Blown Out of Proportion

The cycle of owning an old car goes something like this: First you find and purchase the car you want, then you begin driving it around. The next logical step is to start fixing things as you go, because 100k+ miles have taken their toll on the mechanical bits. Once everything is mechanically sound, the cosmetics are dealt with and the car becomes a nice driving example. For some people that’s enough, but Taylor Griffith wasn’t content, so he made it his mission to ensure his e34 540i was anything but typical.

The Hunt for Red October

With the e34 being out of production for over 20 years, finding aftermarket specialty parts can be a tall order. For several years, Taylor had always wanted to get his hands on a smog legal Dinan supercharger kit for his m60 equipped car. By no means are they common to find, but living fairly close to Dinan’s headquarters meant classifieds for cars and parts pop up every now and again. When an e34 540i with a Dinan supercharger was listed on Craigslist, Taylor tried to get the owner to sell the supercharger separately from the car, but the owner wouldn’t budge. Eventually the car sold and that was that.

A few years later, the same car Taylor had been chasing appeared for sale yet again, but this time the car was in a state of great disrepair. Surprisingly the supercharger was still intact along with a host of other trick parts (including an extremely rare set of Dinan Schrick camshafts). Ultimately he purchased the entire car and parted out what he didn’t want. After three years, the Dinan supercharger was finally in Taylor’s possession.

Prepping for Boost

Now I could tell you that the story ends there and everyone lived happily ever after, but that wouldn’t be interesting now, would it? Taylor could have just slapped on the parts and cross his fingers that everything wouldn’t blow up, but that would have been a large gamble, especially after all the trouble he had gone through to find the kit. Immersed in a small sea of packing peanuts, the Dinan Powerdyne supercharger was shipped to 928 Motorsports of Wisconsin for both a rebuild and a pulley upgrade, bumping boost up from 6 to 7 PSI.

With the help of friends over the course of a couple weeks, Mr. Griffith finally got his green executive sedan running with forced induction. As to be expected, there were a few hiccups before it was running correctly. A kinked radiator hose caused a geyser of coolant to spray twenty feet into the air, and a poor fuel mapping problem would cause the car to backfire until a 3 ohm resistor was spliced into the MAF wiring. Look at it this way: it wouldn’t be an old car if something wasn’t on the verge of bursting into flames.

Blower Motor

Before the supercharger, Taylor’s 540i was had fairly stout performance thanks to an aggressive 3.64 rear end, but ~300hp was only going to do so much for the 3700lb e34. With the “puffer” installed, the 4 liter v8 fires up smooth as always. There’s a slight belt whine, but only audible to those searching for the noise. Around town the 540 is still easy to drive. Honestly you probably wouldn’t notice the supercharger unless someone told you. But it’s 5000 RPM where things start to get interesting.

As day-to-day traffic continues to swell, finding a clear section of road on the San Francisco Peninsula has become quite difficult. Once we found the right stretch of pavement though, nothing was held back. Below 5 grand, the 540 feels like it’s propelling itself naturally aspirated, as it’s the same old song and dance everyone has come to know. Once the tach starts its approach towards 6,000 RPM, a rush of boost comes surging into action, stopping only because the 7,000 fuel cut says, “Woah there cowboy!”

It should be noted that the Dinan supercharger is a centrifugal unit, so it sits on the side of the engine not unlike an extra engine accessory (as opposed to a Roots-style). Its power delivery is fairly similar in feel to a turbocharger. The result being that this setup is good for freeway pulls where it has time to build boost. The benefit is that you don’t have to worry about the car getting too squirrelly unless you’re committed to mashing the accelerator. The downside is that the extra power is only apparent in the final 20% of the rev range. Supposedly the donor car dyno’d 448 wheel horsepower and 380 lb-ft of torque, but the butt dyno thinks Taylor’s car is somewhere around the low 400 crank range, meaning it’s about as quick as an e39 M5.

So all that work for some more top end? Not so fast. In order to appease the neighbors, Taylor’s 540 received a conservative muffler that was done as a quick fix. We’re led to believe the exhaust merge into a single 2” pipe is choking the long distance runner. Off to the exhaust chop…err shop.

The quiet Magnaflow was tossed, and in went two SLP Shotgun resonators and a custom H-pipe. Starting the 540 with its new exhaust was met with great excitement. Not only is the volume back at full blast, the note changed for the better. As our friend Willum has pointed out in the past, European V8s tend to sound more restrained than their Red, White, and Blue counterparts. This time around, the Bavarian 32v is back with a bark that will make the most patriotic of muscle car owners proud. The better flowing exhaust seems to have smoothed out the power delivery too. We still think some dyno time and a custom tune would greatly help the 540, considering the base tune is over 20 years old and originally intended for an automatic transmission. Software has come a long way since the days of MS-DOS.

Now that T-Griff has officially boosted the e34, it seems like there’s not much left to do. In a certain sense that’s true. The real answer though is cars are never done. Whether it’s this 540 or another car, he’ll be back at it…and probably set off a few car alarms in the process.

-JC