February 2012 Archives

Modifying Your Sports Car

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I want a fast car!

When I was 15 I got a ride in a friend's WS6. In addition to looking great, it was my first experience with a fast car. I was hooked, and for a while I was convinced I'd get myself a WS6 when I turned 16.

At 16, of course, I didn't have tens of thousands of dollars to drop on a new car. I was very fortunate that my parents bought me a used Honda Prelude, and I showed my gratitude by totaling it a month later when I tried to negotiate a turn too quickly in the rain. If there is anything I learned from the Prelude (other than the fact that it really sucks to wreck your new car), it was that I could perform simple maintenance on a car, such as an oil change, in my garage.

16, and my high school years in general, occurred during the rise of the rice-burner in America. Imports outnumbered domestics at my school and every morning and afternoon featured a soundtrack of coffee can exhausts farting in and out of the parking lot. There was a giant pissing match between everybody and everybody else over whose car is faster.

Most of us were just dreamers with no means. I replaced the Prelude with a Nissan 240sx and sat to work modifying it -- that is, dreaming of modifying it. I was going to convert it to a Turbo Silvia. But I didn't have any money.

Fate (and my own stupidity) eventually took hold and I smashed the 240sx too. I ended up in a cheaper 5 spd Nissan Sentra. The biggest "mod" the Sentra ever received was a transplant of a decent custom stereo that was once installed in the 240sx. But as I drove this beater over the years, I swapped two clutches, and practically the whole ignition system. I started to gain real confidence that I knew how to work on cars.

Eventually, as a young adult, I took out a loan and swapped the Sentra for a Mazda Miata. I didn't have a lot of money, but I had some, and I was soon pouring money into modifying the Miata. It seemed like the dream I always had about upgrading a car was finally coming true. I was so excited that I barely noticed when a professional mechanic advised me not to get into heavily modifying my daily driver -- especially if I am not a professional mechanic prepared to keep it running. I ignored this advice again when a friend with a heavily modified 350z explained his regrets at having destroyed the car's reliability.

I suppose I thought that they were part of a "club" that didn't want new members. In reality, they were just ensuring they would eventually get a big "I told you so!"

I'll build a fast car!

I started with a simple tune-up. The car ran a little smoother, but it was no faster.

I added custom seat heaters. They were a nice mod. But it was no faster.

Being a Texas driver, my Miata was often stuck in traffic on hot days. This led to a number of incidents when the car would overheat and require me to switch from comforting A/C to blistering heat. In went my first high-dollar mod, a thousand-dollar aluminum race radiator combined with an oil cooler. I dropped another $400 on a custom fan shroud with two large electric fans. I felt great about my investment, but I still had problems on hot days. And the car was no faster.

Naturally, any fast car should handle very well. The Miata is known for handling well from the factory, and for being very easy to drive, but I decided to supercharge the handling. I bought upgraded anti-roll bars, dropped 2k on a custom coil-over suspension and spent half a grand on 28 replacement suspension bushings from a performance part manufacturer in England.

I installed the coil-overs myself but was not prepared to tackle the massive task of installing bushings alone. I paid a friendly mechanic with a brand new intake for his car (taking another $400 out of my own pocket) and we spent a day doing the bushings with a real lift and hydraulic press. Towards the end of the evening we were both tired, and when he started using the impact wrench to torque down my eccentrics while the wheels were still sagging, I didn't have much energy left to argue the merits of doing the job properly (while the car was resting on its own weight). Although all the bushings were now installed with preloaded stress, the car felt great, and though it didn't accelerate any faster, it probably cornered faster.

Nevermind that broken part, I'll just keep upgrading!

Before the bushings started to fail, the custom lexan fan shroud was cracking. This gentleman's home-built radiator shroud design was not thought out well. In addition to falling apart, the foam used to seal up the shroud around the edges was melting and forming a disgusting goo on the radiator. I should have stopped there and gotten a real fan shroud, but I was too interested in spending money on more fun parts for the car.

By this time it was clear that I wanted a supercharger. After seeing a deal online for $500 off on an MP62 kit, I put it on a credit card and ended up with a pristine, brand new supercharger in a cardboard box in my closet. Installing the supercharger would be a big ordeal and there was a lot of prep work I'd have to do.

I installed an upgraded header and heat wrapping. The car sounded a little better, and it may have been faster (by a very small amount). But I still wasn't ready to install the supercharger.

In order to support the load of the supercharger, I'd need a new performance clutch. I spent the money on a Stage 3 clutch and decided to get a lightweight flywheel to make the engine rev faster while I was at it. $1000 later I was underneath the car, swapping in the new parts. I thought I would go ahead and replace the rear main seal (which wasn't leaking oil) with a new one. Preventative maintenance and all.

Eventually I decided to get smart and run a compression test on the engine. Bad news -- I needed new rings. That was going to be expensive and would further delay my supercharger installation. But no matter, I was making progress towards my dream. I was going to finish building my fast car.

Unfortunately, dreams are often just that. My car was already less reliable than when I started. I needed frequent alignments to keep the lowered car driving correctly. I was going through tires. And before long, I noticed the car was leaking oil -- from the transmission bellhousing. My brand new $1000 clutch setup started to slip, and then slip more. A year after purchase, its warranty already having expired, I still had the supercharger sitting in a box in my closet.

I must have screwed up the rear main seal. I decided that I needed to replace the clutch. This time I paid a professional Miata shop to do the work. $1000 later I had a new clutch and a resurfaced flywheel. The oil leak had destroyed the old clutch and flywheel. At least the pros did it this time. They replaced my rear main seal again. Surely they would do it correctly.

My fan shroud was falling apart even worse than before. The car started making bad noises when I went over bumps and the handling began to degrade. My suspension bushings were beginning to fail, the result of cutting corners in the install procedure. I poured in yet more money to start replacing these parts as they went.

And then I noticed more oil leaking from the bellhousing. I should have twisted the shop's arm to fix the problem. Instead, I waited a year until the damage was already done.

It's just a freaking money pit!

My priorities started changing. The Miata is a fun car but there were new things in my life. I had turntables and a small but growing collection of music software. I started pursuing a more productive hobby.

I decided to hawk the brand new supercharger in my closet. I sold it at a loss.

I still have frame rail reinforcements, and a set of new rear drive gears for a different ratio. I still have top of the line sound deadening material I never installed. If I'm lucky, I'll be able to sell some of those parts at a loss too.

By now I was just trying to keep the car running as a daily driver. The clutch continued to get worse and I had to replace the $150 dry cell battery with another one after it lasted no longer than a standard battery. (The factory Panasonic battery the car came with was in no way worn out when I installed the first dry cell battery. It was just another "upgrade")

On the way home from work one day, a driver in a Tahoe was too busy chatting on his cell phone to notice my Miata in the lane next to him, and so he slammed my car into a guardrail. Both of our insurance companies quickly reminded me that the thousands of dollars of custom work done to the car did nothing to increase its actual value. I knew this before I started modifying the car, but it was still a punch in the gut.

You told me so!

In the end, I caused the Miata enough problems that it actually became slower.

It's true what they say. Modifying a car is an expensive, time consuming proposition. Cars are already depreciating assets; adding custom parts to them makes it even worse.

When cars leave the manufacturer, assuming the vehicle is of reasonable quality, it will have reasonable durability. Virtually everything you do to "customize" beyond the factory specs will negatively impact the longevity. Custom parts break much more often than factory ones, and custom parts often break the factory parts you plug them into.

If I had it all to do over again, I would have upgraded the stereo and installed the seat heaters. I wouldn't have upgraded anything else. I should have just fixed problems when they came up. But like so many things in life, I learned this lesson the hard way.

Super Special Update!

The heat shield caught on fire. It might have burned my car to the ground, and maybe my garage and some adjacent apartments as well, had I not happened to pop the hood right after it happened. I've been assured that the heat shield is rated to thousands of degrees.