BRZ 86 Harrop Supercharger Kit

Author: Julius Bloem  Date Posted:3 September 2020 

BRZ / 86 Harrop Supercharger Review Alan's Supercharged BRZ / 86 demonstrates why the Harrop Supercharger kit is the best on the market. Possum Bourne Motorsport have previous experience with brands such as Bullet, Sprintex, HKS and Harrop.

Transform your Toyota 86 or Subaru BRZ by using the best Supercharger kit

We're no strangers to building and tuning the Toyota/Subaru 2-door platform. We've experienced the transformation and performance improvements that are possible with a range of modifications, including various superchargers and turbo kits. This article shows Alan's BRZ, which we believe is the best Supercharger option on the market.

Major 86/BRZ Projects

When the BRZ was first launched in 2012, Possum Bourne Motorsport partnered with Subaru Australia to build a promotional racecar – click here to view.
Later, we partnered with a client to build a complete racecar modelled off the original Subaru Australia build, this time with a supercharged race engine package. To achieve the power desired, we tested and modified a number of supercharger kits - click here to view.
In addition to these, we have serviced, modified and tuned many street and race orientated 86s and BRZs, including those with Bullet/Sprintex supercharger kits, HKS supercharger kits and Greddy turbocharger kits. 

Plan

The plan with Alan's BRZ was to create a high-performing sports car that produced serious power, had increased braking capability, was completelty road legal, and drove like stock. 

Alan was used to light nimble sports cars, previously owning a Lotus. Whilst he enjoyed his new BRZ, he knew it needed more, so reached out to PBMS to come up with a plan. A plan to make the car sound, look and drive like stock, but perform much better.

PBMS Stage 5 – Harrop Supercharger Kit

After copious amounts of research, the Harrop TVS1320 Supercharger kit was selected, simply because it was the best option; it was the highest quality, had an OEM appearance, high power capacity and well known for great reliability. 

Click here to find out more about the PBMS Stage 5 Pacakge.

Engine

This car has a completely stock engine. To protect the internals from the increase load, we opted to use a high quality Motul 8100 X-Max engine oil and Genune Subaru filter. Click here for oil, filter and maintenance products.

Exhaust

Inline with Alan's plan to keep the vehicle sounding stock, we opted to keep the stock headers and the exhaust system. There is no doubt replacing them with high-flow items would have increased power and torque, however keeping the noise and potential drone well under control was deemed more important on this build. Click here for exhaust systems and headers.

Cold Air 

Intake 

The Harrop Supercharger kit comes with a well designed and factory-looking cold air intake to feed the engine with cool air, aiding performance.​

Intercooler

A complete kit, the Harrop system comes with a water-to-air intercooler system with a bolt-on cooler that sits in the radiator duct. This is fed with quality Motul coolant to meet Harrop's recommendations. 

Fuel System

Impressively, the factory fuel system is able to keep up with the additional power this vehicle produces. Now these vehicles are starting to get a little older, PBMS recommend replacing or upgrading the fuel pump and fuel filter to ensure the engine is feed with a steady and safe supply of fuel. 

PBMS Tuned

This car has been PBMS tuned by our tuner on our rolling road dyno, then the tune validated on the road. Like all of the cars we tune at PBMS, we used the 9-step tuning method to gain the best results. Check out our 9-step tuning video so you can see what makes our tuning different from most other tuners. Special care was taken on this BRZ to get it driving as close to stock as possible, just with much more additional power. 

Brake upgrade

With the additional engine performance, a simple and effective plan to upgrade the aging factory brake pads and fluid was hatched. We selected a set of Endless SSM brake pads and Motul Racing Brake Fluid 650. This comination is perfect for the street, providing more than enough bite to match the supercharger without additional brake dust or noise.

Keeping it legal

Inline with Alan's goals to keep this car completely road legal, we went through the process of performing a LVVTA certification, which required the fitment of driveshaft safety loops after the serious power increase. With the LVVTA certification, this vehicle is 100% legal in its modified form and simply requires a regular WOF to maintain roadworthiness. 

Results

You’ve all been waiting to hear what the results are. We all know a stock 86/BRZ can be a blast to drive, albeit a little lacking in the power department. The modification package transformed the performance of this car.

Dyno Power

From stock, these cars produce around 125KW at the wheels (147KW at the engine), on a good day. Once modified and tuned 98 Octane fuel, this car produced 200KW at the wheels (235KW at the engine), making for a truly impressive 60% increase in power, across the board. Notably, a power run on the same vehicle on a cooler day netted a slightly higher 205KW at the wheels.

Supercharged Harrop Toyota 86 Subaru BRZ

Performance on the road

Reminisant of the factory powerband, it's very linear, yet smoother, with more power everywhere. As the revs climb, the power increase becomes further accentuated. At a lowly 4500RPM, it's already producing a similar power to a stock engine. Beyond that point, the vehicle surges forward, becoming increasingly rapid. 

How good does it sound?

Inline with the brief, this vehicle sounds very close to stock. A slight increase in induction noise is noticeably as the engine draws in a larger volume of air as the RPM climbs toward redline. 

Engine Bay

The smooth and stock-looking supercharger is a great addition to the engine bay, that could certainly go un-noticed by anyone not familiar with these vehicles. The technician that carried out the installation noted that the quality and fitment of this kit was the best he had ever experienced. 

Longevity 

This build was carried out in 2017. Since this time, we've seen Alan for 6-monthly servicing like clock-work, with out any faults or problems with the modifications. 

Alan did receive a re-call notice to have his valve springs replaced by our local Subaru dealership. During this process, PBMS worked with the dealership to remove and reinstall the Supercharger so they could complete their repair under warranty.

Did we achieve the goals?

Without a doubt. Both PBMS and Alan are incredibly impressed with the performance of this simple and effective setup.

How could we improve the setup

There are a few low-hanging fruit that could open up the performance of this vehicle a little more, to produce more power and torque. A set of high-flow headers, mid-pipe and cat-back exhaust would take it to the next level. Click here for exhaust systems and headers.

If we wanted to push the power a little harder, an E85 Conversion with a fuel system and tuning upgrade could be performed and coupled with a slight boost increase, where we would expect around 240KW+ at the wheels, close to a 100% increase in power level. This is nearing the limits of the factory engine, particularly the engine's connecting rods. We would recommend an engine build if wanting to push the limits and maintain long-term reliability. 

If the vehicle is going to be used on-track or pushed hard in the back roads, the oil system will need to be taken care of, with an oil-cooler kit and baffled sump or sump plate. We would also recommend increasing the thickness of the oil to increase oil pressure. 

As cooling can be an issue on these vehicles, and upgraded radiator should be considered also. 

Overall Performance

If you stepped out of a stock car and into this, you'd be blown away. With 60% more power the acceleration is rapid, whilst staying true to it's roots, retaining the factory drivability and linear power band. As the dyno sheet suggests, the most you allow the engine to rev, the quicker the car becomes. Approaching redline, the accelleration rate of the nimble chassis is nothing short of impressive. The result is a car that is incredibly easy to cruise around town, yet outstanding when you're able to experience the full throttle, high RPM performance. 

The simple and effective braking upgrade is perfectly matched, ensure the balanced feel that these vehicles are known for is kept in check - just better in every way!

Find out more about the Harrop TVS1320 Supercharger Kit.

Find out more about the PBMS Stage 5 Upgrade Package which includes the Supercharger Kit.

If you’re interested in having any of this work done to your car or you're after any parts, please don't hesitate to contact us.


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