4.0T V8, 720S, 720S Spider, bolt-on, Capristo, cat-bypass, catless, downpipes, ECU tune, exhaust sound, exhaust upgrade, Fabspeed, flat-plane V8, GCC, Kuwait, M840T, McLaren, mid-engine, power gains, race downpipes, Saudi Arabia, sport cats, Stage 2, supercar, turbo spool, twin turbo, UAE, YPG Motorsport - September 21, 2026

McLaren 720S Downpipe Guide — Catless Race Downpipes vs Sport Cats | M840T 4.0T V8 | Power Gains, Sound & Installation

The McLaren 720S is one of the most devastatingly fast supercars ever built — and its M840T 4.0-liter twin-turbo V8 is the reason. Producing 710 HP from the factory, the 720S already embarrasses cars costing three times as much. But the factory catalytic converters sitting directly downstream of each turbocharger create a massive restriction where exhaust gas velocity is highest. Replacing them with aftermarket downpipes is the single most effective bolt-on modification you can make to unlock the M840T's full potential.

This guide covers everything you need to know about upgrading the downpipes on your McLaren 720S: catless race downpipes versus sport cats, real-world power gains, exhaust sound transformation, fitment details, installation considerations, and why an ECU calibration is essential to extract the full benefit.

The M840T 4.0T V8 — Platform Overview

The M840T is McLaren's second-generation twin-turbocharged V8, displacing 4.0 liters and featuring a flat-plane crankshaft. It represents a complete redesign from the M838T that powered the 570S and 650S — with a larger bore, new cylinder heads, revised turbocharger compressor and turbine wheels, and significantly improved thermal management. The engine sits in a mid-rear longitudinal configuration in the 720S's carbon fiber monocell II chassis.

Factory power output:

McLaren 720S / 720S Spider — 710 HP / 568 lb-ft

The factory catalytic converters are dense ceramic-substrate units — typically 600+ cells per square inch — positioned directly downstream of each turbocharger. They create substantial backpressure at the point where exhaust volume and velocity are highest. Replacing them with aftermarket downpipes reduces turbo backpressure, improves spool response, lowers exhaust gas temperatures, and opens the door for the ECU to run higher boost and more aggressive timing.

Downpipe Options for the McLaren 720S

YPG Motorsport 720S Race Downpipes — $2,999.99

Purpose-built catless race downpipes for the McLaren 720S. Manufactured from 304 stainless steel with CNC-machined flanges, TIG welded, with all necessary hardware included for a complete bolt-on installation. These remove the factory catalytic converters entirely, providing:

Maximum exhaust flow — zero restriction from turbo outlet to mid-pipe
Fastest turbo spool — reduced backpressure lets the turbos build boost more efficiently
Most aggressive exhaust note — the flat-plane V8 scream becomes dramatically more pronounced
Lowest EGTs — removing the heat-generating catalyst element drops exhaust gas temperatures under sustained track use

Fabspeed 720S Cat-Bypass Pipes — $4,199

Fabspeed's cat-bypass solution for the 720S uses precision-mandrel-bent 304 stainless steel tubing to replace the factory catalytic converters. Fabspeed is an established name in exotic car exhaust systems with extensive McLaren fitment experience. The higher price reflects Fabspeed's brand positioning and their heat-shielding approach for the mid-engine bay environment.

Capristo 720S Sport Cats — $6,900

Capristo's sport catalyst option for the 720S retains a high-flow metallic substrate catalyst element while significantly reducing restriction versus factory. Capristo is a German manufacturer known for exotic car exhaust systems, and their 720S sport cats represent the premium end of the market. The trade-off:

Strong flow improvement over stock — significantly less restrictive than factory converters
Emissions compliance — a catalyst element is physically present for visual inspection
Refined exhaust character — less raw than full catless, more refined at cruise
Premium build quality — Capristo's German engineering and finish

The Bottom Line

For maximum performance, YPG Motorsport catless race downpipes at $2,999.99 deliver the best value — full catless flow at a fraction of the Capristo price. If you're in Kuwait, Saudi Arabia, Qatar, UAE, Bahrain, or Oman, go catless — there's no emissions testing, and you get maximum performance and sound. Capristo sport cats at $6,900 are the choice for owners who want flow improvement while retaining a catalyst element.

Real-World Power Gains

Here's what to expect at each stage of modification on the McLaren 720S:

Configuration	Estimated Crank HP	Estimated Crank Torque
Stock 720S	710 HP	568 lb-ft
Stage 1 ECU Tune (stock hardware)	770–800 HP	620–650 lb-ft
Stage 2 ECU Tune + Catless Downpipes	820–860 HP	670–710 lb-ft
Stage 2 + Downpipes + Intake	840–880 HP	690–730 lb-ft

Downpipes alone contribute roughly 20–35 HP on the M840T — but their real value is enabling the ECU calibration to safely run higher boost targets and more aggressive ignition timing. The combined hardware-plus-software gain from Stage 1 to Stage 2 is typically 50–60 HP.

At 860 HP, the McLaren 720S becomes one of the fastest cars on the planet — capable of sub-10-second quarter miles and 200+ MPH trap speeds with stock turbos and a bolt-on modification path.

Exhaust Sound — What Changes

The M840T is arguably the best-sounding turbocharged V8 in production. The flat-plane crankshaft gives it a high-revving, exotic character that most cross-plane V8s simply cannot match. But the factory catalytic converters muffle a significant amount of that raw character.

With catless downpipes:

An absolutely visceral exhaust note — the 720S goes from refined supercar to screaming race car
The flat-plane V8 scream at high RPM becomes intoxicating — a sound that rivals naturally aspirated Ferraris
Explosive crackles, pops, and bangs on overrun that echo off every surface around you
A deep, mechanical bark at full throttle that makes the hair on your neck stand up
Noticeable increase in cabin noise — the mid-engine layout puts the exhaust close to the cockpit, which most 720S owners consider a feature, not a drawback

With sport cats (Capristo):

Meaningful improvement over stock — deeper, more present at all RPMs
Less aggressive than catless — more refined, less rasp at highway cruise
Overrun crackle is present but controlled
Excellent for owners who want the performance without the full race car volume

The 720S with catless downpipes is, without exaggeration, one of the best exhaust notes in the automotive world. It's the modification that makes you take the long way home every single time.

Fitment — McLaren 720S Variants

The M840T downpipe configuration is shared across both 720S body styles:

McLaren 720S Coupe — 2017–2022
McLaren 720S Spider — 2019–2022

Both variants share the same engine, turbo configuration, and exhaust routing. All downpipe options listed in this guide fit both the Coupe and Spider with identical bolt-on installation — no cutting, welding, or fabrication required.

Installation Overview

McLaren 720S downpipe installation requires specialized equipment and McLaren experience:

Time: 3–5 hours for an experienced technician
Equipment: Vehicle lift with mid-engine access capability, standard hand tools, penetrating lubricant for exhaust hardware
Difficulty: Advanced — the mid-engine layout and carbon fiber monocell II chassis require careful handling. Access to the turbo outlet flanges requires removing specific body panels and heat shielding

The YPG Motorsport downpipe kit includes all necessary hardware — bolts, gaskets, and clamps — for a complete bolt-on installation. CNC-machined flanges match the factory turbo outlet mounting points precisely.

We strongly recommend installation by a McLaren specialist or an experienced exotic car workshop. The carbon fiber monocell II chassis and mid-engine packaging require familiarity with McLaren service procedures.

ECU Calibration After Installation

After installing aftermarket downpipes, an ECU calibration is strongly recommended. Without it:

The check engine light will illuminate from rear O2 sensor codes
The ECU will not adjust fueling or boost to take advantage of reduced backpressure
You'll have the hardware without the full performance benefit

McLaren ECU calibration options vary by model year and software version. Contact YPG Motorsport for platform-specific tuning availability for your 720S.

Why YPG Motorsport for Your 720S Downpipes

YPG Motorsport has been engineering high-performance exhaust systems since 2011 — and the McLaren platform is one of our fastest-growing categories. Our team holds the world record for the first sub-10-second W205 C63 quarter mile — 9.97 seconds at 828 WHP — demonstrating the engineering precision we bring to every platform we build for.

Every set of downpipes is manufactured from 304 low-carbon stainless steel, TIG welded, with CNC-machined flanges. They carry a lifetime warranty.

GCC stock is maintained for same-week dispatch to Kuwait, Saudi Arabia, UAE, Qatar, Bahrain, and Oman. Worldwide shipping is free.