As far as a nice cruise RPM both the PGlide and TH350 are 1:1 in high gear
so nothing is gained there. The TH350 however has a lower ratio in First
than the Glide does in Low so acceleration is better.
The simplest engine swap for decent performance and good cruising would be
the GM Perfomance 330hp crate engine. Being a small block 350 inch engine
it is a direct bolt in swap to replace the 327. For extended highway
cruising a TH700R4 or the newer electronic version both have the overdrive
feature for lower highway RPM. Either of these is longer than the Glide so
the driveshaft has to be shortened and the tranny crossmember moved about 2
to 2.5 inches further back.
Unless the 10 bolt needs major work it will be fine for a cruiser with a
mild small block
You might hang onto that 327 particularly if it is a 300 hp job, the 300 hp
and up all had steel cranks and were basically the Corvette engines but
stamped for the body model they were installed in, and are highly sought by
those who love the 327.
Just some thoughts......
"Opportunities are spawned from crisis"
I just picked up a '65 Impala SS.. It currently has a 327 with [i believe]
a 2-speed powerclunk transmission (console says PRNDL).. My friend is
looking at getting the car from me and making it a project/weekend driver
with some pin-you-in-the-seat power.
Question is... what would be the best engine/tranny combo for this car.
I'm going to yank the 327 as it's worn out, i'm sure (haven't started it but
prev. owner says 'it just needs a carb to run,' but was sitting at least 10
years with no air cleaner judging from the old stickers on the car). Might
as well do away with the 2-speed as i'm sure he would like to cruise on the
highway at a reasonable RPM. If I was keeping the car for myself, I would
probably leave the 327 and the powerglide but since it's for someone else..
Maybe a 350 with a TH350 behind it? Are there any pitfalls when
selecting an engine for this car? The car has a 10-bolt rear right now. I
haven't really looked at it much beyond that..
Thanks in advance.