67 impala...i know right

X a bunch but not ported because they run off full manifold vacuum, and if it smokes like a pig and won't shift the modulator is probably why.
When the diaphragm in it goes bad it lets trans fluid get sucked up into the intake.

67 is probably a 2 speed powerglide trans though unless it's been changed.

Sorry there Badsport, but it's true.

Hmmm, I just replaced the modulator on my wife's 73 Comet last Friday, it is hooked to ported, I thought. Now I have to go double check.:banghead:

I was thinking the same thing about the slushbox.