Best Nissan Altima Mods - Altima 2.5 & 3.5 Engine Performance Upgrades

The 6 Best Nissan Altima Mods & Upgrades

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The Nissan Altima and Altima Coupe may not be the fastest cars around. However, they can be great project cars to upgrade and modify. Modded Nissan Altimas with the 2.5 and 3.5 can offer good performance in a reliable and affordable package. That is a good combo for anyone, but it’s especially true for people newer to the aftermarket mods scene.

When it comes to performance the biggest improvements are going to come from tuning, intakes, exhaust upgrades, headers, pulleys, and turbo kits. We’re going to discuss each of these in-depth below, covering benefits, power gains, and more.

Best Nissan Altima Mods - Altima 2.5 & 3.5 Engine Performance Upgrades

Best Nissan Altima Performance Upgrades

  • Tune
  • Intake
  • Exhaust
  • Headers
  • Pulleys
  • Turbo Kit

These modifications are going to be most applicable to the QR25DE and VQ35DE engines. While they are also applicable to all others that the Altimate uses these two are going to be the best for performance and therefore will see the biggest power gains from these mods. With respect to these two, the 3.5L engine will offer bigger gains due to the larger displacement.

1) Nissan Altima Tuning

Tunes are often easy to purchase & install, and can offer solid power gains for the price. Unfortunately, that isn’t the case for the Altima 2.5 or 3.5 engines. Off-the-shelf tuning options don’t really exist for these engines. That doesn’t mean they can’t be tuned, but it’s usually not the first mod we would recommend.

With simple mods like an intake and exhaust a tune isn’t going to add much power or performance. You’ll maybe pick up an extra 3-7 horsepower. Some may see the value in tuning the Nissan Altima even with these basic mods. However, we don’t think it’s necessarily worth the cost or hassle.

However, start adding more mods like headers, throttle bodies, cams, etc. and tuning becomes a lot more valuable. In these cases you may see gains in the 10-20 horsepower ballpark from just the tune. Point is – Altima tunes can be a great mod, but it’s usually best to knock out the other upgrades first.

2) Cold Air Intake Upgrades

An intake is a standard upgrade that most car enthusiasts are into. It’s hard to find a modded Altima (or almost any other modded car) that doesn’t have an intake upgrade. Why? These are cheap, simple mods that offer fair results for the price.

You may also hear intakes referred to as filters, cold air intakes, performance intakes, or intake systems. The last three are often used interchangeably. There is a difference when discussing just intake filters, though. We’ll discuss that in a few moments.

Performance benefits of intakes include:

  • 3-10 horsepower gains
  • Similar torque gains
  • Better throttle response
  • Improved sounds

A modified Nissan Altima intake can offer gains of about 3-10 horsepower. Without other mods expect results on the lower end. You’ll also pick up pretty similar torque gains. The power/torque gains are also throughout most of the rev range, so it adds a decent bit to the overall power band.

Many notice better throttle response with Altima intake mods. This is especially true if you opt for an intake with straighter piping. Stock Nissan Altima intakes bend quite, which can slow the flow of air into the engine. It’s also a large reason the intake upgrades offer solid power gains. You probably won’t notice a huge change in sound, but intakes can help wake things up a little bit.

3) Exhaust Mods

Next up on the list of best Altima mods is an exhaust system. As with the intake the 2.5 & 3.5 exhaust doesn’t flow very well. A lot is also due to bends. It doesn’t allow for a straight, efficient path for exhaust gas flow. There are tons of different options with Altima exhaust upgrades and we don’t have time to cover it all.

Options include cat-backs, axle-backs, y-pipes, full exhaust systems, etc. The more exhaust you replace the better power gains you’ll see. Going with catless systems also offer the best performance and bang for your buck. However, they’re intended for off-road use only.

Benefits of Nissan Altima 2.5L and 3.5L exhaust upgrades include:

  • 5-10 horsepower
  • Similar torque
  • Engine/exhaust sounds

For basic mods alone a 5whp gain may be an aggressive number. However, a good free flowing exhaust can offer solid power gains with additional mods like tuning, intake, headers, and more.

Ultimately, an exhaust can be a great mod for the Altima. It wouldn’t really be at the top of our list since you can get better power gains relative to the price point. Many exhaust systems are going to run about $500-1,000. We think exhaust upgrades are best for those who want sound and some power on the side. If your only goal is power then the money is better spent on other mods.

Nissan Altima Headers Exhaust Manifold Upgrades

4) Headers

Are you looking for the absolute best bang for your buck Nissan Altima mods? If so, headers are the near the top of the list. Headers are also commonly known as the exhaust manifold. Headers bolt directly to the cylinders exhaust ports. It’s the most important part of the Altima’s exhaust system due to its location.

The idea of exhaust mods is to reduce back-pressure. The closer to the engine the back-pressure is reduced the bigger the power gains.

Benefits of Altima header mods include:

  • 8-15 horsepower
  • Similar torque
  • Sounds
  • Lower EGT / Healthy for engine

Considering most headers run around $100-300 it’s hard to beat these power gains. However, DIY’ing exhaust manifolds are more challenging than most of the other Nissan Altima mods on this list. You really just won’t find another mod that offers this much power for the price point, though.

Sounds are another benefit, and most headers aren’t obnoxiously loud if the rest of the exhaust is stock. Reducing back-pressure also helps lower temperatures, and is healthy for the engine overall.

5) Pulley Upgrades

We’ll be a little quicker moving through these next sections. The drive belt connects to a pulley, which weighs in around 4-5 lbs on the stock Altima 2.5 and 3.5 engines. Changing this pulley to a light-weight option can help reduce rotational mass. In essence, it makes it easier for the engine to drive the belt and pulley.

Power gains with Nissan Altima pulley mods aren’t huge, but it’s a pretty inexpensive upgrade. Expect the following hp and tq gains with a pulley upgrade:

  • 3-7 horsepower
  • 3-7 torque

It might not be too appealing. However, horsepower gains aren’t always easy to come by on NA engines. Check out 2J-Racing as they have some popular options for the QR25 Altima 2.5 engine. Stillen also has some options for the 2.5 and 3.5 engines.

6) Nissan Altima Mods – Turbo Kit

Turbo kits aren’t a topic we’re going to cover in-depth in this article. It’s a long topic that would need a lengthy article just to scratch the surface. The main reason we’re adding a turbo kit here is to discuss bigger power mods.

Naturally aspirated (NA) engines like the 2.5L and 3.5L Altima engines don’t have tons of modding capability. Once you reach the limits with NA mods it’s time to consider turbo or supercharger kits and other more serious, expensive mods.

It also brings about higher risk of engine damage and problems while running boost. Adding forced induction isn’t for the faint of heart. However, the QR25 and VQ35 hold up pretty well on moderate boost. It’s a good option if you’re looking to pick up more than 50whp.

By the time it’s all said and done you could easily spend $5,000+ just for engine mods. Then you need to consider suspension, wheels & tires, and other mods to handle the newfound power. Point is – the gains from turbo kits or the like might be appealing, but costs can spiral out of control.

Mods by Power Goal

When combining certain Nissan Altima mods how much power can you expect? How much power can a fully modified Altima make? There isn’t a perfect answer since results can vary a lot from car to car. However, let’s jump into some general numbers and the best Altima mods to hit specific goals.

Altima Mods For 10-20whp Gains (~$1,000)

  • Intake
  • Pulley
  • Tune

These mods can be done for around $1,000 if not a bit less. An Altima with an intake, pulley, and tune should pick up at least 10whp. Gains may even be a bit higher, especially on the 3.5L VQ35DE Altima engine. You can also substitute certain mods here, such as opting for an exhaust instead of a tune.

If you plan to do headers or other more serious mods in the future then holding off on the tune is a good idea. To maximize output you’ll end up re-tuning the car after headers, which can add an unnecessary expense. However, a tune is a good option here if you’re planning on stopping after a couple basic mods.

Upgrades For 20-30whp Gains (~$1,500)

  • Intake
  • Pulley
  • Headers
  • Tune

Modded Altimas with the above upgrades should see total gains of around 20-30whp. It may be a little lower on the QR25 engine or maybe a bit more power on the Altima 3.5 V6. Anyways, it’s pretty much the same list as above with the addition of headers. These alone can help pick up the extra 10-15+whp.

None of this is a perfect science, so you can add or remove mods from the list as you see fit. However, a tune is definitely a good mod to have once headers are installed. Still wanting more power? Time to add a couple more mods.

30-40+whp Gains ($2,000+)

  • Intake
  • Pulley
  • Headers
  • Tune
  • Exhaust
  • Throttle body
  • Cams (optional for more power)
  • Forced induction (optional for more power)

The first 6 mods on this list is pretty close to all of the basic bolt-on mods for the Nissan Altima. With all of these mods you might see gains close to 30-40whp. Again, it might be a stretch for the smaller 2.5L inline-4 engine. Going much further on either engine is starting to get into expensive territory. You’ll be looking at more serious mods like cams, turbo or supercharger kits, etc.

+40whp Is About It Before Turbocharging

When it comes to mods and upgrades the Nissan Altima isn’t the first car that comes to most peoples minds. However, they can be great cars that are fun and easy to modify. The Altima 3.5 even uses the VQ35DE engine found in Nissan 350Z models. It’s the best 2002-2018 Altima engine when it comes to performance potential.

A couple basic bolt-on Nissan Altima mods can help unleash about 10-30whp depending on how far you go. A tune, intake, exhaust, headers, and pulleys are all good starting points. Those looking for more should consider more serious mods like forced induction, camshafts, and other options.

Anyways, the Nissan Altima is pretty easy to modify and they remain reliable engines with basic mods. Choose the mods that best meet your goals and budget. Otherwise, just have some fun with it and enjoy your newly modded Altima.

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    1. Hi Vermiss,

      Each to their own. There are definitely much better cars and platforms for engine mods and power gains. We would mostly agree when it comes to the QR25. However, the VQ35 is a solid engine that responds pretty well to mods for being an NA engine. If something more mod friendly is in the budget then it may be worth it. These are some good mods for those who just want a bit more out of their Altima or don’t have the option to change cars.


    2. Not a waist of money I did some research if you know how to install yourself most of the parts are fairly reasonable even if you get name brand

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