The PDP engine brought the power of the baffle engine close to that of the schnuerle ported engine. Yes, power demands fuel. I think only Super Tiger, HB, and Clarence Lee bought the right to the PDP port from John Perry

On pipes, it all depends on what you want to do. A pipe can be thought of as a gearbox moving the torque curve around as you see fit. With today's emphasis on noise reduction I'd tend to use a long pipe and set up for the 11K to 13K RPM band.

If you can find them I like the reflex washer design made popular by the OS 46 marine and Hanno engines. I also like the reverse trumpet of the Webra red head.

I had posted some pictures of what the low RPM torque curve can look like I also show what some pipe designs look like. Sorry I don't (can't find) have my Webra pipe.

The top pipe is an FAI F3D Pylon pipe set up to run at 28K rpm. Note the parabolic cones and long stinger and short (no straight section) header.
The second pipe is a 10 cc Hatori long muffled pipe notice the long center section.
The third pipe is the OS Hanno it uses reflective washers instead of a converging aft cone.
And the last is a Hatori steel 15 cc (classic) tuned pipe.

No need to use a pump unless you are going to use an oversized carb. For sport set ups I like to actually drop down in choke size when I use a pipe. I get more than enough power from the super charging effect of the pipe. The smaller carb helps with engine tractability. Long pipes tend to over run the carb makinging it rather difficult to come down in RPM once you are on the pipe. The small carb helps. As I don't think you are going to change the timing to a full pipe exhaust timing this really shouldn't be an issue.

Now for sport, I really like the 1/4 wave pipes like these.

http://www.jettengineering.com/

Look at the Jett-Stream tuned muffler. measure your exhaust stack size and bolt spacing and find one that looks like it will bolt up to your engine.


Friends don't let friends fly nickel,

Konrad