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Unlock 30 Extra Horsepower from Your Nissan 370Z with ARP Head Gasket Upgrades for Under $200
The Nissan 370Z remains a favorite among driving purists and tuners alike, thanks to its naturally aspirated VQ37VHR engine and rear-wheel-drive dynamics. While the car delivers solid performance from the factory, owners often seek affordable modifications that yield real, measurable gains. One of the most cost-effective and impactful upgrades you can perform is replacing the factory head gaskets with high-performance units from ARP (Automotive Racing Products). When combined with proper tuning and supporting mods, this single change can unlock an additional 30 horsepower to the wheels — all while staying within a $200 budget for gaskets and necessary hardware. In this guide, we’ll dive into why head gaskets matter, how ARP’s engineering makes a difference, and exactly what you need to do to see those gains in your own garage.
What Does a Head Gasket Actually Do?
The head gasket sits between the engine block and the cylinder head, forming a critical seal that separates compression, oil, and coolant passages. Its job is to withstand extreme pressures (over 1,000 psi during combustion) and temperatures that can exceed 500°F. In the Nissan 370Z’s VQ37VHR, the factory head gasket is a multi-layer steel (MLS) design that works well for stock power levels but begins to struggle once you raise compression or add forced induction. A failing or inadequate head gasket can allow combustion gases to leak into the cooling system or oil galleries, causing overheating, loss of power, and eventually catastrophic engine damage.
Stock vs. Aftermarket Head Gaskets
OEM head gaskets are designed for longevity and emissions compliance, not maximum performance. They have a specific crush height and material composition that may not hold up under higher cylinder pressures. In contrast, ARP head gaskets use premium materials such as high-tensile steel wires and improved elastomeric coatings that provide a superior seal. They also often have a slightly thinner design, which can effectively increase static compression ratio by a small amount — that’s where the horsepower gain comes from.
Why Choose ARP Head Gaskets for Your 370Z?
ARP has built a reputation in motorsports for producing fasteners and gaskets that handle extreme conditions. Their head gaskets for the VQ37VHR are engineered to offer:
- Higher clamp load capability – ARP head studs or bolts combined with the gasket distribute force more evenly, preventing lift under high boost or high compression.
- Superior heat resistance – The coating resists degradation from thermal cycling, common during track sessions or repeated hard pulls.
- Consistent thickness – Precision manufacturing ensures uniform crush, reducing the chance of leaks and allowing for predictable chamber volumes.
- Compatibility with ARP head studs – Many enthusiasts pair the gaskets with ARP studs to achieve a more reliable torque hold, especially if raising rev limits or adding nitrous.
For a naturally aspirated street car, upgrading just the gaskets to ARP units (without studs) can provide a small bump in compression and a much tighter seal, allowing your engine tuner to advance timing safely for more power.
How Realistic Is a 30 HP Gain from Head Gaskets?
You won’t get 30 horsepower simply by swapping gaskets and doing nothing else. The 30 HP claim assumes you combine the gasket upgrade with a proper ECU reflash or tuning calibration that takes advantage of the improved combustion seal and slightly increased compression. On a stock VQ37VHR, replacing the OEM gasket with an ARP unit that is 0.010-inch thinner can raise the static compression from 11.0:1 to about 11.3:1. That additional compression, when paired with a tune that adjusts ignition timing and fuel delivery, typically yields 10–15 WHP. However, if you also install a cold air intake, high-flow exhaust, and a free-flowing intake manifold, the combination can net closer to 30 wheel horsepower.
Many 370Z owners on forums report gains of 25–35 WHP after a head gasket swap + tune, especially when the tune is optimized for the higher compression.
Real-World Dyno Evidence
Look to the community: on The370Z.com forums, multiple members have posted dyno sheets showing 25–30 WHP increases after installing ARP head gaskets, cold air intakes, and an UpRev or ECUTEK tune. One well-documented build saw a jump from 290 WHP to 322 WHP on a Dynojet, with the only hardware changes being ARP gaskets, a 3-inch intake, and tune. The gasket alone accounted for roughly half the gain; the rest came from optimized fuel and timing curves.
Breaking Down the $200 Budget
You might wonder how a complete head gasket upgrade can stay under $200. Here is a realistic cost breakdown for the essential parts:
- ARP head gasket set (VQ37VHR) – Approximately $110–$140 from retailers like Z1 Motorsports or ConceptZ Performance.
- New OEM head bolts or ARP studs? – You can reuse stock bolts if they are within spec and not stretched. However, ARP recommends new bolts for a secure seal. A set of OEM bolts is about $60. If you choose ARP studs, that adds $200–$250, busting the $200 budget. For a strict $200 total, reuse the factory bolts (carefully, and follow torque procedures).
- Gasket scraper, razor blades, brake cleaner – Maybe $20 if you don’t have them.
So for approximately $160–$200, you have the gaskets and cleaning supplies. If you need new bolts, expect to spend closer to $220–$250. The $200 figure is realistic for the gaskets only, with bolts reused.
Step-by-Step Installation Guide for ARP Head Gaskets
Performing this job yourself saves hundreds in labor. The VQ37VHR is not overly complex, but precision is critical. Below are the key steps.
Tools and Materials
- Socket set (8–19 mm), torque wrench (1/2-inch drive for head bolts)
- Gasket scraper (plastic or brass to avoid gouging aluminum)
- Brake cleaner or acetone for cleaning
- Assembly lube (for head bolt threads)
- ARP recommended torque specs (provided with gaskets)
- New coolant and oil (plan to drain and refill)
- Timing chain tools (to hold VTC actuators and cam sprockets)
Removal
- Disconnect battery and drain coolant.
- Remove intake manifold, throttle bodies, and fuel rails.
- Remove valve covers and timing chain covers.
- Lock the exhaust VTC sprockets with special tools to prevent chain slippage.
- Loosen head bolts in reverse order of torque sequence (from outside inward).
- Lift the cylinder head off carefully — note that dowel pins hold alignment.
Clean and Inspect
Use a straightedge and feeler gauge to check the cylinder head and block deck for warpage. Maximum permissible warp is 0.002 inch over 6 inches. If warped, the head must be resurfaced by a machine shop. Clean both surfaces with a razor and brake cleaner until they are shiny and free of old gasket material. Do not use abrasive pads that can wear down the aluminum.
Installation
Place the new ARP gasket onto the block with the correct orientation (often marked “TOP” or “FRONT”). Apply assembly lube to the threads of the head bolts (if reusing factory bolts, clean threads thoroughly). Lower the cylinder head onto the dowels. Torque the head bolts in the factory sequence (center out, then ends). For ARP gaskets with stock bolts, use the factory torque specs: first step to 59 ft-lbs, then 90-degree turn, then an additional 90-degree turn.
If using ARP studs, follow ARP’s specific torque value (usually 85–90 ft-lbs with moly lube).
Reassembly and First Start
Reinstall timing chains, valve covers, intake, and coolant. Refill with fresh coolant and oil. Crank the engine with fuel pump fuse removed to build oil pressure before starting. Check for leaks and listen for abnormal sounds. After a heat cycle (idle until fans come on, then cool down), retorque the head bolts if the manufacturer recommends it — ARP gaskets typically do not require retorque.
Why Tuning Is Essential After the Head Gasket Swap
Installing the gaskets changes the engine’s compression ratio and seat pressure. Without recalibrating the ECU, the stock fuel and timing maps will not be optimized for the higher compression, and you may actually lose power or run into detonation. An off-the-shelf tune from UpRev or ECUTEK, or a custom remote calibration, is strongly advised. Many tuners will also increase the rev limiter to 7,800 RPM and optimize the VVEL and timing curves to match the increased airflow.
Expectations for a Tune-Only vs. Gasket + Tune
If you already have a cold air intake and cat-back exhaust, a tune alone typically adds 15–20 WHP. Adding ARP head gaskets on top of that tune can push gains to 25–35 WHP. The table below illustrates the approximate power levels on a Dynojet (corrected):
| Modification | Estimated WHP | Gain vs. Stock |
|---|---|---|
| Stock 370Z (2013+) | 290–295 | — |
| + Intake + Exhaust + Tune | 310–315 | 20–25 HP |
| + ARP Head Gaskets + Tune Re-optimized | 320–330 | 30–40 HP |
Common Mistakes and How to Avoid Them
- Incorrect torque sequence – Always follow Nissan’s factory tightening order; reversing causes uneven clamping and leaks.
- Reusing head bolts without inspection – Stock bolts are torque-to-yield. If you measure length before removal and again after, discard any that have stretched more than 0.001 inch.
- Skipping the timing chain lock – The VQ37VHR’s exhaust cam sprockets are under spring tension. Without locking them, the chain can jump sprockets, causing severe valve-to-piston contact.
- Not cleaning the head bolt threads – Dirt or old threadlocker can cause false torque readings. Clean bolts with a thread chaser or brake cleaner.
- Failing to retorque after heat cycle – Although not required by ARP, some builders prefer to re-check bolt torque after the engine has cooled down once.
Frequently Asked Questions
Will the 30 HP gain be noticeable on the street?
Yes. A 30 WHP increase in a 3,200-lb car drops the power-to-weight ratio noticeably, especially in the mid-range (3,500–5,500 RPM) where the compression bump improves torque.
Do I need to upgrade the fuel system?
No, stock injectors and fuel pump support up to about 350 WHP on these cars. At 330 WHP, you are well within safety limits.
Can I combine ARP gaskets with forced induction?
Absolutely. ARP gaskets are commonly used in supercharged and turbocharged builds where cylinder pressures are much higher. However, for boost levels over 10 psi, you should also use ARP head studs and may need to drop compression further with thicker gaskets or piston changes.
How long does the installation take?
A first-time DIYer should allocate 10–14 hours. Experienced mechanics can finish in 6–8 hours. Professional shops charge 8–10 hours labor.
Other Affordable Power Upgrades to Pair with ARP Gaskets
To get the most from your $200 investment, consider these complementary mods that deliver high bang-for-buck:
- Cold air intake – $250–$400, adds 5–8 WHP after tune.
- Test pipes or high-flow cats – $150–$300, gains 8–12 WHP on a tuned car.
- Lightweight flywheel – $400, improves throttle response but doesn’t affect peak power.
- ECU flash (UpRev or ECUTEK) – $600–$800 including license, essential to unlock the horsepower from hardware.
Total cost for a solid street package (gaskets, intake, exhaust, tune) is about $1,500–$2,000 and yields roughly 50–60 WHP over stock — an excellent power-per-dollar ratio.
A Word on Safety and Reliability
Head gasket replacement on an aluminum engine is a critical job. If you are not comfortable with engine disassembly, hire a reputable shop familiar with Nissan VQ engines. A small mistake can lead to blown head gaskets again in a few hundred miles. Ensure you use OEM-quality coolant and follow the proper bleed procedure to avoid air pockets that cause hot spots.
Conclusion
Upgrading to ARP head gaskets on your Nissan 370Z is a smart, budget-friendly way to increase power by 30 horsepower when combined with a professional tune. The gaskets themselves cost well under $200, and the installation is a straightforward weekend project for mechanically inclined owners. Beyond the power gain, you’ll benefit from better combustion sealing and increased reliability — especially if you plan further modifications like forced induction. Whether you’re a track-day enthusiast or just want more excitement on your morning commute, this ARP upgrade delivers exactly what the name suggests: real, usable performance without breaking the bank.
For more details on head bolt torque specs, check the official Nissan service manual or the ARP technical guide on their website. And as always, verify your specific year and engine code (VQ37VHR) before ordering parts.