As cast they are bigger than a 906 but smaller than a true MW, about 1/2 way in between. If I had a TF 240 port matched to a 906 on a strong high compression 440 or a stroker motor I would still run it.

Plus you could always epoxy port match it if the mis match is too much to get a good seal. Id just Epoxy it deep into the runner roof and walls (the floor should be fine) to maintain a nice gradual taper.

The 337 works really nice, I was pleasantly surprised by the throttle response...even under load....and it's even better when ported, Hood clearance is a breeze on my Low deck with the Chapman Stage VI's

Larry Smith (RIP) did this one for me well over 10 years ago.