Investment in Mods - Part One

There’s no two ways about it – a modified car is a money pit.

Don’t get us wrong. We’re not discouraging you from spending cash to pursue your interest and enjoy yourself, but don’t - DON’T - expect to get your money back when it comes time to sell. The sooner you accept this, the sooner you’ll start saving money; money you can waste on other things...

In this series we’ll show you ways to modify your car without blowing a wad of cash. The aim is to thoroughly enhance your vehicle without spending a lot of money up-front; and, hopefully, you’ll recoup the majority of this money when it comes time to sell.

A modified car needn’t be a total financial burden.

Audio System

Head Unit

Let’s assume you’ve bought a vehicle fitted with a plain ol’ radio/cassette head unit – it’s a bit difficult to play your burnt CD-Rs isn’t it? (Let alone those music CDs that you actually bought!)

One of the cheapest ways to get a CD player into your car is to buy second-hand. Police stolen and recovered auctions (see Auction Sweep), local classified papers, web forums and eBay are the best places to pick yourself up a bargain. We’ve seen decent second-hand CD players go for under AUD$80.

The only downside when buying second-hand is you won’t receive a warranty – it’s a case of Buyer Beware. The safest approach is to buy only from people with positive feedback ratings on eBay and popular web forums. This gives you a guide to the seller’s credibility and the quality of their products.

If you live in Australia make sure any second-hand head unit is sourced from an Australian-spec vehicle – units sourced from foreign vehicles don’t have a radio frequency range suitable for Australia. For head units sourced from Japan you’ll need a FM converter, costing around AUD$45 (see FM Frequency Converter). Also be aware that you might need a unit with a power antenna output, a security code and a mounting cradle. You may also want RCA outputs to connect to a component amplifier.

If you’re somebody that plays music from burnt CDs, you’ll need to ensure the CD player can read CD-Rs. Some CD players are marked ‘CD-R’ and their operation manual usually describes whether a unit is CD-R compatible. Failing this, the only way to tell if a particular unit will play CD-Rs is to give it a go – ask the seller to test it for you.

Note that you shouldn’t spend more than about AUD$120 on a second-hand CD unit without comparing prices to new units; decent quality new CD players can now be bought from around AUD$160. In some cases, second-hand units aren’t the best value.

For an article on installing a budget CD system – complete with upgrade OE speakers – see A Budget Sound Upgrade

Speakers and Amps

Let’s say you want a sound system that offers good quality and a bit of kick – something that’ll get you jivin’ when the volume is wound up, but not necessarily a window rattler.

In most instances the top-end of the frequency range (treble) can be enhanced by installing tweeters to augment the existing front speakers. Brand new Jaycar tweeters can be bought for around AUD$60 while second-hand OE tweeters can be scrounged from wreckers at around AUD$10 – the tweeters seen here were removed from a Japanese-market Mazda and come complete with grilles.

Note that most tweeters require a capacitor to stop them trying to produce bass and mid-range frequencies. Tweeters should also be mounted near the base of the A pillar for optimal sound imaging.

And what about bass?

Well, for true bass you can’t go past a 10 or 12 inch subwoofer. Subwoofers can be bought new from around $40 (for a cheapie) to several hundred bucks. For the best performance for your dollar, we suggest any subwoofer with a relatively low resonant frequency and high input sensitivity. Generally speaking, a low resonant frequency means the woofer can reproduce very deep bass. High input sensitivity means the speaker produces high volume for a given input power.

Note that subwoofers are also designed to operate in either a sealed enclosure, ported enclosure or in ‘free air’. A free air sub is the cheapest to install because you don’t need to buy an enclosure – the driver is mounted to the parcel shelf or the seat backrest and uses the entire cargo area as its enclosure. The other advantage is there’s very little extra weight and you don’t lose as much cargo volume. See Cheap, Do-It-Yourself Bass for the installation of a second-hand free-air subwoofer.

Note that a subwoofer requires a fairly powerful amplifier to perform to its potential. The most cost-effective approach is to buy a modest 2-channel amplifier and, where possible, bridge its outputs. Note that, when bridged, the amplifier must be stable operating at 2 ohms (assuming you use a single 4 ohm sub). The 150W x 2 amplifier in this pic is bridgeable and is ideal for powering a subwoofer because of its extra features – selectable bass boost and a variable low pass crossover (which enables only bass frequencies to reach the woofer). The cost? Just AUD$90 second-hand...

Is a Sub-Woofer Really Needed? If you’ve got limited vehicle space, limited money and/or you don’t need thunderous bass, you can opt for some big full-range speakers – 6 x 9s and 7 x 10s are as big as they come. These big full-range speakers can be mounted on the vehicle’s parcel shelf and don’t require a dedicated enclosure; like a free-air sub, they utilise the volume of the vehicle’s cargo area. Big full-range speakers also tend to have very high input sensitivity, which means you can produce good volume without a big amplifier - in many instances you’ll find an amplifier is not needed at all. Starting at around AUD$80 second-hand, it is no wonder 6 x 9s have a reputation for unequalled bang for buck - they don’t give subwoofer-like bass, but they aren’t that far off...

For many people, the addition of tweeters and a subwoofer will satisfy their car audio needs – however, if the mid-range sounds muddy or lacks power you’ll need to look at replacing the existing full-range speakers.

Aftermarket full-range speakers come in a variety of shapes and sizes and you can easily find a set that’ll fit in the factory speaker cut-outs. New mid-range speakers vary in cost but you can pick up a decent set for about AUD$150. Go for the speakers with the highest input sensitivity – this will give maximum possible power for a given amplifier output.

Interior Mods

Extra Gauges

One of the most popular additions to a turbocharged car is a boost gauge.

The latest-and-greatest electronic boost gauges typically feature a ‘peak recall’ function and are reputedly more accurate than a humble pneumatic gauge - but for the majority of applications, they’re not worth the extra dollars.

A pneumatic boost pressure gauge can be picked up brand new from about AUD$40 and brand name second-hand ones (such as GReddy) can typically be bought for around AUD$100 - well under a quarter the cost of a new electronic boost gauge! See Basic Hands-On - How to Fit a Boost Gauge for the Do-It-Yourself installation of a pneumatic boost gauge.

And what about the ever-popular ‘monster’ tacho?

Well, unless your car makes some serious grunt these are nothing but overkill.

If you’re car isn’t fitted with a tacho the neatest and easiest way to get one is to look for a ‘sports’ tacho cluster from the same vehicle. One person we know upgraded their base Holden VN Commodore instrument cluster to ‘S’ spec for only AUD$80. Bargain!

If you can’t source a drop-in sports cluster we suggest a modest size aftermarket tacho. Smaller tachos are easier to integrate into the factory gauge cluster, centre console, on the steering column or A pillar.

Gauge Mounting The most common gauge mounting locations are the A pillar and on top of the steering column – great spots for gauge viewing but terrible for crash safety and even worse for attracting defect stickers. So where should you mount an additional gauge? Well, we recommend using any factory-style gauge location – unused DIN openings or, where available, an OE style gauge pod. This photo shows the active suspension display pod from a Mitsubishi Galant GSR – it’s the perfect addition to the top of a VR4 dash along with a custom faceplate and a suitable diameter gauges. This gives an elegant and integrated look – and at very low cost.

Steering Wheel

If your vehicle isn’t equipped with a driver’s airbag you’re free to replace the existing steering wheel with whatever you like – within the specific restrictions of your State/Territory.

The cheapest way to upgrade a steering wheel is to look for sporty wheels from other cars – start with steering wheels from the same manufacturer and then expend your search into other marques. A replacement steering should slide onto your car’s steering shaft and mesh with the splines. It should also maintain a clear view of the instruments and allow easy finger-reach to stalk controls – oh yeah, and it must also satisfy your local laws regarding steering wheel diameter.

Alternatively, you can opt to improve the look and feel of the car’s existing steering wheel. Any steering wheel can be custom trimmed in plain or perforated leather, a choice of stitch styles and a variety of colours. And, while you’re at it, you can also get the gear selector knob trimmed to match. The total cost to re-leather and ‘baseball’ stitch this steering wheel and knob came to AUD$200. See Complementing Leather for full details.

Whichever way you go it’ll be much cheaper than buying a new aftermarket steering wheel and suitable hub kit.

Vehicles Fitted with an Airbag? Note that it’s dangerous and illegal to replace a steering wheel equipped with an airbag. Your only option is to custom trim the factory wheel.

General Interior Trim

If you own a base-spec version you’re in a great position to make the most of bolt-on upgrades from upmarket models.

Bolt-on upgrades include map lights and courtesy lights, better door trims and more supportive seats. These can vastly improve the feel of a base-spec car – but what if you’re starting with an upmarket model and you still want more?

Well, we suggest a visit to your local Japanese import wrecker to see if they have factory pews from STis, Evos, GT-Rs and the like. These typically cost around AUD$500 - 700 a pair so make sure you measure the seat base pattern of your car and check that they'll suit. If not, you’ll need to fabricate or buy custom seat mounts. See Fitting Budget Seats for Do-It-Yourself seat mounting.

For other interior trimming you’re pretty well on your own – custom work is the only approach.

Speaker pods/map pockets from the front doors of VR-type Holden Commodore can be added to any bare-bones factory door trim (as seen here). You can also improve appearances using a variety of trim materials and a bit of ingenuity.

We strongly suggest keeping your eyes peeled for upgrade parts from other cars. In this pic, a leather gear boot from a late-model Subaru Liberty replaces the dorky rubber boot that’s factory fitted to the Liberty RS. This mod lightened the hip pocket only AUD$10...

Its subtle changes like this that make all the difference.

In Part Two of this series we’ll look at good financial approaches to external modification.