Could he possibly be referring to a Honda Type R motor?
I'm sure he's referring to the JDM Honda B18 motor, but it's far funnier thinking about a Rover 25 with a Volvo engine in it which was used in a howitzer gun. 
That's the thing about throwing around random TLAs assuming everybody knows what you mean.
You just look like an idiot throwing about TLAs to most people.
If I'm honest it was the Volvo that came to mind first.
There was a mention of turbo charging said motor, imagine a turbo charged howitzer!
