I’m aware, but the Viper’s engine was originally based quite close on the old Magnum which ain’t exactly “exotic V10” material. The Triton also falls in to this exact category as well, it sounds awful compared to most properly engineered V10s. Don’t forget that while the Audi/Lamborghini and Porsche both use split pins, they weren’t based upon a pre-existing V8.
Why do they use 90 degrees for clean-sheet engines when 72 is the ‘natural’ angle for a V10? Is the slightly lower CoG so valuable? 72 is too tall?
To save money.
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How? RomeoReject claims that they aren’t based on an existing V8.
Doesn’t change the fact that if all your moulds are based around 90 degree blocks, it’ll be a hell of a lot cheaper to do another 90 degree block. It’s also worth mentioning, the Carrera GT’s V10 isn’t a 90 degree, it’s a 68 degree (http://jalopnik.com/the-convoluted-history-of-why-the-carrera-gt-sounds-lik-1636980042). For Lamborghini/Audi’s engine, I haven’t the foggiest idea why it’s a ninety, because they didn’t base it off any of their other engines. I would assume the answer is likely packaging. (https://en.wikipedia.org/wiki/Lamborghini_V10)
Lambo/Audi V10 is based on the Audi V8.
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Sorry to be obtuse, but how does that work? I would have thought for a brand new engine parts like the block (and moulds to create said block) wouldn’t be interchangable, otherwise it wouldn’t be a brand new engine.
Although, it seems that all of the 90 degree V10s mentioned do seem to be based off of V8s, so perhaps it’s a moot question. Considering the rarity of cars that ‘need’ V10s, I guess it’s not surprising that a non-V8-based design like the LFA engine (a car which lost Toyota money due to the extreme costs) is limited to a select few supercars.
“There was also some speculation that the engine block of the original 5.0-litre Lamborghini V10 is closely based on the Audi 4.2 FSI V8, which Audi produces for their luxury cars. However, this was denied by AUDI AG, in their official documentation for their 5.2 FSI V10 engine, as used in the Audi S6 and Audi S8 - the Lamborghini 5.0 V10 has a cylinder bore spacing of 88 millimetres (3.46 in) between centres, whereas the Audi 5.2 V10 cylinder bore spacing is 90 millimetres (3.54 in).”
In modular engines like the Ford (And somewhat like the Dodge) the moulds are quite literally two halves of an existing V8 (Four from one and six from another) put together. I would assume it makes engineering considerably easier, as things like coolant passages, oil passages, valley supports, et al have already been designed, rather than having to design them all from scratch.
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The first Lambo V10 5.0 yes, but the 5.2 is nearly identical with the engine from the Audi R8.
Fun side note, the engine in the Audi TT RS 2.5L turbo has a spacing of 88mm. Hmmmm…
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I guess people disagree over the definition of ‘brand new’; I would expect a clean-sheet block and head at least. But again, this seems to be a moot point, as the answer to ‘why 90 degrees?’ is that the vast majority of V10s are actually based off of V8s.
I thought BMW’s V10 has a firing order similar to the Viper?