just a quick question I'm inquiring to see what the original bolt pattern is for Lamborghini Countach... Really appreciated
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original countach bolt pattern. ..?
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Hi Bottlefed, I have OEM wheels and they measure 70mm between the adjacent holes and 114mm between centres of holes across to the other side, not sure what that is in pcd .It is the same as a BMW 1988 750 e32 just checked it in the driveway, if you need other measurements just ask, here is the off set front says 11.75mm rear is 20mm centre hub hole is 70mm at face.

hi Lamboillinois, I always wondered how do they arrive at a figure of 120mm I have the wheels in front of me and nothing measures 120mm just found this definition of pcd Pitch Circle Diameter (PCD)
Pitch Circle Diameter (PCD)
The P.C.D. can be defined as the diameter (in millimetres)
of an imaginary circle drawn through the centre of the stud
holes on the wheel and/or the vehicle wheel hub.
But what i'm measuring is the pcd and its definitely 114 across in a circle.
I have heard for years the Countach wheels were 120mm, but when I got mine they measure 114.and they are genuine OZ from an 87 Countach.
But the internet is full of mis quoted figures. so I will go with what's in my hot little hands, it just leaves me somewhat confused because I have also heard of BMW being 120 also and the Original Countach used BMW 7 series hubs. and the E32 in the driveway definitely measures 114. as does the 1996 e38 750Last edited by Lambolex; 01292014, 11:15 PM.
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When measuring a 5 bolt pattern you cannot measure from one hole to another. You have to measure from one hole to a spot directly opposite it that is actually half way between the two holes on the other side. Your 114 is probably actually 120.
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Measureing 5 stud pcd
Thanks Guys for the info, looks like there are many ways to measure it.I have been digging for a method that works and this seems the most accurate to date. and as the adjacent studs measure 70mm between, if you multiply by the 1.7012 it is close enough at 119.84 to the 120mm quoted above.
From this forum
Measuring the PCD of 5 stud bolt pattern.  4WD Chat  Australia4WD Forum
Here's another method that's got some science and geometry about it, where you measure between the 2 holes shown, to give you X, then multiply by a constant of 1.7012 to give you the total PCD.
5 HOLE WHEELS
Measure the distance X between the centres of 2 ADJACENT holes and multiply by 1.7012
I gather this was calculated by constructing a right angle triangle from the wheel hub centre to one of the wheel stud centre holes and a perpendicular line down to horizontal line constructed beween the lower stud hole centres.
Then calculate: Constant = 2(.5/sin 36 deg), which is 2(0.5/0.58778), which equals 1.7013......yeah, I should have known......sure..
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