The rolling road results

Buying "After market" performance accessories for your car is an often fraught process. How do you choose the right product? What offers value for money? Does the product do what is claimed of it? How do I find out?

As a way to offer clarity for the average MGF owner, Paul Sharpe and I have embarked on a methodical series of tests on some of the bolt on power accessories that can be easily purchased here in the UK. In order for the tests to be achieved quickly and at an affordable cost to ourselves, we have gone into partnership with the MG specialist press- without whom the results you find here would never have been colated.

The filter tests were performed in partnership with Richard Eaton and Graeme Bishko. We extend special thanks to those who made the tests possible: Martyn Wise, editor of MG Enthusiast, Lesley Smith at Kinnor (K&N retailers), and the K&N R&D department whose rolling road we employed for this investigation (thanks to Scott and Bill).

The full MG Enthusiast report can be ordered from back order (MGE May 1999, Volume 24, No 2), or can be read on-line, reproduced in part on Erik's web page.

Click on one of the below subject headings to view results, observations and interpretions:

Filters used in the tests

1.8 MPi Panel filter results

1.8 MPi Cone filter results

VVC Panel filter results

VVC Cone filter results

1.8 MPi versus the VVC in 57i equipped guise

The importance of cold air

Driving impressions


All the above filter tests were performed in an observer blinded fashion at the Warrington K&N R&D research facility. (All K&N affiliated staff were kept in the dark as to the true nature of the filter fitted to the car to avoid any potential bias from the investigation).

Two cars were utilised during the test, one a 1.8i MGF belonging to Richard Eaton, and the other, a VVC MGF belonging to Paul Sharpe. Temperature was closely controlled for, and each power run was repeated at least three times to ensure reproducibility.

The power outputs quoted above are for the output at the road wheels, not the fly wheel. An estimate of drive train losses was made using a negative power run- around 8 bhp each for both of the cars involved.

Rob Bell.