PROJECT CARS: BIG Bang For Buck On Project 944: NGK Iridium Spark Plugs

As part of the on-going mission to improve the quality, longevity and performance of our auction-bagged Project 944 Porsche (using the absolute limit of our personal engineering prowess it has to be said), we thought it would be simple and indeed pertinent to replace the existing (no doubt manky and untouched for months/years) spark plugs with something with suitable class and gravitas fit for a Porsche.

Welcome NGK Spark Plugs, and more specifically a set of four of their tech-loaded NGK Iridium IX bad boys (Model BPR6EIX for the 944 to be exact).

NGK say their Iridium spark plugs currently represent the “highest-quality technological solution to providing spark,” or bigger bang as I know it (of said suck, squeeze, bang & blow fame). These trick plugs feature an iridium-alloy on the middle electrode, welded on in a special process using laser technology.

And if that isn’t geeky Porsche pub points, I don’t know what it is!

One of the world’s hardest metals, the precious metal that is iridium starts melting at a temperature of (a pretty barmy by anyone’s standards) 2450°C – making it highly resistant to spark erosion. And so by using these plugs, NGK promise the service life is doubled on average in comparison to standard nickel spark plugs, and who can argue with that logic?

They also say more ????, better fuel economy and smoother engine running is possible, along with an improvement in throttle response and maybe even the chance of liberating a few ponies from the dusty old stables too. I’m in…

On an old-fashioned, simple, mechanical, yet well-engineered, normally-aspirated lump like the Porsche 944’s 2,479cc, spark is the No.1 source of power (as it is for any petrol engine). The spark plug is responsible for igniting the air-fuel mixture in the combustion chamber of petrol engines. And it is of course this combustion process that creates engine power, ultimately determining how fast you can send your vehicle down the road.

And with a level of know-how stretching back to the 1930s, decades of motorsport experience from F1 to grass roots and marine and having manufactured over 1,000 types of plugs for over 92% of the world’s market, NGK properly understands their specialist market.

They know for example that in order to make sure the combustion process run as smoothly and powerfully as possible, the spark delivered by the spark plug must ignite just before the piston reaches its highest point and the compression is at its greatest. And that level of engineering know-how, vast experience and the known levels of R&D and manufacturing skill they offer is way above and beyond what our humble Project 944 asked for… but we’re very happy to tap into it anyhow.

Back on the driveway of Road HQ, the old plugs come out (with a fight it has to be said, over-tightened as they were) and are absolutely filthy – so coked-up in fact, I am surprised they have not been arrested. Good riddance.

The NGK iridiums pop in snug as a bug in a rug and are certainly now the shiniest part on the Porsche, even if (buried deep in the half V8’s cylinder head) you can’t see them…

What you can see (or rather feel) though is what these incredible plugs do – right from the first crank of the engine.

To our great surprise back at the auction pick-up, Project 944 started first time and has ever since – with a small delay.

Post-NGK fitment, the slightest touch of the ignition key instantaneously fires the 944’s engine into life with verve, idling sweeter, flatter and better than ever. Maybe that’s just because they were clean I thought… but how wrong I was…

Out on test, I have never known anything like it for such a simple part. Even the K&N air filter’s transformation of this engine is not in this league (and that is saying something). How such a simple component swap can boost a car’s performance to this level is beyond me. All I know is inside those four tiny hunks of shiny metal must be nothing short of witchcraft – because the difference before and after is night and day.

The throttle response – right across the rev range – is massively, massively improved. The engine feels that much smoother, it honestly feels like it’s been in for a full re-build! And the mid-range kick and top end rpm hit is literally 20% better I would argue – completely unscientifically, but with decades of performance testing in cars, via the seat of my pants.

Coupled with the K&N air filter and the car’s existing free-flowing, rorty, Powerflow exhaust, I would be very surprised to see this engine produce anything less that 170bhp now, when it felt closer to sub-150 before. And it’s clearly running more efficiently too, as even with a heavier right foot enjoying the extra poke, the fuel needle is staying up. Bravo NGK! You know spark, or rather bang for your buck.

And all of this goodness is before we put the Ravenol full synthetic oil in to help the engine perform better still! Happy days for Project 944… so far… stay tuned for more soon.


Spot the difference – Old Vs new (NGK)…