How much extra under bonnet clearance does a post facelift bonnet provide vs pre facelift? Thanks John
I have a facelift bonnet in my garage waiting to be installed and a pre-face lift on now. I will measure for you when I get home from work today
How much extra under bonnet clearance does a post facelift bonnet
provide vs pre facelift? Thanks John
I believe they BOTH provide extra clearance, just in different areas. The
pre-facelift has a broad raised area that provides perhaps a half inch extra
clearance over more than half of the entire engine compartment. The facelift
has a narrow hump down the middle that provides perhaps an inch or two of
extra clearance, but only over an area that’s perhaps six inches wide.
The pre-facelift was obviously designed for the V12. In fact, I think the
early 3.6 cars had a hood that looked kinda like the facelift hood, which
would seem to indicate that the 3.6 and 4.0 engines require that center hump
for some reason. The reason is not obvious to me since those engines are
slanted, the head is actually over to one side.
With the facelift, the V12 went with the center hump as well. I have
postulated this might have to do with the A/C compressor change. The
pre-facelift V12 used a Harrison A-6 compressor that was long and narrow
and fit tightly within the V. The facelift cars use a Sanden compressor which
is widely considered a better unit, but it is a bit larger in diameter and might
therefore stick up more right in the center. Still, the fact that the facelift hood
fits over the V12 at all perhaps indicates that the broad raised area of the
pre-facelift was for styling rather than clearance. I don’t believe anything
else about the facelift V12 engine changed heightwise, although the air filter
housings might have.
Remember that the engine bounces around on its mounts. Just because the
hood clears when sitting still doesn’t mean you won’t end up with an
unsightly bump in the hood when you tromp the throttle.
– Kirbert
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Hi Kyle, any measurements? Thanks John.
Sorry, it totally slipped my mind. I will get them for you today. Apologies
At the lowest point of the hump you get an additional 3.8cm at the highest point it it about 6cm. This is without the liner under the hood
The hump is more visible from the top, hopefully the picture illustrates where the hump starts
Much appreciated. Thank you.
No worries, apologies for the delay. If you want more pictures feel free to ask for anything specific, I wasn’t sure exactly where on the hood you need the extra clearance