The car Bibles product reviews: Pulstar Pulse Spark Plugs.
Pulstar Pulse Plugs
Tested October 2008 to February 2009
Pulstar spark plugs make some unique claims about their technology and what it can do for your car. Essentially they're billed as the cheapest, quickest way to more horsepower and better fuel economy. Sounds familiar? The difference is that Pulstar's claims aren't wild. They don't claim to double your gas mileage, or add a gazillion horsepower. They claim modest gains - up to 7% - which is realistic. Pulstar do several plug types to suit all different vehicles from motorbike to cars to SUVs and 4x4s. You can use their website to lookup a suitable variant for your own vehicle. Here I tested the be1 plugs. Pulstar claim that the technology inside the insulator section of the plug is what makes their product different. In a normal vehicle high tension circuit, it takes time for the voltage to build up to the point where the spark plug can discharge it with a spark. Now when I say "it takes time", I'm talking milliseconds, but according to Pulstar, those milliseconds count - it's wasted energy. Their plugs have a capacitor-like circuit in them which stores the so-called wasted energy in the buildup to the spark, then uses it all at once to create a more powerful spark. The theory is that a better spark means better combusion, which can give you performance or fuel economy gains, depending on whether you're driving normally or hooning around like a madman.
Below is a cutaway of a Pulstar plug (thanks to Ramblerdan at the EOC). The insulator didn't like being taken to pieces, and the grinder pretty much ruined the rest of the plug so it's difficult to tell how the innards are supposed to be different to any other plug.
The test vehicle for this product test is a Honda Element. The Element isn't exactly a performance vehicle - it's a porky SUV with the aerodynamics of a tower block. It has Honda's venerable 2.4 i-VTEC engine in it though, so it's no slouch considering it's size. However, it does represent a factory vehicle with no performance mods; one that is used every day for everything from hoofing it up mountain roads to go skiing, to long-distance road trips. In other words, it's exactly the sort of vehicle the average driver might own. To test the Pulstar claims, two things need to happen. First - fuel economy before-and-after, and second, outright horsepower and 0-60 times before and after. Fuel economy is easy - I keep records of the Element's fuel economy at every fill up using trackyourgasmileage.com:
Performance is a little more difficult unless you have a deserted road with no police, or a friendly motorsports track.
To get a good average for all the figures measured, the key is to get a bunch of readings, eliminate the highest and lowest values, then average the rest. The performance testing was done using a G-Tech performance meter - an easy-to-use product that has proven to be within a couple of percent of more traditional measurement methods. Below is a table of ten 0-60 times, ten horsepower runs and seven mpg calculations, sorted lowest-to-highest. The mpg figures are for the last 7 tanks before the test began. These are real-world figures, not manufacturer-inflated ones.
Important note: Because this test was done with an automatic transmission, the horsepower results are slightly skewed. The important number will be the difference between the before and after horsepower values - not the values themselves - because each test was done in near identical conditions with the same equipment, vehicle and testing procedure. Note - the rows are independent of each other. ie. a horsepower measurement does not correspond to an mpg calculation or 0-60 time.
Eliminating the highest and lowest values for each reading, and averaging the rest gives the following 'before' calculation with stock spark plugs.
The Pulstar test lasted 4 months which allowed a good spread of time for them to bed in and perform on a daily basis. (Pulstar claim it could take a couple of tankfuls of gas for a car's engine management system to adapt to the new plugs.) The 'after' tests were done in the same location as the 'before' tests with near enough identical atmospheric conditions. As before, the runs were done each way to average out any prevailing wind. The mpg figures represent the last 7 tanks with the Pulstar plugs in the engine. The results were as follows. As above, the rows are independent of each other. ie. a horsepower measurement does not correspond to an mpg calculation or 0-60 time.
As before, eliminating the highest and lowest values for each reading, and averaging the rest gives the following 'after' calculation with the Pulstar plugs.
Conclusion : "Designer" Spark Plugs.
If you've never changed your spark plugs, putting almost any brand of new plug in your engine will yield some change to your vehicle's characteristics - normally a slightly increased gas mileage and slightly increased horsepower. With the Pulstar plugs, the average gas-mileage went down slightly over the course of the test. This bears out similar reports from other group tests of these spark plugs published elsewhere on the web.
Horsepower did go up but only slightly using the testing method here. As I said above, it's not the absolute value that is important - it's the difference between the before and after figures. In this case half a horsepower equates to about 0.4% difference. Any sort of dyno testing whether it be rolling road or dynamic in-car testing like this will typically have an error tolerance of about 5% so the difference in horsepower results in this case is negligible.
I rated the plugs as 2 stars because they're good quality plugs and make fine replacements for anything you might have in your engine right now. But they simply do not seem to live up to the claims made in the advertising.