I have been interested in how engine MAF pipes have changed throughout the LSX range. So I thought I'd catalogue then here. The designs have varied for different reasons. Better flow, reduced intake noise, mafless operation and intake tuning (Helmholtz resonators). Well begin with the factory stock MAF pipes. LS1 5.7L Holden VT Series 2 220kw - Holden VY Series 2 245kw HSV VT Series 2 250kw to VY 260kw The stock MAF pipe on original LS1's tapers down in diameter making it quite restrictive in the middle section. Early LS1's had the Intake Air Temperature Sensor (IAT) in the airbox lid. These were latter moved to the bottom of the air intake pipe. LS1 C4B 5.7L HSV (GTS) VT Series 2 to VY 300kw The original Mafless intake pipe. The smooth large diameter pipe helped the Calloway designed HSV C4B 300KW engine deliver air straight from its air box to its larger Throttle Body. A rubber accordian section replaces the area where the MAF sensor sits on all other LS1 engines. LS1 5.7L HSV VY Series 2 285kw This MAF pipe removes most of the accordion rubber boot and the pipe gradually tapers up from the smaller MAF diameter to the larger throttle body diameter increasing air flow. LS1 5.7L / LS2 6.0L Holden VZ LS1 260kw HSV LS2 6.0L Z series 298kw Due to the VZ LS1 moving to a larger less restrictive MAF sensor, Holden upgraded the Intake pipe to a larger diameter, smooth pipe design for increased air flow. It also features a PCV pipe fitting but deleted the IAT sensor from the intake pipe as this was now contained in the updated MAF sensor. This MAF pipe was retained for HSV's 6.0L LS2 engine. L76 6.0L Holden VZ 260kw Interesting now a complex resonator is added to the intake most likely for intake noise reduction. The enlarged volume in front of the throttle body may be for intake tuning. This would also help prevent reversion (air bouncing off the throttle body) going back through the MAF sensor. The VZ Commodore was Holden's first attempts at designing intake resonators adding them to the L76 and Alloytec V6 MAF pipes.