65/66 ST300 BOP pattern vs. Nailhead.

[dlmwtvl]

Okay, So the Dynaflow was done after 63.
The 64 ST transmissions were junk. (so I'm told)
In 65 and 66, the ST 300 was made in both, BOP, and Nailhead, patterns??
Were they the same transmission on the inside? Or, was the Nailhead patterened one, built with different internals to handle the torque of the Nailheads??
Also, was the ST 400 also made in both patterns, as well??
Also, does someone make a Nailhead adapter for the TH400, or the 700R4??
I saw one for the 4L60E, but I'm not interested in a computer controlled transmission.
Thank you.
David

[Dr Frankenbuick]

The Nailhead and small block 300s transmissions were not the same internally. A few of the things that are not the same: different line pressures, valve bodies, pistons, settings as well as differences in the number of clutches.

The ST400 was made in both the Nailhead and BOP patterns. It was variable pitch through 67, but as you know, the 64 was not variable pitch. The 64 ST400 is not a bad transmission, but is a stand alone year needing some finesse.

Adapters are available for most aftermarket BOP and even chevy pattern transmissions to the Nailhead engine.


Sent from my iPhone using Tapatalk

[WkillGS]

Bendtsens has adapters for a Chevy bellhousing to fit either the early or the late Nailheads. Kits are different depending on crankshaft:
http://transmissionadapters.com/53-66_nailhead.htm

Russ has an adapter for the 4L60E, dunno if the 4L80E differs. He also offers crank adapters:
http://nailheadbuick.com/transadaptors