Three on the tree options

[dddDuster]

How important is a synchronized first gear?

So- I grew up close to the farm, working for my Aunts and Uncles, driving crappy old tractors and trucks. Later in life I drove trucks for about 10 years in the oil field. The key word here is “double clutch”. Learn how to do it and the 903 slides right into first gear, at least mine does. The 903 is a pretty crummy, weak transmission and I have plenty of issues with mine, mostly trying to keep it from leaking all the time, but the non-synchro first gear isn’t really one of them. In the grand scheme a 903 is a small issue, but it probably has a 7 1/4” diff behind it, you will have way more trouble over time with that IF you are trying to drive it aggressively. If you’re just cruising, it will be fine.

 

[MidnightSwinger]

Just picked up an a230 and the 7 1/4 is long gone. This should be a fun little combo!

 

[French demon]

How important is a synchronized first gear? I mean first gear is generally only a take off from a stop gear.

Yes.
I have a A230 gearbox and at slow speed, I often use the first gear as I would use the second gear with a 4-speed gearbox.
I don't know if I'm very clear, but the 1st gear is fortunately synchronized

 

[Dartnut]

Go with the 230, and don't look back.
I think the 230 is a floor shift only tranny, but in my experience, it is a good tranny and it was available on the 383 magnum in 1970 B-Bodies, so it has to be strong.
If it's good enough for a 340 in A-Bodies or a 383 magnum in B-Bodies, Chrysler had to be confident in their strength...

 

[French demon]

The A230 is strong... and very pleasant to use.
Mine is 53 y.o, no leak, never rebuilt and the gear shift is butter

Really a nice gearbox, if you want a 3-speed, go with it

 

[MidnightSwinger]

Go with the 230, and don't look back.
I think the 230 is a floor shift only tranny, but in my experience, it is a good tranny and it was available on the 383 magnum in 1970 B-Bodies, so it has to be strong.
If it's good enough for a 340 in A-Bodies or a 383 magnum in B-Bodies, Chrysler had to be confident in their strength...

They were column shift and floor shift. Apparently you have to do floor surgery either way in the early A, so I’m just gonna run the floor shifter.

 

[bcschief]

Being you have no transmission to start with I would go with the 230 but it will also require a driveshaft because 65 still has a ball and trunnion drive shaft. I am pretty sure that they came in column shift, but you may have to modify the shift rods, speedo cable would require being updated. Not sure on the driveshaft but a 66 Dart would be a place to start. A 65-66 slant six 4 speed bellhousing would work with the clutch bell crank parts from the original car.

 

[66 Valiant wagon]

I have a 903 in my 66 Valiant with a 225. I love it. No, it's not synchronized but I can throw it into 2nd going 5mph and its fine. And no, it doesn't have overdrive, but I have done 75mph for hours and the 225 just sings. Honestly having less gears to shift makes it very nice. I have a T5 behind a 302 in a Ford and I'm constantly shifting gears. I truly don't think the T5 is any different than the 903 on the highway. They both cruise nicely.

 

[RustyRatRod]

I have the A903 in Vixen and I can get it in 1st long before I roll to a stop with no grinding. Same with the T18 4 speed in my Ford truck. It's also non synchronized 1st gear. I guess it all depends on what you're used to. Now the truck I have to wait until I'm going a little slower than the Valiant, because it had a 3.73 rear gear and spins the transmission pretty good, but It gets in there still rolling.