The Datsun 510 is a classic car that has captured the hearts of automotive enthusiasts for decades. Under its modest sheet metal lies a platform with serious potential, and one of the most effective ways to unleash that potential is by upgrading the exhaust system. In this article, we will explore the benefits of installing a Midas Performance Kit, which can help achieve gains of up to 15 horsepower. We’ll also walk you through the installation process, discuss performance tuning, and answer common questions to ensure you get the most out of your vintage Japanese sport sedan.

Why Exhaust Upgrades Matter for the Datsun 510

The factory exhaust system on a Datsun 510 was designed for quiet operation and cost efficiency, not maximum power. Its narrow tubing, restrictive mufflers, and multiple bends create significant backpressure that chokes the engine’s ability to expel spent gases. When the engine can’t breathe out efficiently, it can’t breathe in fully, which directly limits horsepower and torque.

Upgrading to a performance exhaust system addresses this bottleneck. By increasing pipe diameter, smoothing flow paths, and using high-flow mufflers, you reduce backpressure and allow the engine to scavenge exhaust gases more effectively. The result is a noticeable improvement in throttle response, mid-range torque, and top-end horsepower. For the Datsun 510’s L-series or aftermarket engine, a well-designed exhaust upgrade can yield anywhere from 10 to 20 horsepower, with the Midas Performance Kit targeting a solid 15 HP gain.

Beyond power, a performance exhaust also changes the car’s character. The stock exhaust note is subdued; a kit like Midas unleashes a deeper, more aggressive tone that matches the car’s sporty heritage. It’s a sensory upgrade that makes every drive more engaging.

The Midas Performance Kit: What’s in the Box

The Midas Performance Kit is engineered specifically for the Datsun 510, meaning it bolts onto the factory manifold or a compatible header without major modification. The kit typically includes:

  • Mandrel-bent tubing – Smooth bends preserve exhaust velocity and prevent turbulence.
  • High-flow catalytic converter (optional) – For street-driven cars that need to meet emissions standards.
  • Performance muffler – Designed to reduce backpressure while producing a sporty exhaust note.
  • Hardware and hangers – Everything needed to mount the system securely.

Midas uses stainless steel or aluminized steel depending on the kit version. Stainless steel offers superior corrosion resistance and a longer lifespan, making it ideal for daily drivers and show cars alike. The kit is also engineered to work with the Datsun 510’s rear suspension clearance, avoiding contact with the axle or leaf springs during articulation.

Installation Preparation and Safety

Before you start wrenching, gather the right tools and create a safe workspace. Here’s what you’ll need:

  • Socket set (metric, typically 10mm, 12mm, 14mm, and 17mm)
  • Wrench set (combination wrenches or ratcheting wrenches)
  • Jack and jack stands (or a lift if available)
  • Penetrating oil (like WD-40 or PB Blaster) to loosen rusted bolts
  • Exhaust hangers (if not included in the kit)
  • Safety glasses and gloves
  • A hacksaw or reciprocating saw (if you need to cut stubborn bolts or old pipe)

Safety first: Never work under a vehicle supported only by a jack. Always use jack stands rated for at least double the car’s weight. Also, allow the exhaust system to cool completely before working near the manifold or catalytic converter – they can cause severe burns.

Step-by-Step Installation Guide

Step 1: Prepare the Vehicle

Park the Datsun 510 on a level surface. Lift the rear or the entire car using a jack, then place jack stands securely under the frame rails (not the floor pan). Ensure the vehicle is stable before proceeding. If you’re also replacing the header, you may need to lift the front as well. Disconnect the negative battery terminal to avoid accidental shorts or electrical issues.

Step 2: Remove the Old Exhaust System

Start by spraying penetrating oil on all bolts and nuts connecting the exhaust to the manifold, hangers, and flanges. Wait 10-15 minutes for the oil to work. Using your socket set and wrenches, carefully remove the existing exhaust system. Begin at the manifold: unbolt the downpipe or header collector from the manifold. Then work your way back, disconnecting hangers, clamps, and any mid-pipe connections. If the system is seized, you may need to cut the old pipe. Take care not to damage the manifold studs (replace them if they’re corroded).

Step 3: Inspect and Prepare Mounting Points

With the old system removed, inspect the mounting brackets and hanger positions. The Datsun 510 uses rubber hangers that can dry out and crack; consider replacing them with new ones for a snug fit. Clean the manifold flange surface with a wire brush and a rag to ensure a good seal. If you’re upgrading to a header, now is the time to install it, following the manufacturer’s torque specifications.

Step 4: Install the Midas Performance Kit

Begin by loosely fitting the header or downpipe to the manifold. Do not tighten fully yet. Work your way back, attaching the mid-pipe (and catalytic converter if included) to the header, using the supplied gaskets and clamps. Each section should be loosely joined. Then install the muffler and tailpipe section, routing it through the hangers. The Midas kit is designed to align with the stock hanger locations, but you may need to adjust the rubber hangers to eliminate contact with the chassis or suspension.

Once all sections are in place, go back and tighten all bolts, clamps, and flanges progressively. Use anti-seize compound on the bolts to make future removal easier. Check that the exhaust is not touching any heat-sensitive components like brake lines, fuel lines, or the chassis itself. Leave at least half an inch of clearance wherever possible.

Step 5: Check for Leaks and Verify Fitment

With the installation complete, start the engine and let it idle. Listen for any hissing or sputtering sounds that indicate a leak at a flange or joint. You can use a piece of cardboard or a rag held near connections to feel for escaping exhaust. Shut the engine off and tighten any loose connections. Also, bounce the rear of the car to simulate suspension travel and ensure the exhaust doesn’t rattle against the floor pan or axle. If you hear contact, adjust the hangers or add spacers.

Tuning and Performance Expectations

After installation, you’ll notice an immediate difference at start-up: the exhaust note is deeper and more aggressive. On the road, the car should feel livelier, especially in the mid-range (2,500-4,500 RPM). The 15 HP gain quoted by Midas is attainable when paired with a free-flowing air intake and a properly tuned carburetor or fuel injection system.

However, an exhaust upgrade alone doesn’t automatically deliver maximum gains. The engine will now breathe more freely, but its air/fuel mixture and ignition timing may need adjustment. On a stock Datsun 510 with a Hitachi or Weber carburetor, you may need to re-jet the carb to run slightly richer to take advantage of the improved flow. If your car has an aftermarket ECU or timing computer, a retune can further optimize the power curve.

Expect a 2-5 mpg improvement in highway fuel economy if you keep your foot light, but the real reward is the thrill of a sporty exhaust note and sharper throttle response. The Datsun 510 with a Midas exhaust becomes more engaging to drive, with a sound that turns heads at car meets and on mountain roads alike.

Common Questions About Datsun 510 Exhaust Upgrades

Will a performance exhaust make my car too loud?

The Midas Performance Kit is designed to be aggressive but civilised for street use. It is louder than stock but typically stays within legal limits in most areas. If you need to comply with a specific decibel regulation, you can add a resonator or keep the catalytic converter in place. For track-only cars, an open downpipe option exists, but that will be significantly louder.

Do I need to upgrade other parts to get the full 15 HP?

For best results, pair the exhaust with a cold-air intake or a sport air filter and a set of headers (if the kit includes them). A mild camshaft upgrade and a proper engine tune will further unlock power. The exhaust itself is a foundational mod – combining it with intake and ignition upgrades multiplies the gains.

How long does the installation take?

For a DIY mechanic with basic tools, plan on 3-5 hours. Rusted bolts and seized hardware can extend the job. Lifting the vehicle, crawling under, and dealing with tight spots on a vintage car requires patience. Allowing extra time for penetrating oil to work is wise.

Is the Midas kit compatible with automatic transmission Datsun 510s?

Yes, the kit fits both manual and automatic transmission models. The exhaust routing is the same for both. However, if your car has an automatic, you may have additional linkage or cooler lines near the transmission tunnel; double-check clearance when positioning the mid-pipe.

Conclusion

Upgrading the exhaust system of a Datsun 510 with a Midas Performance Kit is a worthwhile investment for any enthusiast looking to boost performance. With the potential for 15 horsepower gains, improved sound, and ease of installation, this upgrade is sure to enhance both the driving experience and the vehicle's overall performance. By following the steps outlined above and taking the time to tune the engine afterward, you can transform your vintage Datsun into a more responsive and thrilling machine. Whether you’re a weekend cruiser or a track-day regular, the Midas kit delivers a noticeable upgrade that honors the 510’s legacy as a nimble, tunable sport sedan.

For more information about the Midas Performance Kit, visit Midas's official website. You can also find community support and installation tips on the Datsun 510 Forum. For general exhaust tuning fundamentals, check out this Hot Rod article on exhaust backpressure myths.