Alternative power-plants and transplants (GTi, Porsche, Subaru, Audi, diesel etc). Discussion and Q&A last answered over 2 years ago.
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If you want some SERIOUS air-cooled grunt you could always try to shoehorn a Magirus Deutz air-cooled V8 truck diesel in there. That cavernous engine bay suddenly starts to look a bit small!
Brooky.
most likley to an aircraft motor.
They only rev to around 3000 rpm at redline.
Anything more and they require a build.
Unless in Tractor Pulling Spec !
But then they are very short lived.
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