[OFB Cafe] Checkin' out the Café

[Chris Olson]

From: Timothy Butler 
Sent: Wednesday, July 09, 2008 4:46 PM
To: An Open Discussion Forum on Just About Everything,Especially for Techies. 
Subject: Re: [OFB Cafe] Checkin' out the Café

Yikes! Good thing indeed. Now tell me -- this is something I've been wondering about -- why do boats and the accompanying motors cost so much?

Because people who can afford them will pay it.

I was looking at a boat a while back and remember thinking, "I could get a really fine car fully loaded for that price," and it wasn't even a particularly huge boat.

Well, they're expensive to build too, and actually more complicated than a car.  My outboard motor was $19,000 alone but a big outboard powerhead is more comparable to a NASCAR engine than a street car engine.  Mount your car engine in a boat and run it at wide open throttle at 6,000 rpm and it would maybe last 10 minutes, not to mention the fact that it would have about as much power as a dead pig since it's not cammed right for marine use.  All but the most exotic automotive engines can only put out maximum power for a very short period of time (usually less than a minute on the dyno) before they either overheat or break something.

This doesn't mean automotive engines haven't been used in marine applications, such as the Chevy 350 (5.7L) in the MerCruiser stern drive.  But it's got a lot more expensive parts in it with a marine application.  In a marine engine
  a.. you get a forged steel crank and rods instead of cast 
  b.. you get forged pistons instead of cast 
  c.. the pistons are run at around .008" skirt clearance instead .0015" like they are in automotive applications 
  d.. you get a 4-bolt main block that has considerably more iron in it than an automotive block 
  e.. you get an oil pump that can continuously deliver 10 psi of oil pressure per 1,000 rpm of engine speed instead of a pump that can only make 45 psi, aka a car engine 
  f.. you get water cooled manifolds since the manifolds used in automotive applications would get so hot they'd glow red and either melt or warp 
  g.. and many, many other differences that all increase the manufacturing cost of the unit
--
Chris