The Guide to Nissan 370z Headers. The Nissan VQ37VHR V6 engine found within the Nissan 370z coupe is a superb and competent machine. It is naturally aspirated and produces 325-350 horsepower and 276 pound-feet of torque from the factory, depending on market and trim. The 370z, like its predecessor the 350z, is suitable for engine upgrades and alterations that improve horsepower and torque. Headers are a popular addition for the VQ37VHR since they increase power and improve the exhaust tone. This post will examine at the best header improvements for the 370z, as well as the benefits, pricing, and other factors.
What exactly are 370z Headers?
Let’s start with an explanation of what exhaust headers are and how they work. Headers are the components of an automobile’s exhaust system that link directly to the engine. They are commonly referred to as exhaust manifolds in their factory form. The phrase headers usually refers to aftermarket equipment. Headers are made up of two major components: individual runners that link to each of the cylinders and a merge collector where they all come together to form one giant pipe.
Headers gather the hot gasses emitted by the engine and route them through the rest of the exhaust system. They bolt straight to the cylinder head(s), and because the 370z has two cylinder banks, two headers are used to make one set.
The OEM exhaust manifolds provide acceptable performance for stock power levels. Aftermarket headers, on the other hand, become incredibly beneficial for anyone trying to enhance horsepower and get the most out of their other bolt-ons.
Aftermarket exhaust headers are designed to increase the velocity of exhaust gases leaving the engine. The faster oxygen-depleted exhaust gases exit the engine, the faster oxygen-rich clean air can replace them. This translates to higher horsepower and torque. To enhance exhaust velocity, minimize back pressure in the exhaust system, which is (typically) accomplished by employing larger diameter runners and a larger merge collector than stock.
How Do 370z Headers Function?
You might believe that because the purpose is to lessen back pressure, you can simply slap on the largest exhaust headers available to create the most power. That, however, is incorrect. We’ll try not to get too technical here, but you should have headers that are designed to take full use of air pressure waves. Taking advantage of pressure waves provides for the best scavenging effect possible, as we’ll discuss below.
First, keep two exhaust principles in mind: one, air will always seek to travel from high pressure locations to low pressure places. Second, the pressure within an engine is substantially higher than the air pressure. This indicates that air wants to depart an engine and pass through your exhaust.
Returning to pressure waves. When your engine’s exhaust fumes enter the headers, they form a positive pressure wave that moves outward. When a positive high pressure wave strikes the merging collector, it emits a negative low pressure wave that travels all the way to the cylinder. If the header is properly built, the negative pressure wave will arrive at the cylinder’s exhaust valve exactly as the last exhaust gasses are being emitted.
The negative low pressure wave will aid in the removal of the remaining spent exhaust gas while also drawing new clean air into the intake. This is due to the fact that, as previously said, air goes from high to low pressure. This entire process is known as scavenging, and it benefits the engine.
Why are proper headers necessary?
correct headers are critical since your engine may experience exhaust gas reversion if correct scavenging and back pressure reduction are not implemented. Reversion is the inverse of scavenging and occurs when there is excessive back pressure. The pressure differential between the exhaust and the engine is reduced by back pressure. This causes exhaust air to stay inside the engine and exhaust, preventing the engine from receiving new and clean air.
Furthermore, the inertial scavenging effect decreases as the exhaust vapors move slower. Though we did not mention it previously, inertial scavenging is critical. Inertial scavenging occurs when positive pressure waves pass through the exhaust and away from the engine, leaving a low-pressure area behind. Because air flows from high to low pressure locations, it draws more gas into the engine more quickly.
The higher the velocity of the exhaust, the lower the pressure region in its trail, therefore the faster the exhaust, the lower the pressure, and the faster it will eventually suck out more exhaust fumes. As previously stated, the faster this process occurs, the more horsepower and torque the engine produces. Importantly, adequate piping and merging collector sizing and design is critical for maximum velocity. Piping that is too tiny or too large reduces velocity, therefore precise measuring is essential.
This is why it’s critical to only acquire headers from suppliers who take the time to work on your design. No matter what assurances the manufacturer makes, if your headers do not lower back pressure, increase scavenging and inertial scavenging, and reduce reversion, you will be worse off than before.
Long-tube vs. Short-tube Nissan Z34 Headers
Long-tube headers and short-tube headers are the two most frequent types of aftermarket 370z headers for the VQ37VHR. The fundamental distinction between the two is, as their names suggest, their length. Short-tube headers are solely intended to replace the exhaust manifold up to the catalytic converters. Long-tube headers, on the other hand, reach much further back, all the way to where the cat-back begins.
Long-tube headers will outperform short-tube headers in terms of total performance advantages. The reason for this is that long-tube headers remove or replace the system’s catalytic converters. Catalytic converters are significant exhaust limits that cause a lot of back pressure. Removing or replacing them reduces back pressure, encouraging scavenging and exhaust flow.
However, there are major legal concerns to consider while removing your cats, which we’ll discuss further below.
High-flow Cat Headers vs. Catless Headers
The distinction between long-tube and short-tube 370z headers, as previously stated, is that long-tube headers frequently remove the catalytic converters entirely. Unfortunately, this means that long-tube headers may violate local emissions rules in some areas. Removing catalytic converters from your exhaust is a violation of federal and most (but not all) state emissions laws.
To get past the prohibition on removing catalytic converters, several manufacturers would use high-flow catalytic converters instead of removing them entirely. Because they contain a catalytic converter, these headers are normally emission-compliant. However, because the converters are not as strong as stock, they still result in lower back pressure. This is a decent halfway point for most individuals because it provides for greater performance while still remaining legal on the road.
Short-tube headers keep the 370z’s standard catalytic converters and are the ideal alternative for individuals who don’t want to touch any emissions equipment. It’s worth noting that in some jurisdictions, even high-flow catalytic converters are deemed non-compliant for emissions, leaving short-tubes as the sole legal choice.
Some manufacturers make test pipes for customers who only want to remove the catalytic converters from their exhaust while keeping the bulk of the stock unit in place. The catalytic converter component of the exhaust manifold is only replaced with these, leaving the rest of it untouched.
Technically, test pipes can be added to short-tubes, but at that point, you should probably just get a full set of long-tubes. Test pipes are useful for replacing the most restrictive section of the exhaust system, and their performance increases fall somewhere between long and short tubes.
The Advantages of 370z Header Upgrades
We’ve gone over some general information on header upgrades; now let’s get specific to the 370z VQ37VHR headers. Most enthusiasts considering 370z header improvements are interested in power gains, but there are several other advantages as well. Some of the advantages of 370z header upgrades include:
- +10-30% increase in horsepower
- +5 to 20 lb-ft torque
- Back pressure has been reduced.
- increased scavenging of exhaust
- Exhaust sound has been amplified.
A set of 370z headers will add 10-20 horsepower and 5-15 lb-ft of torque on their own. With tweaking, you should expect to see an increase of 15-30 horsepower and 10-20 lb-ft of torque. But we’ll get into that more later. In addition to greater horsepower and torque, one of the most significant benefits of header upgrades is lower back pressure and increased scavenging efficacy, as previously discussed.
The change in exhaust volume and tone caused by the larger diameter pipes is another hallmark of 370z header upgrades. Aftermarket headers will significantly boost the volume of one’s exhaust while also producing a raspier and more aggressive tone. Both effects are exacerbated more by long-tube headers than by short-tube headers. The difference is most noticeable at full power and on cold starts, but it is also noticeable at idle.
HP Gains for Nissan 370z Headers
Now, let’s return to the most significant aspect of VQ37BHR header upgrades: power increases. As previously stated, without a tune, upgraded 370z headers will often produce improvements of 10-20 horsepower and 5-15 lb-ft of torque. Gains from a tune typically rise by 5-10 horsepower and 5-10 lb-ft of torque. Because headers dramatically modify exhaust flow characteristics, ECU tuning is highly recommended for any header upgrades. Without tune, improved headers can create lean air-to-fuel ratios at WOT, resulting in detonation and pre-ignition, which can lead to catastrophic engine failure.
Again, 370z long-tube headers often produce greater power across the rpm range than 370z short-tube headers. This is due to the fact that 370z short-tube headers still use the restricted original catalytic converters. Short-tube headers will still provide a notable power boost over standard, but it will pale in comparison to what long-tube headers will provide. Other modifications, such as intakes and cat back exhausts, will also aid to boost overall air and exhaust flow.
Headers are an excellent way to increase power and loudness without adding forced induction. When combined with the aforementioned changes like as intakes and cat backs, enthusiasts can truly tune their exhaust note to their preferences by experimenting with all of the potential combinations.
Best Nissan 370z Header Modifications
Now that we understand what headers are and why they are crucial for the 370z, let’s look at some recommendations. Because there are so many options, this list is not intended to be thorough or comprehensive. Rather, this list is intended to be a look at the best practical 370z headers on the market today. The list includes both 370z long-tube and short-tube headers to accommodate a wide range of budgets, setups, and power goals. In no particular order, here are the top-five header improvements for the 370z’s VQ37VHR.
- Long-tube Fast Intentions 370z Headers
- Long-tube Headers for the Motordyne 370z
- Long-tube PPE Engineering 370z Headers
- Short-tube Headers for the 370Z by Z1 Motorsports
- Short-tube DC Sports 370z Headers
- Shorty & Long-tube Headers – VQ37VHR Shorty Headers
- Short-tube Headers from Z1 Motorsports
1) 370z Long-Tube Fast Intentions Headers
Price: $1,359.00 – $1,899.00
All years are compatible.
The Fast Intentions 370z Long-Tube Headers are the first item on the list. There are two versions, one for 2009-2011 models and another for 2012-2021 models: both are catless. They are also available in two finishes: non-polished stainless steel and black ceramic. The black ceramic can endure temperatures of up to 1,600°F, but it comes at a $450 premium. According to the manufacturer, the header was especially designed to be firing order specific in order to ensure optimum scavenging and reduce turbulence.
When combined with a high-flow cat back exhaust, they witnessed average improvements of 8 wheel horsepower and a maximum of 15 wheel horsepower and 18 wheel torque, according to their website. The product is handcrafted and produced to order, and it is Fast Intentions’ loudest alternative.
With the ceramic coating, they can be a little pricy, but they are still a decent deal and a viable option for a 370z long-tube header modification. The sound and performance advantages are praised in the reviews for the FI headers.
2) Long-Tube Motordyne 370z Headers
Price: $2,077.95 – $3,269.95
All years are compatible.
Motordyne comes in second, and they are by far the most expensive option on the VQ37VHR. Motordyne is a newcomer to the 370z scene, but their products already have a great reputation. Among 370z headers, the Motordyne 370z Long-Tube Headers are unusual. It is the only dependable long-tube header option that is compatible with high-flow catalytic converters. Users can select from a straight-pipe, helmholtz resonator, or high-flow cat configuration. They can be modified without removing the entire header. This is extremely handy for individuals who require cars that are both street-legal and track-ready.
Motordyne’s long-tube headers, according to their website, may produce improvements of up to 25 wheel horsepower and 10 wheel torque with ECU tweaking. They are a little difficult to find because they are only prepared in small batches and are frequently out of stock. However, when they are available, they are a top-tier alternative. The cost can be a deterrent, but the interchangeability is great. Motordyne’s 370z headers have received favorable feedback, with users praising the exhaust tone, performance, and fitting.
3) PPE Engineering 370z Long-tube Race Headers
All years are compatible.
The PPE Engineering 370z Long-Tube, Equal-length Race Headers are next on the list. PPE Engineering is a well-known Nissan performance company, and their headers have received rave reviews from those who have utilized them. They are widely recommended by owners for their forceful tone and performance benefits, although they, like the Motordynes, can be difficult to find. They are all created to order and must be acquired from a dealer rather than directly from the manufacturer.
According to the manufacturer’s website, their VQ37VHR long-tube race headers produced improvements of up to 23 wheel horsepower. They say that with a tune, their headers can produce an astounding 35 wheel-horsepower. These, like the FI headers, have a ceramic coating. They’re a great option for a header improvement and a good compromise between the FI and the Motordyne.
4) Headers 370z Z1 Motorsports Performance
Price: $1,399.00 – $2,197.00
All years are compatible.
The Z1 Motorsports Short-Tube Performance Headers are the first pair of short tube headers on our list. These were initially intended for the 350z, but they can also be used on the 370z with the standard catalytic converters, high flow cats, or test pipes (as specified by the manufacturer). Buyers of the 370z will also require new gaskets to connect the manifold to the cats. Buyers praise the Z1s for their exceptional construction, excellent fit, and decent performance benefits.
The Z1s will not provide the performance of the first three headers on the list due to their short tube length, but they will be useful and aid in power while remaining entirely emissions compliant. The merging collector is sturdy, and the runners are of identical length to aid with scavenging. Overall, they are ideal choices for individuals who want to keep their stock cats.
5) DC Sports 370z Polished Header
All years are compatible.
The DC Sports Short-Tube Headers are the final item on our list. The DC headers are by far the most affordable choice on the market, yet they still provide some good improvements. They have equal-length runners, can be ordered with ceramic coating, and are a direct OEM bolt-on installation.
For those wishing to upgrade their 370z on a budget, the DC headers are a nice option. They won’t provide the same performance advantages as long-tube headers, but their greater diameter will improve exhaust flow and free up some extra horsepower.
Summary of Nissan 370z Headers Upgrade
Headers are a vital modification for 370z owners who want to get the most out of their vehicle. They will not only increase power throughout the rpm range, but the reduced back-pressure will improve scavenging, lessen reversion, and can lower exhaust gas temperature – all of which are crucial aspects. Your exhaust tone will also become raspier and more forceful, mirroring the VQ37VHR engine’s particular traits.
Header improvements can produce 10-35 wheel horsepower and 5-20 wheel torque, depending on size, manufacturer, and whether or not tuning is used. Tuning provides the biggest bang for the money and should be utilized in combination with any 370z header improvement. Long-tubes can add up to twice the horsepower of short-tubes. However, with the exception of the Motordyne’s high-flow cat option, they also violate emissions laws.
These headers are all excellent prospective improvements for the 370z. The FI headers are the most cost-effective long-tubes, with solid increases. The Motordynes are by far the most expensive, but they are also the most distinctive, with the option to switch between catless and high-flow cats. PPE Engineering headers are the industry standard for many long-tube applications, although they are not always easy to locate and are significantly more expensive than FIs. Both short-tube headers are good modifications for those wishing to keep emissions compliant, with budget installations favoring the DC headers due to their lower cost.