The 2020-2022 GT500 arrives with 760 horsepower, 625 lb-ft, and a 0-60 of 3.4 seconds. Ford did the hard part. What Ford also did was leave restriction in the exhaust, a heat exchanger sized for a stock power level, and driveline components specified for exactly the output the car left with and not a pound more.
That is where the aftermarket earns its keep on this car. This guide covers the ten categories worth your money, what each one actually does, and where the supporting mods stop being optional.
1. Exhaust
Usually the first stop, and reasonably so. An aftermarket system reduces backpressure so the engine expels gases more effectively, and on a car making this much power the stock system is genuinely the restriction. You get a real note and a moderate power gain.
3" T304 stainless piping
4" black tips
X-pipe, polished and gunmetal also available
T304 stainless
High-flow cats keep it emissions compliant
The street answer
Maximum performance gain
Track use only
Not emissions compliant
If you want the cheapest meaningful exhaust change on this car, start further back. Our resonator delete X-pipe picked up 7 rwhp overall and a peak 16 rwhp at 6,645 rpm on a stock GT500, and it sounds considerably meaner. The full install and dyno results are in that write-up.
2. Body & Styling
Styling on this car is not purely cosmetic. Aerodynamic parts affect drag and downforce, which affects handling and stability at the speeds a GT500 reaches without trying.
Improves airflow under the car
Carbon fiber, light and strong
30-45 minute install
T25 Torx, 2.5mm Allen, trim tool
Sheds weight off the back of the car
Our own carbon fiber line
Under 10 minute install, no tools
2015-2017 version also available
The deck lid and bezels are ours. DX Carbon is the Lethal Performance carbon fiber line, covering hood vents, spoilers, mirror covers, splitters and more across the S550 and S650.
3. Performance Tuning
Every mod above and below this line is worth less without calibration. Tuning adjusts fuel delivery, ignition timing, and boost pressure so the parts you bolted on actually work together, rather than each one fighting the factory calibration's assumptions.
- Increased power and torque from the parts you already paid for
- Better drivability as the calibration smooths out what the mods disrupted
- Setup-specific optimization for street, drag, or track, switchable between profiles
Custom tune from Shoemaker for your mods
Remote tuning, no dyno appointment
Fuel mapping, timing, boost control
The shop that dyno'd our GT500 work
Both are worth a look, and both have deeper catalogs than the two listings above: Shoemaker Performance and Palm Beach Dyno. Lund Racing, Oz Tuning and ZFG Racing are also solid on this platform. For how remote tuning actually works and what a tuner needs from you, our Mustang tuning guide covers it end to end.
4. Heat Exchanger
The supercharged 5.2L cross-plane V8 generates enormous heat, and every power mod you add generates more. Without adequate cooling that heat leads to knock, reduced efficiency, and at the extreme, engine failure. The factory heat exchanger is sized for the factory power level.
Better airflow through the core
Prevents heat soak on long pulls
The first mod on a boosted car
5. Axles
Factory driveline components are specified for factory output. Raise horsepower and torque and the stock half shafts become the weak link, which shows up as driveline vibration, premature wear, and eventually a failure that takes other parts with it.
31-spline design
Far stronger than factory
Built for aggressive launches
6. Oil Catch Can
Oil vapor escapes the crankcase and circulates back to the intake, carrying particles that build up on intake valves and pistons. Over time that reduces efficiency and can cause knock or pre-ignition, which on a supercharged engine is not a small problem.
Clean side separator
Plug and play, no cutting
Clears the aftermarket blower
Get this one if you upgraded the supercharger
7. Fueling
As power climbs, the stock system stops keeping up. That produces a lean condition, and a lean condition on a boosted engine means knock, detonation, and damage. Fueling is not a performance mod, it is the thing that makes the performance mods survivable.
Complete kit: pumps, lines, filters, regulator
Built for heavily modified engines
A returnless system controls pressure adequately at stock demand. Once fuel demand swings dramatically, which is exactly what happens on a modified supercharged car, a return style setup is the difference between stable pressure and a tune your tuner has to leave margin in.
8. Induction
More air, especially cooler air, means more oxygen and better combustion. Induction is the best value-per-dollar category on this car after exhaust.
Cools the intake charge
No tuning required
+47 rwhp and +8 rwtq on the dyno
Built to support tuning and more boost
9. Supercharger & Pulleys
The two ends of the same idea. A pulley swap spins the factory supercharger faster for more boost, which is the cheap route. A larger supercharger moves more air fundamentally, which is the expensive one.
Reduces slip at higher boost
Straightforward swap, direct boost gain
Includes the install tool
Gates belt included
Latest twin-screw rotor profile and housing
The full send option
Frequently Asked Questions
What is the first mod I should do to a 2020 GT500?
Exhaust or induction for the cheapest real gain, but if you intend to add boost at all, do the heat exchanger first. Cooling is the constraint on this engine and it becomes the constraint the moment you raise output.
How much horsepower does a stock 2020 GT500 make?
760 horsepower and 625 lb-ft from the factory, with a 0-60 of 3.4 seconds.
Do I need a tune for GT500 mods?
For most of them, yes. Tuning is what makes the individual mods work together. Note that Lethal Performance does not write tunes; we point you to Shoemaker Performance, Palm Beach Dyno, or another tuner.
What is the cheapest way to make a GT500 sound better?
A resonator delete X-pipe. On our testing it also picked up 7 rwhp overall with a 16 rwhp peak gain at 6,645 rpm, which is more than resonator deletes usually give.
Do I need upgraded axles on a GT500?
If you are adding meaningful power or launching the car hard, yes. Factory half shafts are specified for factory output, and they are the common failure point once that changes.
Pulley swap or bigger supercharger for a GT500?
A pulley swap spins the factory blower faster for more boost and is the cheaper path. A larger supercharger like the Whipple 3.8L moves more air fundamentally and supports much higher output. Either way, the supporting mods come first.
Why does a GT500 need a return style fuel system?
A returnless system controls pressure fine at stock demand. On a modified supercharged car fuel demand swings hard, and a return style setup holds pressure stable so the tuner does not have to leave safety margin on the table.
Are catless headers legal on a GT500?
No. The Kooks off-road connection kit is track use only and not emissions compliant. If the car sees the street, use the Stainless Works catted headers instead.
Keep Reading
760 Was the Starting Point
Cooling and fueling first, boost after. Call us and we will build the list in the right order instead of the fun order.
