Scooterotica

Did a port map for 3 Lambretta cylinders, a 225 reedvalve, a 200 reedvalve and a 225 piston port. I don't want to say which is which just yet, but i found the results quite interesting when i fed it into the port-time-area software for analysis.

See what you techy gurus make of the graphs, i'd be interested to hear your thoughts on theoretical power delivery, port timings, rpm, and to see if you can guess which is which.

Red bar is exhaust angle area and blue is transfers.

Exhaust and Trans port timings and blowdown in degrees shown in top left corner.

Angle area on vertical axis, rpm on horizontal.

42

Avantone wrote:42

You want chips with that?

Avantone has read "the hitch hikers guide to the galaxy"..................

drunkmunkey6969 wrote:See what you techy gurus make of the graphs, i'd be interested to hear your thoughts on theoretical power delivery, port timings, rpm, and to see if you can guess which is which.

It's interesting how the red bar turns green when it meets the blue bar.

Matty wrote:
It's interesting how the red bar turns green when it meets the blue bar.

Yes, i thought yellow turned blue green, not red.

sean brady scooters wrote:Avantone has read "the hitch hikers guide to the galaxy"..................

Ahhh, i see. The Answer to Life, the Universe, and Everything!

Sorry Dan, I'm having trouble working out what it's representing

I did a couple of port maps on paper for some popular cylinders, took a digital pic....fed pic into port-map program, it auto-traces the ports, feed in a few parameters (bore, stroke etc etc) and (amongst other things) it calcs the port-time-area graph shown. You can use the info to interpret power delivery, and if you make alts to your porting, you can use the info to predict what the alts will change in your power delivery.

Red bar is exhaust angle area and blue is transfer angle area.

Exhaust and Trans port timings and blowdown in degrees shown in top left corner.

Angle area on vertical axis, rpm on horizontal.

Additional Info:
http://www.macdizzy.com/cylinder_map5.htm

http://www.satis-factions.com/HPTSPORT/letflow.htm

So when i fed the maps in, i found the angle-area graph results interesting....i just wanted to see if any others on here have ventured down the road of port-time area, angle area.......to see how the port areas of exh and trans work together on certain kits, what info they had....and to compare resluts etc.

quite a while ago now dan.............i tried to broach the subject of BMEP............
but unfortunatly i think it was maybe a step too far..............for most..............even smiffy let me down.............
think it was somewhere at the end of the good old "long stroke/short stroke " topic.........