65 small block 727 question...

. so i have a 65 D100 with a poly 318 and cable operated 727...

my question is, if i decide to drop a good running 360 into it will be a direct swap?

is the converter hub the same on a 65 as it is on the newer ones? i thought somewhere in the 60's the size changed.. if it is different is there anyway to put the newer motor up to the older trans/converter?

i'd just throw another 727 in it but i'd like to keep the dash mounted shifter...

I believe your going to want to pick up one of those balanced flex plates. Then you won't have to mess with the trans at all, other then bolting it to the motor.
I believe the converter change was between 67 & 68, so the 65 trans won't play well with a 360 converter. Gene

yea i have the flexplate..

Damn! thats what i thought.... wonder if i can convert the older trans to accept the newer converter?

Talk to a local shop about getting a custom TC made. I had one done for a 78 400 in front of a 64 727 years ago. You can get it with the 360 imbalance weights if needed.

hmmm.. good idea.. thanks

The 65 727 uses a 19 spline converter in the big block, I think same for small block. If so, they are hard to find and pretty limited availability unless you go custom or change the shaft to the later style.

Yes, it's done often. You need a later input shaft and reaction shaft support. In the long run it's the best way to go, avoids having to shop for an orphan converter.

I don't know about a 360, but the magnum 5.9 bolted on and ran just fine.
I used the b&m flex plate, that was designed to balance instead of adding weights to the conveter.

been running it for a while now.
There was 1 hole that didn't line up and the brace on one side wouldn't bolt up either. but most people seem to leave that off anyway.

ok cool.. o i have a few parts transmissions laying around so thats a great option..

the converter hub was the same size?

i'm not worried about the balance.. i have a b&m flex plate laying around already .

The slant six is the one with the conv. hub change that you are thinking of.

ok... so its just the spline count then?

If have a parts transmission you should change the input shaft assembly. That is what I am doing for a 65 BB tranny right now.

that's what I would do & then you could could use any later 727 converter & if it ain't a 360 (ext balanced) converter, you already have the B&M conversion flexplate in hand to match it to the ext balanced 360 eng.

I kept the 65 transmission and converter. But I might not understand what you are talking about.
it was behind a poly 318, and I just used the b&m flex plate. no issues for the last 7 or 8 years.

the combo you are using is perfectly ok, and you can expect no problems to arise. what the benefit of changing to the later model pump parts is when you are shopping for, or need a converter that is, or has very different characteristics than your stock 1965 converter. the early [65 & earlier] converters are hard to find and much more expensive in a performance, high stall speed, design than the later converters are, hence the pump changes to take advantage of the vastly different, superior, and much cheaper converter offerings. hope this clears up the understanding of the reason to swap to later parts.

And the early 273. (pre-'68)

The input shaft spline count changed around '66-67
I think you can install a later year input shaft in the trans and use the more common '67 and up torque converters. The 360 balance issue can be handled with the special B&M flexplate or a correctly counterbalanced torque converter. The older 360 and Magnum 360 used different counterbalance weights.

Call John Cope at Cope racing transmissions to verify compatibility.

I think (been awhile) that the 340/360 motor mount ears on the drivers side are about 1/2" further back (or forward) from the 318, and the drivers side boss for the lower engine to trans strut is forward a but requiring a spacer and longer bolt. I think on my truck I just ended up having one of the motor mounts turned sideways to make up the difference? That was back around 1980, so getting hard to remember.