Yes, Imagine Auto.
The fuel head mod has your heads passages cnc'd bigger to allow more fuel to flow through it. The pipes and injectors are not limiting fuel, only the fuel head. When you go over 400bhp the fuel pressure can drop causing a lean condition due to the fuel head.
Euro heads are supposed to flow more than a US head, but once they are both modified the US one flows more.
I have a modded US head
1981 UK 930. G50/01 shortened, 964 3.8RS Fibreglass Body Kit, 18" Alloys 8.5" F & 10" R, 225's F & 285's R, Special Colour Metallic Blue Paint, FIA Sparco Evo's, A/C and Air Pump removed, Electronic Boost Controller, GHL Headers, Tial46 WG.
Fitting - New service kit.
Needs Fitting - Innovate XD-16 Kit, Kokeln IC. Stephen's K27 HFS, EVO Intake Assy & his Modded USA Fuel Head.
1983 UK 911 3.2 Carrera Sport Coupe. Black, Black Leather with Red Piping, Black Alloy Gear Knob, K&N Air Filter Element, Turbo Tie rods.
Needs Fitting - K&N CO Sensor, Round A/F Dial Gauge, Factory Short Shift Kit.
Last edited by NathanUK; 12-30-2006 at 01:35 PM..