There should be some signs of die grinder work (or very polished) at top end of port
if streep ported.  If it looks like the slightly grainy casting, it hasn't been
ported.
 


 
     I was wondering if anyone knows how much less power to expect from an engine
with 86 n.a. rotors as opposed to one with the later, lighter, higher
     compression rotors.
     I have a set of 4 port end-housings that I will run with n.a. rotors like
Tracy's latest motor built by Bruce T. The thing is that I have a good set of 86
     n.a rotors on hand and would have to purchase a set of later rotors and they
aren't exactly cheap. I'm wondering if the increase in power would be
     enough to make it worth it.
      
     Also can anyone tell me how to tell if my end-housings have been street ported.
The port looks pretty big but It may be right for a 4-port. Is there a
     measurement I can take to tell? The engine had been recently over-hauled and may
have been ported then. Unfortunately this motor swallowed
     something. I don't know what because there's nothing missing from the rotor or
chamber. But it did a number on one rotor and the rotor housing. The
     end-housings look fine.
      
     Which brings me to my next point. I'm looking for one 4-port rotor housing in
excellent shape if anyone knows of one. Thanks, James Phillips



There should be some signs of die grinder work (or very polished) at top end of port
if streep ported.  If it looks like the slightly grainy casting, it hasn't been
ported.
 
There will be very little difference between 86 (9.4 CR) and 89 - 91 (9.7 CR)
rotors.  Also remember that you will have to use late model counterweights if you
change rotors.   My reccomendation ---  save your money.
 
Tracy             

Whatever you did with your email program Tracy PLEASE go back. It is very difficult
for me to forward.                  
 
Paul Lamar
 
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