tuner on using a MAP sensor as the load parameter for the fuel and timing maps.

For the low boost I'll be running, the Xede should handle it. It can pull up to 10 degrees of timing and can alter the MAF signal sufficiently for my needs. There was a recent thread elsewhere where a supercharged 4.8 put out 185 kW @ 5 psi boost using an Xede piggyback.

Another advantage of the piggyback is that you retain all the principal functions of the factory ECU.

To be able to detect when your under boost you must have a MAP sensor. Some engine management systems have them included inside the case.

For the boost I'll be running, a 2 bar MAP sensor is all I need so I bought a GM type from Ebay and mounted it here:


I've taken the manifold pressure for the MAP sensor from the cruise control vacuum hose then a T from that to inside for the boost gauge.


The MAP sensor needs a 5v feed so I've taken that off my Innovate SSI-4 data logger. I also bought a cheap Ebay 12v to 5v converter just in case.

The MAP is wired to both my data logger and the Xede at the moment but I'm still using MAF & TPS for the load signal with my N/A setup.


When the inlet manifold is under boost, the fuel pressure will need to rise to help the injectors open against the boost pressure.

I fitted a boost referenced fuel regulator that will increase the fuel pressure at a 1:1 ratio.


I'll try it first with the factory 270cc injectors but I did buy a set of 370cc RB25DET injectors from Gumtree for $30 that I can swap in if the originals max out. They shouldn't at that boost level.

I have a Bosch in line fuel pump I can also fit if required otherwise I'll get a Walbro to replace the original pump.

More coming...

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Oil return from turbo:

This is pretty easy to do. I didn't remove the sump, just used well-greased bits and taps.

Has a 1/2" NPT bung in it in the meantime. I'll be fitting braided teflon hose with -10AN fittings.


More coming...

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This has been the most challenging and rewarding phase of the excercise so far.

My research convinced me that there was nothing more important than keeping intake air temps down so that meant fitting the biggest IC I could. It had to be top mount because of the winch and auto trans coolers not allowing for front mount fitting.

This in turn meant I had to use a low mount manifold to leave enough room on top.

As this is a budget install, no point in throwing big money at it. Ebay is my friend so I got this:


I knew it was going to be close to the bonnet and I didn't want it to shake with the engine. I also wanted a fan underneath it so I decided the best way was to make a cradle that fixed it to the bodywork.

The cradle would also serve to better mount the fan rather than bolt the fan directly to/through the IC.

Here are some pics of my first attempts using too many silicone elbows which would have meant too many hose clamps and the whole thing a bit too thick where it fits to the throttle body.




So I decided it would be more practical (and look better) if I fabricated as much of the intake piping as possible from exhaust pipe. This would allow me to mount the BOV a bit closer to where it crosses over to the pre-turbo air intake.

I had bought a whole bunch of different sizes and bends of 2.5", 2.75" & 3" mandrel bent 1.6mm pipes from Ebay.

I did the fine grinding to get angle right with an old belt sander I haven't used in years.



Added the air feed pipe for the IACV and welded an 8mm nut on for the temp sensor for the fan switch.


Added the 25mm pipe for the BOV.


This is where it's at at the moment



This the fan I chose. It's a Davies Craig 12"


Here's the fan fitted into the IC cradle.


More to come...

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Intercooler continued..

In order to fit that size IC over the throttle body, you have to move the IACV because the connector plug sits too high.

My thanks once again to JoseM from Panama for this idea. It was his TB45E turbo build pics that showed me that a 76mm thick IC could be fitted over the throttle body.

I made this adapter from some 3mm plate and a short length of 25mm square tube. This allowed me to have the IACV down behind the inlet manifold.

I brazed up some copper pipe & elbows to be able to use the original air feed pipe in the meantime. Also, the wires need to be lengthened.

It's actually light grey but the iPad camera turned it blue..




Here's a pic of the fan mounting bolts. 6mm welded to the frame with nuts and washers fitted first.


This is the clearance under the fan. You'll need to use elbows on the PCV outlets to maintain the clearance.


Small detail on the IC.. I added 20 x 25 x 1.6mm aluminium angle front and rear with pop rivets to have a flat surface for the sealing foam.


Bonnet scoop next..

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Bonnet scoop..

I would have preferred not to do this but with a top mount air-to-air IC you don't have much choice.

This is the Ebay 'Navara style' fibreglass jobbie for $115. Not the real cheapie plastic one nor the higher end $300 - $400 article.

It covers the IC pretty well.


I painted it with rattle cans (we're talking budget install here, remember..)



I took the bonnet off to cut it and fit it. It's very slightly off-colour depending on the angle and sunlight but in real life you don't really notice it.. and it is a 13 year old vehicle after all..



More to come...

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Some small details..

I had a small issue with the inlet pipe touching the cruise control cable so I decided to drop the cable a little but the front bolt of the bracket was under the cable.


I welded a small piece of flat bar to the original bracket so I could use the mounting hole further forward. This allowed me to file the fork down and gained almost 10mm.



Another small issue was the pipe leading to the throttle body hitting the injector connectors. Simple fix - turn 2 & 3 around 180 degrees.

The vacuum hose from the canister was also across the path of the pipe so rather than force it down under where it would rub against the pipe, I simply added a 1/8 BSPT M/F elbow - $5 from Masters.


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Catch can..

Time will tell if this is really necessary on a reasonably low mileage petrol engine but I had to modify one the original PCV hoses anyway so why not run it through a device that could condense any oil vapour.

On top of that, it adds a bright shiny item under the bonnet :)

PCV mod is pretty easy to do on the 4.5. You leave the original rear hose to the PCV valve in place - although I did shorten the elbow for more clearance with the fan. The PCV valve will act as a check valve under boost.

The front hose on the rocker cover is routed to the catch can and another hose from the catch can to the intake pipe between MAF and turbo compressor.

Connected in this manner, the PCV valve works normally under vacuum while the intake air for the engine is drawn through the catch can from the intake pipe between MAF and turbo compressor where it has already been measured by the MAF.

Under boost, the PCV valve will close and any pressure building in the crankcase can exit via the air intake on the rocker cover where it will pass through the catch can and into the pre-turbo intake again.

As the meerkat would say, simples!

This is the $38 Ebay knock off I bought. It's cheap because it has nothing in it which also means it won't catch much because the vapour will go in and straight back out via the 2nd hole.

It does have a sight tube on the side and an oil drain plug.


Very easy to make this work a bit better. We need a baffle to force the vapour to take a longer route. I had some scrap stainless sheet offcuts from my DIY heatshield so I made this:


We also need some medium to condense any oil vapour. Don't listen to those who say use steel wool - it crumbles into fine steel dust that is easily airborne.

I had some Bunnings aluminium flashing left over so I cut a few pigtails with tin snips. These are big enough so they can't get sucked into the system and have enough surface area to condense the vapour - that's my theory anyway..




Almost forgot, this is where I fitted it..


Edited by JFF45
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As mentioned, I chose the low mount to ensure there'd be enough room for the larger IC. I'm thinking it should also result in less engine bay temps down there but I decided to make a heatshield for it anyway. Radiant heat could be significant when it needs to pull hard.

A stainless steel 'mini sheet' from Bunnings is just the right length. Cost $48.

It cuts easily with a hand nibbler and good tinsnips. I didn't want to weld it with the MIG so I just used a couple of 5mm stainless pop rivets on the corners. They're pretty strong - I had to put lengths of pipe on my pop rivet pliers to be able to snap the stalks.

I first welded some additional tabs onto the manifold for the heatshield. I had the manifold made in Tassie. $400 delivered. I doubt I could make it for that money.. and I could never weld that well anyway!


Heatshield pics and how it fits on the manifold:




I had some offcuts so I made up this piece that fits between the compressor housing and the manifold.

Not sure it will really do anything so no comments, please, on that one :)

You can see where it fits in the above manifold pic.


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Here are some different pics of the turbo itself showing how I'm doing the oil feed line and how it connects behind the turbo.

The oil feed can be taken from the block just under the 6th exhaust outlet. It's a 1/8 BSPT thread and the adapter for -4AN connector is easy to find.

I bought all my fittings and braided hoses from Ebay. Good quality and way less than the Aeroflow/Speedflow etc prices here.

Also using a Kinugawa wastgate actuator. They have adjustable length, replaceable membrane and a choice of different springs to set base boost level.

I made the actuator support bracket with a shock absorber washer and some flat bar welded to part of the original support.

As mentioned, I'm starting with 0.3 bar. If I want to go slightly higher later, I'll probably do it with a boost controller.

The water inlet feed can also be taken from the block. There's a 1/4 BSPT plug in the block for emptying coolant. I'm planning to 'T' into the heater return for the return flow.





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Some miscellaneous stuff..

A really good accessory to have is a wideband gauge that indicates your air/fuel ratios under different conditions. With a turbocharger added, this becomes indispensable, IMO.

I chose the Innovate MTX-L. It also has a narrowband signal output that I'm using connected to the ECU in place of the factory sensor signal for closed loop operation.

I mounted it here with my trans temp gauge:


I welded a bung into the exhaust ~400mm before the cat - where the extractors form a single pipe. I'll use the same location for the turbo.


One of my biggest concerns is detonation. There's no doubt that this has been the cause of most TB45E turbo issues with connecting rods.

Sure, you can strip your engine and beef it all up with stronger components. It's all a question of how far you want to go with it power wise and how much money you want to throw at it.

This is a thread about a low boost budget install so it's going to be using stock internals and we're going to do our best to keep that engine safe by other means..

Enter the visual knock detection device. These are sold on Ebay by a guy in Lithuania who makes them himself. They have good write-ups and my friend Jose in Panama confirms they work well with the TB45E factory knock sensor.

They will show a green LED when all's good and progressive orange LEDs when knock begins then a bigger really bright red LED when knock occurs.

I plan to use it as a visual aid i.e. have it more or less in line of sight so I can lift off when required.

I paid $20 extra to get the 5v output signal with it so if it indicates regular knocking, I'll log it to see why and when it's happening and adjust the Xede accordingly.

This is the size compared to my phone:


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If you need to go to bigger injectors, most of the Nissan side feed models will fit i.e. they go into the TB45E fule rail and the O-rings, although thicker, will seal in the TB45E cups.

One difference I've noticed is that the bigger injectors have a 3mm plastic border (as shown in the pic here) that doesn't fit inside the TB45E cup so the metal cap can be overtightened if you're not careful.

The solution I used was to fit 5mm nuts in the space - 2nd pic

370cc injector from a RB25DET Skyline on the left. Standard TB45E injector on the right.



I found 6 of these 370cc injectors on Gumtree for $30 including the Skyline fuel rail.

As the local auto elec wanted $35 each to clean them, I set them up in the original fuel rail and ran pressurised kerosene through them. Spray pattern was good on each of them.

I've since removed them so I can first test if the original injectors really need to be replaced with the low boost.

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If you need to go to bigger injectors, most of the Nissan side feed models will fit i.e. they go into the TB45E fuel rail and the O-rings, although thicker, will seal in the TB45E cups.

One difference I've noticed is that the bigger injectors have a 3mm plastic border (as shown in the pic here) that doesn't fit inside the TB45E cup so the metal cap can be overtightened if you're not careful.

The solution I used was to fit 5mm nuts in the space - 2nd pic

370cc injector from a RB25DET Skyline on the left. Standard TB45E injector on the right.



I found 6 of these 370cc injectors on Gumtree for $30 including the Skyline fuel rail.

As the local auto elec wanted $35 each to clean them, I set them up in the original fuel rail and ran pressurised kerosene through them. Spray pattern was good on each of them.

I've since removed them so I can first test if the original injectors really need to be replaced with the low boost.

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As I mentioned at the start of this thread, I'm running an auto trans with this project and I added a Davies Craig cooler for the trans fluid.
This involved relocating one half of the power steering cooler from the right to the left side and I thought it might be of interest to others how cheaply this can be done.

For those using a manual box, this might also be a handy mod if they want to mount a radiator for a W2A IC.

This is the standard layout on a TB45E..


..and this is what we want to achieve:



These are aluminium tubes and I have nothing to weld them.. and they are probably too thin for the average amateur to attempt to weld anyway.

As luck would have it, the tubes are just the right size for these 1/2 brass plumbing elbows with the nylon olives..


You just need to be able to silver solder a short length of copper tube with 2 copper elbows to join this part here:


I decided to retain the original trans cooler and connect it in series with the new Davies Craig. I had to move the original ~25mm forward.


This is the finished mod. I've been running it now for over 6 months and not the slightest sign of an issue.
There's very little pressure there anyway.
From memory, cost of the brass elbows for this mod was <&#36;15..


This is the cooler I used. Bought from Ebay.


The highest temp reading I've seen since is 80C. Before the extra cooler I could get it to ~105C so a turbo installation definitely needs this mod.
Standard temp on the highway with the TC locked is between 60 & 70C which is almost a little too cool.

I'm also planning on removing the cooling pipes that run through the radiator.
There has been more than one report of failure of these pipes resulting in mixing of trans fluid and coolant in both the trans and the engine.


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  • 2 weeks later...

Just thought I'd add some pics of fittings on the turbo. I initially used an adapter for the oil feed with the 1mm restrictor (as shown a bit earlier) but I was never really happy with the number of connectors needed to guide the feed line in.

This is what I mean - there's the adapter/restrictor then a F to F -4AN elbow (couldn't find F to M) then a M to M union to be able to fit the elbow from the feed line.





Then I found this the other day.. a banjo fitting with the 1mm restrictor in the banjo bolt and a -4AN inlet.
This is also a much lower profile and allows a lot better access to one of the T3 flange nuts. With the previous connectors, I had to clock the turbo a couple of degrees more to make sure I could get a socket onto the flange nut.






Here's a pic of how all the fittings should be as seen from the block side. The oil feed is much neater now. The water cooling will be also be banjo fittings with -6AN cones (also from Kinugawa) and the oil drain is -10AN.




I've seen installations where rubber hoses have been used for both the water cooling and the oil drain but the teflon braided hoses and fittings are not a lot more expensive if you source them from Ebay and make them yourself.
They certainly look a lot better..


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