Wednesday 21 August 2013

MX-5 Roadster NC Induction Options

Today I'm going to be taking a look at some of the aftermarket air intakes available for the NC Roadster. Some people will say not to bother fitting these and that the original intake system is perfect. Others will say the factory setup is restrictive and built to a compromise between cost, noise level, and performance. In my experience air intakes are one of the first things modified car enthusiasts look at changing.

Usually this is done in an unwavering quest for fresh cold air to reduce the temperature of the air entering the engine to squeeze out a few more horsepower. Others will choose to fit a new intake because they look impressive, produce a pleasing sound, or simply to satisfy a compulsive need to do something to their car. Fortunately the Roadster is well served by aftermarket companies and there is a good variety of intakes on offer.

First up is the intake from the accessory catalogue. It's the Mazdaspeed cold air intake, produced in conjunction with AEM. The intake consists of a long two-piece pipe that relocates the air filter behind the front grille in an optimum position for fresh air. Longer intake pipes are said to help with power gains, but if you are worried the position is too low and may suck up rain water, you can fit a special waterproof sock over the filter. The Mazdaspeed intake is part of the required spec in the MX-5 Cup race series.

Next we have the offerings from AutoExe, they have two setups available. The first is a replacement half of the factory airbox in their signature red colour. By removing the front piece of the factory box, airflow is increased to the filter. This setup comes with side brackets that help enclose the filter when the bonnet is closed. The second intake is a rebranded GruppeM Ram Air system. It consists of a large K&N cone filter enclosed in a carbon airbox and fed by an air scoop from the front grille.
The Beatrush intake is probably one of the most impressive looking. It uses an Apexi cone filter and encloses it in an gold aluminium box with a little folding lid. This intake reminds me of the gold Mazdaspeed airbox for the NA Roadster. This intake would be a great choice for those who like to show off, it probably makes a great sound too.
These next two intakes are near enough identical. The Fujita intake is similar to the Mazdaspeed AEM in that it takes the filter and positions it low down behind the front grille. This time though it is mounted on the opposite side using a slightly shorter and simpler design. The DC Sports intake uses the same parts as the Fujita with the exception of the generic filter and hose clips instead of Fujita branded parts.

Track Dog Racing have a high flow air intake that is a very no nonsense simple design. You can forget your fancy shiny pipes and golden airbox, this intake is a simple silicon pipe with a K&N cone on the end. It's positioned in a similar place to the factory setup.
As well as supplying air filters for countless applications, K&N also do a 57i branded kit for the Roadster. It's a simple elbow piece with a cone filter on the end. The filter remains in the engine bay so you also get a piece of hose to form a DIY cold air feed.
The HKS intake uses one of their traditional mushroom shaped sponge type filters. It is positioned just in front of the factory air intake hole using some shiny pipe bends and HKS branded silicon hose joiners. Nopro make a shroud that fits around the filter to help enclose it from engine bay ambient air and ensure it gets the most from the factory intake opening.
The GReddy intake is similar to the HKS in terms of positioning but is a much nicer piece. It has a GReddy branded unique intake pipe that gives a more professional look than the HKS kit which looks a bit cobbled together (to my eyes at least).
Not surprisingly, the Racing Beat intake looks great. It uses a well designed one piece pipe with a long thin cone filter and a ram air scoop. The filter is positioned in pretty much the same place as the factory intake pipe (the top part of the front bumper) and uses the wide scoop to bring in fresh air from the front grille opening. As with the Fujita and Mazdaspeed, it uses a long intake pipe.
The Moto-East intake is another fairly simple design, using a long straight intake pipe and positioning a cone filter in the upper part of the front bumper.
The award for the world's smallest induction kit goes to Wirus Win. Their kit is a tiny pipe adaptor that allows you to fit a cone filter onto the end of the factory intake elbow piece. Such a short intake probably makes a lot of noise, look at it as weight saving.
Not strictly offering a kit but getting an honourable mention is rotary specialist Odula. They have a high flow silicone intake elbow which is somehow better than the factory one, and also a nice looking and very understated air scoop for the factory airbox.
This intake by SCUD is a carbon fibre tube with an enclosed filter in a small cylindrical carbon airbox. It features a ram air type opening that would probably work best with a dedicated intake in the front bumper.
Do.Engineering have an intake for the Roadster, it's an enclosed filter that is fed directly from the factory air intake pipe.
Pipercross have an intake exclusive to MX5parts. It includes a replacement silicon intake elbow similar to the Nopro/Odula part, a complete replacement airbox made from carbon fibre, and a length of air duct hose to collect fresh air from behind the bumper.
Jet Steam have some intake options including this enlarged intake elbow available in carbon fibre, and an intake scoop for mounting in the front grille of the NC3 models.
Skuzzle Motorsport have created this setup for the NC known as the TorqIntake. It features carefully designed aluminium tubing paired with a RamAir cone filter.
So that was a quick look at some of the various induction options. Of course, if you don't want to go to the expense of fitting an induction kit, then there are performance panel filters you can use with the standard airbox from Cosworth, K&N, and Mazdaspeed.