Downdraft Head Conversions

A picture is worth a thousand words...

headrear.jpg (65894 bytes)     headtop.jpg (65151 bytes)    headbott.jpg (59714 bytes)    headside.jpg (50330 bytes)
* Keep in mind that this started as a single (horizontal) port Rotax head...

Flow increase is subjective depending upon a wide range of variables.
Suffice it to say that this particular head stacked on our short stroke 500
turned @ 11,000 rpm and gapped the field at Daytona '99 by 30 seconds
at the checkered flag. This same head on our "big bore" 81 mm stroke engine
(675cc) turns over 9,000 RPM...enough to win 2 MRA championships.
Wake your single up with a BBM downdraft head!