I’ve been watching videos of some F13/F06 M6s and E92 M3s and noticed that they sound very different. I was curious as to why this was the case, because they’re both similar engines.
Both V8’s at 90 degree angles Both have 4.0L of displacements, 4.0L for the S65 and 4.4L for the S63 to be specific. Both use the same Valve Train in DOHC with VVT. Both engine blocks are also aluminum.
Their only real differences is that the S65 is NA while the S63 is a Twin Turbo. Their bore and stroke are also different with the bore being 92mm and stroke 75.2mm for the S65 while the S63 has a 89mm stroke and 88.3 mm bore.
I know some cars do sound different once turbo charged, but they still sounds similar afterwards. Their stroke and bore are so close as well, so I’m not sure that’s but enough to make a difference. Same with displacement.
S65 and s85 were F1 derived. It’s a motorsport engine.
The other M engines that came afterwards like the s63, s55, and s58 are all based off of ‘regular traffic’ engines like the n63, n55, and b58.