fastmoverP1AH

I have heard that there can be problems with the MAF sensor when changing the air filter on the P1. Does anyone know anything about this. If it is true are there any suggestions plus if not what suggestions for air filter to buy HKS blitz etc.

john banks

3 issues:
1. damaging the MAF sensor requiring £70 replacement sometimes repeatedly
2. leaning out and advancing the already fairly lean and advanced P1 fuelling and timing
3. filtration quality

For an induction kit, IMHO, K&N 57i is a good bet for hopefully not doing too much of either 1 or 2 and being reasonable at 3, but the standard 57i draws in hot air from the engine bay. Some, including me consider this signficant.

I have seen wild fuelling changes with HKS and APS induction kits (serious amounts of extra fuel - about 20% in both cases required to get back to where it started).

Depending on who you believe HKS and Blitz tend to damage MAF sensors, again there is disagreement.

If you are keeping your P1 relatively standard then keep the original airbox and filter IMHO.

If you are going over 320 BHP change it to something to suit whatever FMIC and ECU you will be using.

A speed-density ECU such as a Link or Motec will enable you to get rid of the MAF sensor and then you remove a flow restriction and do not rely on a potentially unrelibable part in a modified intake to blow up your engine. Some would argue that a MAF based system does drive better on part throttle and is more accurate at fuelling in different situations. OEMs use it for this reason and also because of emissions compliance.