A 928 is a V-8.  4 cams, 32 valves and about 275hp from the factory.  A very fun car but a eminence nightmare..Electrical system from Hell.

You should be at least a millionaire if you even think of racing.  That would get you in the door as a "poor cousin" racer.  Auto racing, on anything above the local oval, is fairly money dependent.. "Nothing beats cubic dollars" is the basic rule there, and a million?...chump change in that world..There are weekend Porsche Club of America club racers who spend more than that yearly, on a couple of club races..

But, speaking of flat 8 Porsche motors, one of the 996 997 water boxer 6 bangers would really fit well into a Van..You can buy a crate motor from Porsche for about $60k that will deliver over 400 hp to the wheels, without a turbo!  The Twin Turbo puts out 500+... 
   The motor I ran in my 928 was built with a stroker crank and 8 individual throttle bodies, titanium con rods..crap like that, and it put out 575 rwhp on the dyno..again, normal aspirated...A little pricey,(around $20k per motor) but nothing like the factory Cup car motors at $60k.  The Cup car motors call for 'refreshing' at 100 hours...I got over 3 seasons from my big 6.5 liter 928 before I lost the oil in an 'agricultural excursion'...That was it for my racing career...ran right out of my savings...fun though..
  "cubic inches without cubic dollars= an Ex-racer"
  Don Hanson