Mercedes CLA Class C117 (2013-2019) CLA45 (2013-2015) Mercedes A/CL/GLA45 Turbo Blanket (M133 Engine 355/376 BHP) - FORGE MOTORSPORT FMTUBL9

FORGE Motorsport FMTUBL9 is a turbo blanket designed specifically for the Mercedes-AMG M133 2.0-litre turbocharged engine, used in early CLA45/A45/GLA45 applications.

What does the turbo blanket actually do?

Think of the turbocharger as a very hot energy converter sitting beside the intake and engine hardware.

The exhaust side of the turbo can reach extremely high temperatures. A turbo blanket wraps the turbine housing with a high-temperature insulating material, reducing the amount of radiant and convective heat escaping into the engine bay.

Basic thermal philosophy:

Exhaust gas → Turbine → Turbo housing → Engine bay

Without insulation:

🔥 Turbo housing radiates heat → intake piping / wiring / surrounding components absorb heat

With the blanket:

🔥 Turbo housing → thermal barrier → substantially less heat radiated outward

The objective isn’t simply “make the turbo hotter.” The objective is to keep heat concentrated where it is useful while reducing unwanted heat transfer to the surrounding engine bay.

Why it matters on the M133

The M133 is a particularly interesting application because Mercedes-AMG extracted substantial output from a relatively compact 2.0-litre four-cylinder.

Early CLA45/A45/GLA45 versions produced approximately 355–376 hp depending on model/year/market, meaning the turbocharger and exhaust system operate under significant thermal load.

A turbo blanket can potentially provide several benefits:

Area	Potential effect
Turbo housing	Reduced external heat radiation
Engine bay	Lower local heat exposure
Intake system	Less unwanted heat soak
Wiring/hoses	Reduced thermal exposure
Turbo response	Potentially improved thermal energy retention
Under-bonnet temperature	Potential reduction around turbo area
Track use	More useful than during gentle street driving

The interesting engineering point

The biggest misconception is:

Turbo blanket ≠ horsepower modification.

It doesn’t suddenly increase airflow or compressor efficiency.

Instead, it is a thermal-management modification.

For a high-output M133, that distinction matters.

A turbocharger works by extracting energy from exhaust gas. If thermal energy is unnecessarily dumped into the engine compartment, you’re creating a heat-management problem.

The blanket attempts to manage that thermal energy more intelligently.

Where it fits in a serious M133 build

For a mildly modified CLA45, I’d think about the thermal system as a chain:

Turbo blanket
↓
Downpipe / exhaust thermal management
↓
Intercooler
↓
Charge-air temperature
↓
ECU calibration
↓
Repeatable power

This is why thermal management becomes increasingly important as you move from stock → Stage 1 → Stage 2 → track/high-boost setup.

A powerful turbo system that repeatedly heat-soaks can become less consistent even if its peak dyno number looks impressive.

FORGE FMTUBL9 — the real purpose

The FMTUBL9 should therefore be viewed as a supporting performance component, rather than a direct power-adder.

Its philosophy is:

Control where the M133’s enormous exhaust-side heat goes.

For a CLA45/A45/GLA45 used aggressively, that can be more valuable than chasing another small bolt-on horsepower gain.

In engineering terms: the turbo blanket is not trying to make the turbo bigger. It’s trying to make the thermal environment around the turbo smarter.

Mercedes CLA Class C117 (2013-2019) CLA45 (2013-2015) Mercedes A/CL/GLA45 Turbo Blanket (M133 Engine 355/376 BHP) - FORGE MOTORSPORT FMTUBL9

 

Remus GPF Cat-Back Exhaust for Audi S3 GY | 4x 102mm GT Titanium

The REMUS GPF-back system for the Audi S3 8Y/GY is essentially an upgraded exhaust path after the gasoline particulate filter (GPF). That is important because it changes the exhaust character and flow without removing the GPF itself.

REMUS lists the 8Y S3 system with 76 mm tubing versus the original 70 mm, with a resonated front section, sport rear silencer, quad outlet tubes and selectable 102-mm tailpipes. 

What the system actually does

OEM S3:

2.0 TFSI → Turbo → GPF → OEM exhaust → mufflers → 4 outlets

REMUS GPF-back:

2.0 TFSI → Turbo → GPF → 76-mm REMUS section → resonator → sport silencer → 4 × 102-mm tips

The GPF remains upstream, so this isn’t the same as deleting the emissions equipment.

Why the 76-mm pipe matters

The diameter increases from approximately 70 → 76 mm. That gives roughly 18% greater cross-sectional area:

A = D^2 

(76/70)^2 ~1.18

So the exhaust has substantially more flow area, although 18% more area does not mean 18% more horsepower. 

The actual power effect depends on the turbo, GPF restriction, muffler design, ECU calibration and operating point.

REMUS describes the system as offering improved performance/torque, sporty sound and weight optimisation. 

The interesting part: 4 × 102-mm GT Titanium

The GT Titanium tips are primarily the visual and thermal character of the system. The large 102-mm outlets give the S3’s rear a much more aggressive appearance, while the titanium finish provides the motorsport-style appearance.

The REMUS catalogue also offers 102-mm carbon/titanium-internal versions, while the conventional 102-mm options include angled and straight-cut configurations. 

GPF-back vs cat-back

Technically, GPF-back is the more precise description for this S3 application.

It means the GPF remains untouched:

Turbo → GPF → REMUS exhaust

That’s different from a traditional “cat-back” system where the catalytic converter remains but the terminology refers to everything downstream of the catalytic converter.

Resonated vs racing configuration

For a road-oriented S3, the resonated, EEC/ECE-approved configuration is particularly significant. REMUS offers a resonated GPF-back system for the 8Y with approval and states that installation uses the original mounting points without vehicle modifications. 

There is also a RACING configuration. REMUS explicitly states that the Racing GPF-back version has no EEC approval, so it is intended differently from the approved road configuration. 

Engineering view

The key isn’t simply “bigger pipe = more power.”

The real engineering objective is:

Turbo outlet → GPF → pressure management → pipe velocity → resonator → muffler absorption → outlet

A good exhaust must reduce unwanted back-pressure without destroying exhaust-gas velocity, acoustic control or low-speed drivability.

For the S3’s 2.0 TFSI, the REMUS system therefore makes most sense as a supporting modification to an otherwise staged build rather than expecting the exhaust alone to transform the engine.

In one sentence:
The REMUS system turns the S3 8Y’s post-GPF exhaust from a relatively restrictive OEM acoustic/flow system into a larger 76-mm, resonated performance exhaust with four 102-mm GT-style outlets, while retaining the GPF in the approved configuration. 

Remus GPF Cat-Back Exhaust for Audi S3 GY | 4x 102mm GT Titanium

HKS CAPACITY UPGRADE KIT 3.4L KIT FOR TOYOTA 2JZ-GTE 21004-AT001

 

HKS CAPACITY UPGRADE KIT 3.4L KIT FOR TOYOTA 2JZ-GTE 21004-AT001

The HKS Capacity Upgrade Kit 3.4L for 2JZ-GTE (21004-AT001) is essentially a complete high-performance stroker bottom end. 

It doesn’t merely “increase the engine size”; it replaces the major rotating components so the 2JZ can make substantially more torque and support very high power. 

HKS developed it with drag racing in mind. 

What changes?

The stock 2JZ-GTE is approximately:

86 mm bore × 86 mm stroke = 2,997 cc

HKS changes it to:

87 mm bore × 94 mm stroke = 3,353 cc

So you get roughly 3.35 L, commonly called a 3.4L 2JZ. 

What’s inside the kit?

1. 87-mm forged pistons

The pistons use HKS’s nickel-plating treatment around the crown/top-land area, intended to improve resistance to knock, high combustion pressure and top-land deformation. HKS also specifies a molybdenum coating. 

2. 94-mm billet crankshaft

This is the heart of the displacement increase.

Stock:

86-mm stroke

HKS:

94-mm stroke

The HKS crank is fully counterweighted. 

3. H-beam connecting rods

The longer stroke requires an appropriately engineered rod/piston/crank combination. HKS supplies high-strength H-beam rods as part of the complete kit. 

Why make a 2JZ bigger?

This is the important engineering philosophy.

Imagine two engines both producing 1,000 hp:

3.0L 2JZ

The turbo has to force a lot of air into 3.0 litres.

3.4L 2JZ

The engine naturally moves about 13% more displacement.

That means the larger engine can produce substantially more airflow and torque for a given boost/turbo combination.

The objective isn’t simply:

“More displacement = more horsepower.”

It’s:

More displacement → more airflow → more torque → less dependence on extreme boost for a given output.

HKS specifically describes its capacity-upgrade philosophy as increasing displacement to produce more low-speed torque and help the turbocharger produce performance. 

Why is this interesting for your E46 2JZ idea?

This is where it gets seriously interesting.

A hypothetical:

E46 + 2JZ-GTE 3.4L

would be very different from a normal 3.0L 2JZ swap.

You would have:

3.35L

↓

large turbo

↓

huge airflow

↓

very high torque

↓

light E46 chassis

The danger isn’t necessarily the engine.

The drivetrain and chassis become the next engineering problem.

You’d need to think about the entire chain:

3.4L 2JZ

→ gearbox

→ clutch

→ prop shaft

→ differential/LSD

→ half-shafts

→ tyres

→ suspension

→ brakes

→ cooling

rather than treating the HKS kit as a standalone horsepower upgrade.

And there’s an important catch

The HKS kit requires cylinder boring/honing. HKS specifies the 87-mm bore and notes that individual blocks may require additional clearance/recess work. 

HKS also gives a 7,500 rpm recommended limit for this kit. Its published in-house result was approximately 1,015 PS and 110 kgf·m, but that is a manufacturer test result, not a guarantee that every engine built with the kit will safely produce that output. 

So this is not a “bolt it in and make 1,000 hp” kit.

It’s the foundation for a properly engineered high-output 2JZ.

In one sentence:

The HKS 3.4L kit turns the 2JZ from a 3.0L high-boost monster into a 3.35L large-displacement turbo platform—giving the turbo more engine to work with, substantially increasing torque potential, while replacing the pistons, rods and crank with components designed for the increased displacement and high-output application. 

For your E46 project, the fascinating question is actually 3.4L HKS 2JZ vs 3.0L B58: the 3.4L 2JZ has a very different torque-generation philosophy from the B58, even before you choose the turbo.

HKS CAPACITY UPGRADE KIT 3.4L KIT FOR TOYOTA 2JZ-GTE 21004-AT001