Find The Best Mods For Your Car!

Car Search

Lexus IS300h Tuning Guide & Best Mods

We are affiliated with the eBay Partner Network affiliate program and may make a commission when you purchase products through links on this page.

Table of Contents


Created by the luxury vehicle division of Japan’s renowned car manufacturer, Toyota, the Lexus IS300h serves as an epitome of style, performance, and green technology.

The ‘h’ in its name signifies its hybrid DNA, combining a 2.5L 4 cylinder petrol engine with an electric motor joining together to produce around 220hp.

This smooth power output delivers brisk acceleration, and it’s e-CVT transmission ensures a smooth, gearless ride for everyday driving. 

If you own a IS300h and are wondering if there are ways to modify it, then you’re at the right place.

In this guide we’ll go over the best ways to improve the looks of the car as well as the performance.

It’s worth noting that due to it’s hybrid nature and naturally aspirated engine, there aren’t many options out there for increasing the power output. Instead, you can improve the performance through upgrading the handling and brakes.

On the exterior side of things, there are variety of striking and subtle modifications you can do to make it all the more eye catching.

Let’s get started!


As we mentioned in the introduction, you are limited when it comes to tuning the car for additional power. 

Increased performance doesn’t need to come in the form of increased straight line power however.

Coilovers are a great way to improve the handling performance of the car as well as the looks.

Let’s take a look at the performance benefits.

By replacing the factory suspension setup with coilovers, drivers can experience a better road-feel and dramatically increased grip due to the lowered centre of gravity and increased stiffness.

This leads to improved cornering abilities and more sportier handling.

Coilovers also reduce body roll, which means your Lexus IS300h will remain more level when going through tight bends or corners.

Of course, it isn’t always about performance. Many owners install coilovers as a visual upgrade.

As you may know, coilovers allow you to adjust the ride height.

The lower stance contributed by the adjustable ride height not only reduces the gap between the tire and the fender but also lends the car a more distinctive, aggressive appearance.

So what set of coilovers should you go for?

Generally speaking with coilovers you get what you pay for, however you may not need some of the more expensive sets that are more focused on high performance driving if you simply want to lower the ride height without compromising too much on comfort.

BC Racing do a great coilover set for the IS300h with damping adjustment allowing you to fine tune it to suit your needs.

There are also other options from manufacturers such as Tein and KW.

BC Racing Coilovers

Lexus IS300h

Tein Flex Z Coilovers

Lexus IS300h

Rear Spoiler

When people talk about adding a rear spoiler to a car, you may picture a large track styled wing. While those spoilers have their place, a more subtle option is more suited to the IS300h.

A spoiler subtly transforms the rear end of the car, adding a sporty underdone to it.

By augmenting the clean lines and smooth contours of the vehicle, a spoiler signals speed and power.

You have some different options at your disposal.

You can purchase rear spoiler extensions like the one at the bottom of this section that slots on over the tip of the rear boot lid.

If you are wanting to go for a seamless blend and OEM look then these types of spoilers are ideal.

You can also opt for a universal styled spoiler in a different style however these will likely require some fitting and trimming to the fitment correct.

Most spoilers can usually be fixed with adhesive, and either come painted or unpainted. The spoiler we linked above can also come painted to match the colour of your Lexus. You could also opt for it in a slightly different colour such as black to make it a bit more prominent and add some contrast.

Boot spoiler for the IS300h

Boot Spoiler

For the IS300h

Sideskirt Extensions

One of the prime visual benefits of sideskirt extensions is that they lend a more aggressive, sport-inspired look to your Lexus IS300h, complimenting the already prominent lines of the car.

Sideskirt extensions also reduce the visible gap between the Lexus’s undercarriage and the road, enhancing its ground effect and giving it a lower looking stance.

There are some options out there that are made bespoke for the IS300h.

You can also go for universal styled sideskirts that can sometimes be a little cheaper however will require custom trimming to get it to fit the length of the car nicely.

Ideally look for sideskirts that are made from material like ABS. The ones linked above made for this car are. ABS is more resistant than many other fibreglass alternatives that can crack easily. 

Most sideskirt extensions will come unpainted so if you want them paint-matched to the car to preserve an OEM look, you will need to budget for this unless you can do this yourself. 

Of course, many owners like to keep the standard black styling of the extensions to give the lines a bit more contrast.


For the IS300h

Front Splitter

We’ve spoke about enhancing the rear of the car with a spoiler and the side of the car with sideskirt extensions, but what about the front?

If you’re looking for a simple way to make the front end more sporty and aggressive, then an aftermarket front splitter is what you need.

Out of the 3 discussed, a front splitter will arguably provide the greatest aero benefits. While minimal with most front splitters, they can effectively manipulates air flow, creating additional downforce at the front of the car.

Of course, most people don’t put a front splitter on their IS300h for the performance benefits.

A front splitter dramatically changes the look of the front of the car, giving it a more aggressive and sporty aesthetic.

Similar to the sideskirt extensions, it also helps visually lower the car and give it a more aggressive stance.

If you are looking for a front splitter that specifically fits the IS300h, then check out the one at the bottom of this section.

This slick looking front splitter also comes with sideskirts so if you’re looking to do both then you can save money buying these together.

Made from lightweight ABS, this splitter is a great way to transform the front of the car without breaking the bank and comes with the pre-drilled holes and screws required for fitting.

Front Splitter & Sideskirts

For the IS300h

Painted Brake Calipers

This is a simple yet bold upgrade that can make a massive difference to the looks of the car.

When painted, the brake calipers can serve as a stunning accent by contrasting the wheels and bodywork.

Not only do they add to the car’s visual appeal but they can also provide an extra layer of protection against rust and corrosion.

There are various colours you can go for with the most popular being red, yellow and a shade of blue. 

You could also go for something like silver if you don’t want them to pop as much but want to keep it looking elegant and fresh.

One of the best things about this modification is that you don’t need much technical expertise and it’s something you can do at home on your driveway.

You’ll want the following tools:

  • High-temperature brake caliper paint
  • Brake cleaner
  • Masking tape
  • Various size paintbrushes
  • Wire brush
  • Safety goggles
  • Hydraulic jack and jack stands

Once the IS300h is jacked and secured, remove the wheels to reveal the brake calipers.

Use the wire brush to remove dirt, rust, and old paint from the calipers. Then, apply the brake cleaner to get rid of any leftover debris, making sure everything is completely clean and dry before proceeding.

Use masking tape to cover any parts of the brake system that should not be exposed to paint.

Use a small paintbrush to apply a thin, even coat of paint on the calipers. Wait for the previous coat to dry before applying another coat.

Remember that the key to a good finish is in the prep, so don’t rush it!

Red brake caliper paint

Gloss Red Brake Caliper Paint

Gloss Yellow Brake Caliper Paint

Wheel Upgrades

The wheels are one of the most striking elements of the exterior, and can make or break any car. The IS300h is no exception. 

While there are various factory options for this car that are great, you may be looking for something a little different or bold.

The standard wheel sizes that came on these cars from the factory ranged between 16 and 18 inches.

It may be that you simply want to upgrade to a larger sized OEM wheel to give the car a sportier look. 

While larger alloys can look better, they can sometimes reduce the comfort due to the sidewall being smaller. Keep this in mind if you are planning on making a jump from 17 to 19 inches if you drive the car on uneven or bumpy roads.

If you are wanting a set of aftermarket wheels, then this of course opens up your options substantially.

Sites like Wheelbase are a great way to see what wheels are available for your particular model that fit out of the box. It can be confusing at time trying to work out what aftermarket wheels fit so going to that site and entering your IS300h’s year and wheel size is a great way of seeing your options.

If you are looking to shop around for wheels manually, ensure you have the correct bolt pattern, offset and centre bore in addition to the correct diameter.

In addition to swapping wheels, you can also look into adding wheel spacers.

Wheel spacers can provide a more aggressive look by pushing the wheels further out from the car’s body and give it a more streamlined stance.

Finishing Thoughts

We hope you enjoyed this guide on tuning and modding your IS300h.

Due to the hybrid and luxurious nature of the car, there isn’t a large aftermarket scene of parts.

But don’t let that discourage you!

This is a great opportunity for you to really make the car a head turner and something unique among the many out there that look the same.

Subtle modifications with this car tend to go a long way. A small rear spoiler, front splitter and some sideskirt extensions coupled with coilovers can radically alter the car’s visuals without being too over-the-top and tacky.

As mentioned at the start of this article, you are very limited with increasing the power so best to stick to a good set of coilovers and enjoy the handling benefits that they bring.

Happy modding!