Upgrading your car with custom car parts goes far beyond bolt-ons and basic tweaks.
For enthusiasts who value speed, handling, and bold styling, the right carbon fiber components—engineered for model-specific fit and measurable gains—can dramatically transform performance and presence.
We’re breaking down the ten parts that deliver the biggest impact for serious drivers who demand true improvement, not just appearance.
1. Carbon Fiber Full Body Kit
Serious enthusiasts demand transformation, not just tweaks. If you want a unified, effective approach to appearance and aerodynamics, a carbon fiber full body kit outperforms piecemeal upgrades on every level. You get an instant leap in style, presence, and real-world performance advantages.
Why carbon fiber full body kits set the benchmark:
- Pre-preg dry carbon cuts weight by up to 60% vs steel and delivers stiffness that holds shape at full speed.
- UV-stable clearcoat locks in rich gloss and prevents yellowing or fading, keeping your car sharp for years.
- Model-specific designs mean perfect gaps, no rattling, and a true bolt-on fit.
- Kits streamline underbody airflow, drop lift, and bring high-speed stability that piecemeal parts can’t match.
Drivers who want function and factory-level fitlove the ASM Design BMW G82 M4 Full Carbon Fibre Kit. It pulls together splitter, side skirts, diffuser, and spoiler into one aerodynamic system with OEM precision, but trimmed weight and race-focused construction. If you’re building for track or show, start with a full kit that integrates seamlessly, like ours: BMW G82 M4 Full Carbon Fibre Kit – ASM Design.
Explore the full-vehicle kit range: Full Body Kits.
The fastest path to high-speed stability is through a complete, tested aero system—piecemeal won’t cut it at the limit.
Key Advantages of a Carbon Fiber Full Body Kit
- Pre-preg dry construction is lighter and stiffer than wet carbon or ABS. You get both track-ready durability and reliable fit.
- Careful mold tooling ensures alignment and gap tolerance that matches (or beats) stock panels.
- Extended warranties—often up to 24 months—back high-end kits.
- Real-world aero numbers: Kits like ours are validated with CFD and wind-tunnel data, so you’re not guessing on gains.
Want aero that doesn’t just look good but nails performance? Full-system kits are essential.
2. Carbon Fiber Front Splitter
Think first-step aero upgrades. The front splitter gives a crisp steering response and sharper looks. Aggressive, but practical when designed correctly. You want real downforce, not just looks.
What makes a great front splitter?
- Pre-preg carbon construction holds shape and refuses to flex at speed. This matters for true downforce.
- Hardpoint mounting keeps parts tight, no rattle, no wasted energy.
- Design should extend where pressure is highest, but keep ground clearance practical for real-world use.
You want a noticeable, immediate shift in front-end feel. Front splitters paired with proper bracketry deliver quick steering, predictable grip through corners, and a more aggressive profile.
Before installing:
- Check ground clearance on your routes. Choose a design tested for your chassis.
- Always reinforce mounting points to avoid flex or detachment at speed.
- Use ASM Fitting Guides for step-by-step clarity.
3. Carbon Fiber Rear Diffuser and Spoiler
Balance is everything. Properly balancing your aero upgrades means more confidence at high speed, not just a trick appearance. A carbon fiber rear diffuser smooths underbody air, while a purposeful spoiler cuts lift and wake turbulence.
Tactical gains from diffusers and spoilers
- Purpose-designed tunnels under the diffuser accelerate airflow, creating a pressure drop that plants the rear of your car.
- UV-topped pre-preg carbon holds visuals and performance season after season.
- Opt for model-specific mounting to prevent vibration and maintain trunk sealing.
Pairing a rear diffuser and spoiler together means more mid-corner grip, increased stability as speed climbs, and a true track-inspired silhouette. Combine the right tunnel geometry with a spoiler tailored for your driving—low for the street, more aggressive for track.
ASM carbon aero is always CFD-verified, model specific, and covered under warranty that stands behind extended, hard use. Explore the ASM carbon warranty: ASM Warranty.
When front and rear aero are balanced, handling sharpens and confidence grows mile after mile.
4. Valvetronic Cat-Back Exhaust System
Every build deserves more than just a louder note. Valvetronic cat-back exhausts boost flow, free up power, and let you control sound whenever you want.
Power and Flexibility
You want gains you can feel:
- TIG-welded T304 stainless systems withstand heat cycles and corrosion.
- Valves switch from stealth to sport at the press of a button or a change of drive mode.
- Smart tip design pairs well with wider carbon diffusers, dialling up presence from every angle.
Expect a crisper throttle, stronger midrange, and sound that wakes up at your command—but goes quiet when needed. Pairing with high-flow downpipes and a tune delivers even greater gains.
Ready for total clarity on how exhausts drive performance? See our horsepower and sound guide: Exhaust Guide.
ASM exhausts are backed with an industry-leading warranty: Exhaust Lifetime Warranty.
5. High-Flow Downpipes With Sport Cats or De-Cat
Modern turbo platforms live or die by the flow of their downpipe. Move to a high-flow downpipe and you immediately unleash faster spool, more torque, and an assertive new tone.
What matters in a true performance downpipe?
- 304L stainless, 2.0 mm thick for strength over big heat cycles
- Mandrel bends and smooth transitions—no sharp edges to kill flow
- 200-cell sport cats for road legality, de-cat for track
Best fit for turbo drivers planning a tune or chasing every ounce of torque—especially on S58 and S55 BMW platforms. Our ASM Performance S58 downpipes set the benchmark for fit and finish, ensuring everything lines up and seals tight.
Just remember: Always check your local rules for emissions. Use new gaskets, torque everything to spec, and protect O2 wiring from heat.
6. Forged Monoblock Wheels
Drop unsprung weight, ramp up handling, and sharpen every input: That’s the payoff with forged monoblock wheels. No cast wheel comes close.
You want speed, safety, and flawless stance. Forged wheels in 6061-T6 aluminum offer up to 30% less weight and massive strength compared to cast. CNC machining clears big brakes and fits tight.
Why forged monoblocks are best for serious builders:
- Hub-centric, model-specific machining prevents vibration and maximizes brake clearance.
- Tailored diameter, width, and offset put your car right where you want it—flush, but never rubbing.
- Corrosion-resistant finishes with a reliable, deep clearcoat.
See how ASM Forged Wheels deliver on every detail: ASM Forged Wheels.
Follow the right spec process:
- Start with target tire, then shape wheel diameter and offset.
- Validate brake clearance, keep rolling diameter tight for speedometer accuracy.
- Clean and torque properly, re-torque after 100 miles.
Wheels matter. Choose forged. Every launch, corner, and stop will feel the difference.
ASM wheels include a 5-year defect warranty for total confidence: Warranty Details.
7. Performance Tires
Your car’s grip starts (and stops) here. Advanced custom parts mean nothing without tires that keep everything glued to the pavement.
Proper tire choice unlocks every upgrade. Radically better turn-in, braking, and overall control. The right tire transforms how your car responds at the limit.
Choosing the Best Tire Compound
- UUHP summer tires give maximum grip and sharpest feedback. If you love late braking and cornering hard, these are your tool.
- UHP all-seasons work for all-weather builds, giving up a bit of ultimate grip for daily flexibility.
- Sidewall strength matters. Stiffer carcasses deliver crisp turn-in and reduce flex under load.
- Wider sections increase contact, but always match to wheel offset and suspension range to avoid rubbing.
Maintain correct pressure, track heat cycles, and rotate often for consistent performance. If you want to own your next lap time—or own the street—your tires must be as serious as the rest of your setup.
No other upgrade makes every system work harder, smarter, and safer than top-tier tires.
8. Adjustable Coilover Suspension
Handling begins and ends with control. Adjustable coilovers let you set your car up for track, street, or anything in-between. They’re not just about ride height. They’re about complete command of how your build behaves at the edge.
What to Look For
- Monotube dampers and true independent rebound/compression adjustments. Fine-tune your setup for any surface.
- Camber-adjustable top mounts give you faster response and sharper turn-in.
- Corrosion-resistant housings handle rain, salt, and track grime season after season.
Start with manufacturer specs. Log adjustments in small steps and test on the same stretch of road. A few clicks can totally transform feel. Once you find your sweet spot, lock it in. Real performance means tuning—then re-tuning—until the car matches your style.
Plan for follow-ups. Always check bump steer and align after lowering. Corner weight your car for maximum balance.
Rapid-Fire Coilover Tips
- Confirm wheel/tire clearance at full droop and compression.
- Use to fine-tune aero rake for maximum effect with splitters and diffusers.
- Inspect locking collars and top mounts after heavy use.
9. Big Brake Kit
Fast is easy. Stopping fast, lap after lap, is where great builds stand apart.
Big brake kits give you strong, repeatable stops and incredible thermal capacity—crucial for bigger power and harder driving. Multi-piston calipers evenly clamp larger pads, while two-piece rotors chew up heat so you never have to let off.
Key Considerations
- Fixed calipers bring rapid response and serious bite.
- Two-piece rotors cut rotational mass and stay cooler under abuse.
- Stainless braided lines and high-temp pads complete the system.
- Street pads for everyday. True track compounds if you run serious sessions.
Brake fitment matters. Always template your kit to the wheel and check airflow for proper cooling. Don’t forget about front/rear balance or ABS compatibility—changing either can shift your brake bias.
Brakes are the safety net for your power, grip, and aero. Never underestimate their impact.
10. Cold Air Intake System
A sealed, well-designed intake drops intake temps and improves response. While gains from intake alone are moderate, pair it with freer-flowing downpipes and a cat-back for real results.
Well-chosen intakes bring induction noise alive. Your throttle wakes up, and every squeeze feels more immediate. But quality matters: sealed units, smooth piping, and dependable filter media prevent heat soak and air leaks.
Intake Tips for Enthusiasts
- Always select sealed, heat-shielded systems to shut out engine bay heat.
- Stock MAF sensor locations keep your car running right—no warning lights, just clean power.
- Combine with exhaust and ECU tune for maximum effect.
Check fit, clamp everything tight, and monitor for any odd sounds after install. The right intake sharpens the whole experience.
How to Choose Custom Car Parts That Fit, Perform, and Last
Upgrades carry risk. We get it. You want aero, wheels, and performance parts that fit perfectly, do what they promise, and survive the daily grind.
Start with a plan. Think system: airflow in, exhaust out, tires down, suspension tuning, bodywork managing air, brakes dumping heat. Each part should support the next. Prioritize upgrades that unlock gains everywhere, not just in isolation.
Proven Steps for Picking the Right Parts
- Always confirm model, year, engine, and trim before ordering.
- Match tire width, wheel offset, and brake templates before you buy.
- Get precise with ride height, aero clearances, and splitter angles for daily needs.
- Pick pre-preg dry carbon for stiffness and lightness if you take track days or pride in show-level style.
- Use T304 stainless for exhaust longevity and forged aluminum for safe, strong wheels.
Choose dual-mode exhausts for real-world livability. Align spring rates and damping for your driving and surface. Make sure emissions gear stays legal where you live.
Professional installation makes the difference. Use supplied hardware, follow torque specs, and re-check everything after the first session.
We always support you with clear fitting guides and true 24/7 help if you get stuck.
Buying from authorized dealers means you get warranty confidence and fast help if something ever slips through.
Explore full carbon kits for focused builds: ASM Full Body Kits
Pair valvetronic cat-backs with downpipes for real turbo snap: ASM Performance Downpipes
Get forged wheels made to your spec: ASM Forged Wheels
See our network: ASM Authorized Dealers
Every part should build into your goals. Pick upgrades that bring the dream closer and keep your car on the road (and track) for the long haul.
Conclusion
Successful builds are the result of smart choices, not random bolt-ons. If you want gains you can genuinely feel—and show off—plan your upgrades, prioritize fitment, and focus on engineered, tested parts that stack real advantages.
We design, test, and support every part to help you unlock higher performance and better style all at once. When you’re ready to move from “someday” to “done,” lean on our experience, deep guides, and product lineup. Upgrade in a way that brings your ultimate car closer—every single day.
