I was wondering whether the oem M5 camshafts are the same as found in the E39 540 v8 engine?
Anyone have any info?
thanks
Tin
I seriously doubt it. More lift & duration is possible in motors with more cubes without degrading driveability. The 540 motor has a flatter powerband & red line is around 6K RPM, despite having the same valve sizes, headers & cats. Better induction and cams are the major power-adders on the M5. The extra cubes are only good for about 10% gain. I think an M5 motor with 540i cams would basically flatten out around 5500 RPM. The 540i cams are very conservative and optimized for midrange. The powerband suggests they are less aggressive than a '90's Cadillac Northstar or Ford 32V Lincoln/Mustang motor.
I seriously doubt it. More lift & duration is possible in motors with more cubes without degrading driveability. The 540 motor has a flatter powerband & red line is around 6K RPM, despite having the same valve sizes, headers & cats. Better induction and cams are the major power-adders on the M5. The extra cubes are only good for about 10% gain. I think an M5 motor with 540i cams would basically flatten out around 5500 RPM. The 540i cams are very conservative and optimized for midrange. The powerband suggests they are less aggressive than a '90's Cadillac Northstar or Ford 32V Lincoln/Mustang motor.
So M5 cams in a 540i wouldn't be feasibly possible?
So M5 cams in a 540i wouldn't be feasibly possible?
thanks guys..
Swapping the dual Vanos M5 cams swapped into a later dual vanos 4.4L 540i or 4.4L/4.6L X5 may be technically possible. Without checking, I think it's safe to say that Vanos and non-Vanos cams differ, so earlier E39 cars will not be swap candidates.
It would probably be a stupid idea because the non-M induction system is sized for about 300 HP (in normally-aspirated form) & tuned for low and midrange power (torque) & efficiency. Installing an aggressive cam could actually slow the car down, unless accompanying componentry is upgraded or modified for efficiency at elevated RPM!! A big cam will definitely cut low end power and it may not be able to coax enough air flow thru the modestly-sized standard throttle body, MAF & intake assembly above 5K RPM to produce off-setting gains. This is assuming the CPU bandwidth & injectors can flow more fuel, at a higher RPM. I am not sure if fuel augmentation methods are needed for supercharged 540i kits. Elevated fuel rail pressures, CPU tweaks or larger injectors may or may not be needed. "540is" can probably shed some light on this subject.
Swapping one or two go-fast parts has been a poor idea since the 1980's. Ford 5.0L HO owners learned this real fast after swapping a Cobra cam into their stock motor and seeing a 5-10 HP gain on top and a 5-10 HP loss on the bottom. The car was no faster and it felt like a dog under normal operation. This is because modern engine assemblies are tuned and matched to provide optimal efficiency within a certain operating range. This is the beauty of a bolt-on blower setup; it allows the engine to function in the same operating RPM range while providing greater power across the spectrum.
The 4.4L heads appear to be good and capable of high flow. I think an aftermarket intake and other induction mods would be key to gaining elevated RPM power in the non-M V8 motor. A good intake might uncork 25 HP and show big gains from 5500 RPM thru 6500 RPM. The 6K RPM ceiling in the 32V BMW 4.4L V8 is not the least bit impressive. Twenty year old cast iron pushrod EPA-spec motors offer a similar powerband.
Last edited by Lscman; 8th February 2005 at 18:32.
Swapping the dual Vanos M5 cams swapped into a later dual vanos 4.4L 540i or 4.4L/4.6L X5 may be technically possible. Without checking, I think it's safe to say that Vanos and non-Vanos cams differ, so earlier E39 cars will not be swap candidates.
It would probably be a stupid idea because the non-M induction system is sized for about 300 HP (in normally-aspirated form) & tuned for low and midrange power (torque) & efficiency. Installing an aggressive cam could actually slow the car down, unless accompanying componentry is upgraded or modified for efficiency at elevated RPM!! A big cam will definitely cut low end power and it may not be able to coax enough air flow thru the modestly-sized standard throttle body, MAF & intake assembly above 5K RPM to produce off-setting gains. This is assuming the CPU bandwidth & injectors can flow more fuel, at a higher RPM. I am not sure if fuel augmentation methods are needed for supercharged 540i kits. Elevated fuel rail pressures, CPU tweaks or larger injectors may or may not be needed. "540is" can probably shed some light on this subject.
Swapping one or two go-fast parts has been a poor idea since the 1980's. Ford 5.0L HO owners learned this real fast after swapping a Cobra cam into their stock motor and seeing a 5-10 HP gain on top and a 5-10 HP loss on the bottom. The car was no faster and it felt like a dog under normal operation. This is because modern engine assemblies are tuned and matched to provide optimal efficiency within a certain operating range. This is the beauty of a bolt-on blower setup; it allows the engine to function in the same operating RPM range while providing greater power across the spectrum.
The 4.4L heads appear to be good and capable of high flow. I think an aftermarket intake and other induction mods would be key to gaining elevated RPM power in the non-M V8 motor. A good intake might uncork 25 HP and show big gains from 5500 RPM thru 6500 RPM. The 6K RPM ceiling in the 32V BMW 4.4L V8 is not the least bit impressive. Twenty year old cast iron pushrod EPA-spec motors offer a similar powerband.
So your saying doing a cam upgrade on a 98 540 is not a good idea?
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