Hello everyone...

was wondering if anyone could answer a couple questions for me..

I have a :
1966 Plymouth Valiant
225 slant 6

I am currently in the process of removing a 7.25 rear end and replacing with a 8.75 (Small Yoke) rearend.

I know that I have to shorten the drive shaft but is the Stock /6 drive shaft capable of handling higher horsepower or do I need a Larger V-8 driveshaft?

I am planning on upgrading the /6 with quite a bit more horsepower and installing a high stall conv. that is coming with the 904 trans.

also.. I am changing from three on the tree to an automatic.. The engine in the car is a mid 70's and the 904 that I am getting from a buddy is a 1966...the 904 has a custom high stall converter with a small nose. Question... is the input shaft on the trans different between a 1966 and mid 70's motor. I know that the flange hub on the crank is larger on the 70's engine but I just wasnt sure if this combo will work with the 1966 trans?

any advice is greatly appreciated.

Thanks in advance...
Hank

Sad to say that the trans input shaft and spline count is different.
Starting in 1968 the shaft / splines increased in size.
DD

thanks for the answer... Doctor Dodge..
is it possible to change the input shaft on the trans to the large spline to match my engine without to much labor? I would like to be able to use the trans and could always buy another torque converter..

Thanks
Hank

I'm not sure what you are trying to do. But as long as the torque converter has the small pilot for the crank, any combination of trans, and engine is possible.
67 older engine has small pilot, use converter as is.
68 newer engine has large pilot, use adapter ring, made on lathe, or available from Wildcat auto parts.
If converter has 67 older small spline, use early trans, or if you want the late trans, change the input shaft and front pump to the early one.
If converter has 68 newer large spline, use the late trans, or change the input shaft and front pump in the early trans to the late units.
Use the flex plate for the year of the engine.
PS if using the 1965 down trans, with the flange on the output, it is not possible to use the low first gear planitaries from a later trans.
If any of this is not clear just ask.

All of my converters have the small pilot and the large input spline. That way I can use the early engine as is, or the late engine with the adapter ring. The early trans, with a late front pump and input shaft, or a late trans as is.

_________________
Charrlie_S
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