> 
> Re: Jack's venturi effect -- have never seen the "cap" you mention (I'll look
> real close at the pictures tonite) but I would sooner guess it is to cut down
> the number of grass and leaf fires when parked.
> B.
> 
As I said, it was just a guess.  We could both be right for that matter.
Here's a "picture" of it, though:

                      --------\
                                         |
                                         |  <- tailpipe
                                         |
                    ---\             | 
                           |             |
                           ------   <- end of the tailpipe
                              |     |       <- two iron "straps" on either side
                           ------   <- flat "cap"

If the purpose of it was to deflect the heat so as not to start grass 
fires then why not just set the angle of the pipe at 45 degrees to
lengthen (cool) the distance the exhaust has to travel?

Jack
jackr@starfleet.scs.ag.gov