Bosch 521 Super 4 Spark PlugFeaturing a unique state of the art design, the Bosch 521 Super 4 Spark Plug results in improved engine smoothness and acceleration.
Bosch 521 Super 4 Spark Plug Extra Info
- Superior engine versatility
- Electrode gap adjusted ex factory
- Noticeable improvement in acceleration
- Significantly improved engine smoothness
Additional InformationPlease check with your vehicle manufacturer or workshop manual to confirm the suitability of this part for your vehicle.
Hex Size: 16 Thread Length mm: 25 Thread Size mm: 14 x 1.25
Bosch 521 Super 4 Spark Plug x4
Cat code: 970582
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ReviewsBosch 521 Super 4 Spark Plug x4 5 5Great product, would recommend Car was running a little off and was due a service, so decided to pay the extra couple of pounds and try out these plugs. So glad I did, they have made and noticeable difference instantly. I live in a hilly part of West Yorkshire and there is far greater power when going up hill now, with less need to change down the gears. All in all the car feels smoother, with more power throughout the whole range. I would definitely recommend these plugs 02 September 2012A good product I can feel the difference while driving. I am getting more power. 05 April 2012Average Thougth i'd give these a try as the old motorcraft ones were getting tired and to my surprise there was no difference in performance apart from the misfire disappearing and economy the same so don't pay out thinking these will make your car go faster as they are no better than the cheaper ones. 18 February 2012Bosch Super 4's Brought a set for a 02 1.6 Focus didn't solve the issue I had with the car but what a diffrence they have made acceleration is so much smoother would recommend to anyone. 06 February 2012Cool stuff :) Got on time and work well tho i though the combustion would be more powerful; can only notice the difference between the 1 electrode spark plugs and the 4 electrode's when driving up a hill. 18 July 20101-5 of 5
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