Eddie, a tech on our race team and a tech here at the shop did this small write up regarding a 2.7L Boxster Turbo Build. We are very proud of the results and it made for a great car! This car received the $7,490 system(Low pressure/non intercooled).

Without further adieu!

In our attempt to make 2.7L Caymans and Boxsters more fun to drive we are making a specific non-intercooled turbo system for the car.

Car in question is a 2.7L LE Boxster as pictured here...





Eddie, our tech building the car will do a full write up on the installation in order to make this very DIY-able.

First, baseline dynosheet.


Airbox Removal/Modification

The guys in the shop got busy tearing down the Boxster today. It would be a good time to cover modifying the factory airbox for TPC Racing 987 Turbo Kit. This part of the install applys to both Standard and LP (Low Pressure) Kits.

First thing to do is disconnect the battery. We will be removing fuel rails and fuel injectors.

Then, gain access to the engine bay by lowering the convertible top 1/3 of the way (Boxsters), removing the speakers, removing the carpeting (4 - twist caps), and finally the hard engine cover (5 - T35 Torx bolts).

You should see something like this.


In order to remove the factory airbox for modification, the driver side intake manifold has to be removed. While we are in there, it would be a good time to change the fuel injectors and install the oil feed line for the turbocharger. So, let's cover that here.

Throttle Body/Center Log Assembly Removal
We can begin by removing throttle body/center log assembly by loosening the hose clamps around the intake manifolds, disconnecting electrical connections, A/O Separator lines, and vaccum line to the valve under the center log itself.

Picture of the engine bay after the removal


Picture of Throttle Body/Center Log Assembly


Once the throttle body assembly is removed, the vaccum line that went to the valve under the center log needs to be capped in the car. Also, the solenoid for Sport Exhaust needs to be disconnected, since the whole exhaust system will be removed. This solenoid is mounted on the engine hook from factory. The engine hook is to the right of the throttle body and needs to be removed for the turbo kit install. The solenoid is pictured in the engine bay shot, towards the bottom right, on top of the bell housing. The outlet of the solenoid (the line that leads to the back of the car) needs to be capped after disconnecting the line.

The picture of the Sport Exhaust Solenoid


Fuel Rail Removal
The fuel rail is held onto the intake manifold with 4 - E10 TORX bolts, 2 of which sits between the intake manifold runners. 8mm socket will work on these.
Once the rail is loose, carefully pull up on the rail to remove the injectors from the manifold. Leave the fuel line on the rail.
Once the whole fuel rail assembly is pulled from the intake manifold, start replacing the injectors by removing the clips. Then, pulling the injectors out of the rail. When installing new injectors, apply some rust penetrant (Nut Cracker) on the injector O-rings so that they do not get cut during the install.

Fuel Rail after removing the injectors


Intake Manifold (Driver Side) Removal
After the fuel rail has been lifted out of way, you can start removing the remaining 2 - E10 TORX bolts holding the intake manifold to the engine. Also loosen the hose clamp around the other center log. Beware, there is a solenoid bolted to the bottom of the manifold. It is pictured above with red circle. It is held by either E10 TORX or 10mm bolt.
Carefully, remove the intake manifold, being mindful of open intake ports. Afterwards, you can tape up the ports to be safe during the whole project.

In order to get the airbox out, we have take apart the driver side intake vent and snorkel assembly. The vent cover is clipped into the car body as pictured below. Gently pry up on the round clips on the car while gently pulling out on the cover.



Now that we have the driver side Intake Manifold out of the way and the intake ports taped up, it is time to see roll the sleeves up and get that airbox out of there.

We'll need to cut the airbox into two pieces in order to pull it out of the engine bay. The picture below shows where it should be cut. Saw-Zaw will do the trick here.



Here's a picture of the Saw-Zaw in action.



Once the "neck" of airbox is cut off, we can go ahead and unbolt the airbox from the car. It is held by 1 clip(inside airbox, towards the back of the car) and 1 -10mm bolt up top (towards the front of the car) and 1 - 10mm bolt under the box (accessible from under the car).

Once the airbox is removed, we should have something like this.



With the airbox out, we can begin modifying it. First, we need to modify the cover for MAF sensor. Something like this.



Then, we need to modify the airbox itself. We need to cut off the excess "neck" and cut a hole for the MAF housing to fit in the airbox. The following pictures should give you an idea about what I'm referring to.





In the end, we are shooting for something like this, with the MAF housing and cone air filter in the airbox.



That covers the airbox removal/modifcation. Before installing the modified airbox in the car, it would be a good time to install the oil feed line for the turbocharger. This involves, removing factory plug under the driver side fuel rail.

5mm Allen socket is needed to remove that plug. Before trying to break it loose, it's a good idea to "shock" the plug to break it loose. Take the Allen socket and lightly hammer the plug. This should help avoid stripping/ruining the Allen plug.

Once removed, be mindful of the factory crush washer on the plug. We will be re-using that crush washer with our TPC Racing oil feed line.

With the factory crush washer, install the oil feed line and feed it towards back of the car.

The installed oil feed line should look like this (with the airbox to the left and fuel rail on the right).



Let's cover installing the turbo drain fitting on the engine today. This process involves removing factory freeze plug on the passenger side and tapping the hole. It is highly recommended that you take your time with this part of the install.

We'll need to drain the oil from the engine. Replace the oil filter as well. Once all the drain plugs are tight, locate the freeze plug on the passenger side of the engine as pictured below.




Just like how we "shocked" the allen plug for the oil feed line, "shock" the freeze plug by lightly tapping it with a hammer. You'll need a small extension or screw driver that fits into the plug. DO NOT hammer or driver the freeze plug up into the engine.

Choose an appropriate drill bit size for your slide hammer and drill a hole into the freeze plug as pictured below. Note that you want to drill straight up, not at an angle. The drill in the picture below is at an angle and was included just to illustrate where you should drill.




Then, use your slide hammer to pull the freeze plug out.



Picture of the extracted freeze plug


Allow the remaining oil the drain out. You should have something like this.



We'll need a 1/2" - 14NPT tap for the next part. Use liberal amounts of grease on the tap to catch as much metal shavings as possible. CAREFULLY align the tap with the path of the hole. The first few turns are critical. Slight off-angle here will result in severely crooked fitting, or even worse, leaky fitting. Having a second person keeping an eye on the tap from a different angle is highly recommended.



Carefully run the tap in approximately 1/2". Run the tap back out and clean out the hole carefully. Thread in the provided TPC Racing turbo drain fitting. We want to be able to run the fitting in so that only about 2-3 threads are showing when we are done. You may have to run the tap in again. Repeat the process, until only 2-3 threads on the fitting are showing.





Before the final install of the fitting, make sure you clean out the tapped hole thoroughly. Apply some Loc-Tite or thread lock on the fitting and install the fitting into the engine. Do not over-torque it, we are looking for about 35 lbs/ft.

The 90* bend on the supplied turbo drain line will go to the engine side and the 45* bend on the line will go to the turbo when it's installed. So, we'll leave the line off for the time being.

Let's begin this post with assembly of intake assembly. Now, I will not cover installing larger injectors on the passenger side as it is pretty much the same process as the driver side, although you have less room this time and cannot lift the whole fuel rail like the other side. But since we have experience with the driver side and know how the injectors are installed into the fuel rail, it should not be too bad.

It is recommended that you remove the front engine cover, as this will give you a little more access to the fuel injectors. Take your time as this part of the install can get frustrating. You do not want to have to do this process again because of leaky injectors.

You can install the modified airbox in reverse order of removal. You can leave the air filter, MAF housing, and cover off for the time being.
We need to bolt the factory throttle body onto the supplied TPC Racing intake plenum. Use some gasket maker between the throttle body and the intake plenum. Then, we can go ahead and install the driver side intake manifold, fuel rail, intake plenum in reverse order of removal.

During the assembly of the we also want to install the 2 intake straps provided in the kit. Also, we need to install a check valve in the tank vent line to prevent the fuel tank from being pressurized. The check valve will go between the line and the vacuum fitting in the TPC Racing intake plenum. The vacuum fitting and the tank vent line is circled in the picture below.


We should end up with the top side looking something like this.


Before we install the red silicone boost hose, we need to make a small modification to the oil filler hose. We need to take the hose off on the engine side and trim about 1" (there's actually a small line on the hose that's a great reference) off. This will allow enough room for the boost hose to be fed down along the transmission.
The other end of that boost hose should end up somewhere above the passenger side axle, as pictured below. We may need to trim the boost hose slightly to make fine adjustments for fitment/clearance; however, we'll worry about that later.





We will be covering factory exhaust removal and installing TPC Racing exhaust and turbo components in our next post. I'll get it going with factory exhaust removal here.

First, the factory exhaust removal is pretty straight forward. We need to remove the factory muffler section along with all the exhaust brackets/clamps, For 986, we need to replace the factory headers with 987 headers or TPC Racing headers. As is the case here, for 987, we can use the factory headers. Be mindful of the vacuum line for the Sport Exhaust. It is clipped to the transmission as it is routed to the 2 valves. We also need to remove the cross support for the rear tray.

We should end up with something like this.


The underside of the car should look like this.


Installing Turbo Assembly
Let's get down to business and hang the turbo assembly on the car today. We got the factory exhaust system removed last time.

Couple of things to remember.
1) Do not tighten any hardware until you have all the hardware for that part started (threaded)
2) Use liberal amounts of Anti-Seize on all your hardware that will see extensive heat
3) Second pair of hands is highly recommended

Since the turbo bracket for our kit does not fit the 5sp transmission, we came up with a new bracket specifically for the 5sp. So, future installers will not have to modify the turbo bracket as 808croc had to.



I highly recommend that the turbo, bracket, and 3 exhaust components (pre-turbo) be assembled loosely on the ground. With help, slowly feed the 2 turbo pipes to the header flange and get some nuts&bolts started to hold the assembly up. Re-use the factory exhaust gasket between the headers and turbo pipes. At the same time, get the turbo bracket bolted to the tranny. Make sure you have all the hardware started by couple of threads before tightening things down.

This part of the install is not technical at all. It's mostly wrestling with the assembly, just like any other exhaust install.

Oil Drain Line
Now that turbo is hung, we can go ahead and connect the turbo system. Let's start with the oil drain line.
We will have to pull the undertray off and modify it, so that the oil drain line can pass through.



We'll need to eliminate the center area of black plastic ducting, as indicated by the white paint in the above picture. First, drill out the center rivet. Then, use mini Saw-Zall and/or cut-off wheel to cut out the center section. Make sure to smooth out the edges.
With the underbelly off, install the turbo drain line on the fitting we installed previously and onto the turbo drain fitting. The 90* end of the line goes to the engine side and the 45* end of the line goes to the turbo drain fitting. When working with line fittings, especially AN-fittings, you should always spray a little rust-penetrant on the threads to avoid damaging threads

 

Turbo Inlet
By this time, the airbox should be back in the car. We can install the supplied air filter with MAF/housing. You can feed the open end of the MAF housing through the modified airbox and connect the supplied corrugated Turbo Inlet hose onto the MAF housing using a hose clamp. Once, the hose is secured, you can put the airbox cover back on. Then, you can connect the MAF sensor through the hole in the cover.

You should have something like this (in the car)


We can now route the Turbo Inlet down to the turbo. In order to make room, we have to bend the slave cylinder line slightly out of the way. Basically, straighten one loop to give yourself enough line to tuck it up as pictured below. The section of line being relocated is circled in red.



With enough room, we can feed the Turbo Inlet down, connect it to the turbo with a hose clamp.


Oil Feed Line
We already installed the feed line during Airbox modification and should have the other end of the line accesible from the area of the turbo. In the picture above, you can see the oil feed line hanging there. Carefully route the line along the Turbo Inlet, securing them together with tie-wrap or two. Install the line onto the top of the turbo with some rust penetrant.

Vac/Boost line
Since we will not installing EBC (elec. boost controller), the wastegate only needs boost reference. This is accomplished by connecting the vac fitting on the compressor housing to the side fitting of the wastegate as pictured above.

Boost Hoses
I will not discuss installation of silicone boost hoses as it is pretty straight forward. Just be mindful of the axle. Additionally, use tie-wraps strategically to secure the hoses.













Some shots of the car on the dyno. We just got done with final test drive, so I'll edit those videos and get them posted.

 

Customer Testimony regarding this car...

"I was able to drive my brother's car (the LE boxster that TPC just worked on) quite a bit yesterday. I have a few friends with GTRs so we were able to run it with 2 gtrs. I have to say the car is like a different car. The job TPC did was absolutely amazing. The car runs so smooth it is honestly like it came from factory with the extra power.

The acceleration is so much stronger, we have done a few rolling to 60 runs in the mid to high 4s range already (this is without a launch, i suspect from a standing start with a good launch this car should run to 60mph in about 4 flat). For comparison sake, I took my Cayman (only has an intake and ecu upgrade) out last week with my friend's GTR and we did a few runs. With both cars starting in mid range 2nd gear I was smoked. We did a run where I ran 2nd gear and my friend ran 4th in the GTR and I only slightly kept in front. Yesterday, however, we ran my brothers car with the same gtr. Going 2nd gear vs 2nd gear we ran maybe 2-3 (at most) car lengths behind the gtr (which to me is very impressive considering the gtr is running ~ 500HP). We also ran 2nd gear in the Boxster vs 3rd gear in the GTR (again, I know it's the wrong gearing on the GTR but in fairness it still is putting out ~140 more crank HP than the boxster) and the boxster pulled on the gtr until they both hit 4th gear.

I cannot express how happy I am with the car, TPC is truly first class...their customer service (and I will say it again because it cannot be said enough) is truly amazing and the car feels like it was sent over right from Stuttgart...the quality of their work is truly second to none."



And

"So two weeks ago I dropped my LE 2.7L Boxster off at TPC for the LP Turbo system that they currently have for sale. Not that the car was not fun to drive before I dropped it off, but all I can say after driving it now is WOW. As I live in New York, the 200 mile drive back to the city may have been one of the quickest, most enjoyable rides I have ever gotten to experience in my car, it is honestly like a different car. The torque in the lower gears is just insane, and the revs pull so much faster to the redline, as the horsepower increase is apparent (using apparent doesn't even give this kit the justice it deserves). Even at highway cruising speeds in 5th gear (at about 2500 rpm), the car just pulls soo much harder than it ever did. Not to sound like a promoter for TPC, but they honestly did an amazing job and their customer service is incredible. Tom sent me daily emails updating me with pictures of the progress they were making on my car and responded to every single one of my questions within an hour of sending him an email. I couldn't be any happier with the job that everyone at TPC has done with the car. By the way, the exhaust note is one of the best sounding exhausts I have ever heard in a car; it even sounds a little bit like a CGT to me as it screams toward the redline. If you have a 2.7 and want to have more fun and more power with the car, I honestly don't think there is a better way to go.

Thanks again to everyone at TPC!"

 

Nice job Casey !! How is the kit for the Spyder coming along? Will you offer a low pressure kit as well? I see the 80/50 HP/Tq gains are great. What type of gains would you expect for the non low pressure kit?

Thanks,
pcw

 

Slowly but surely... Working on a 2.9L today. I would tend to believe the standard ATP:2 system would get us somewhere near the HP the 3.2L system churns out... Near 350whp.

Porsche 986 Boxster S Turbo System - TPC Racing



Casey