What np205's are interchangeable

[Clubbs]

Gathering parts for the 440 swap into the cj. I've the engine and a torque flight 727 trans that's mounted to a 203 tcase.

The 203 is a unique input and trans adapter so I'm picking up a jeep 727 tomorrow that has the standard round pattern and 23 spline output shaft. I'll swap the shaft and adapter into my big block Mopar trans.

I was figuring on two scenarios: use the stock Dana 300 from the jeep since it will bolt right up, but it's so small I think the front driveshaft will hit the trans pan even though I'm running a full width Dana 60 front. So I was just going to use a dodge np205 instead.

I'm not sure but it looks like the dodge np205 has the same figure 8 input bolt pattern as the gm box. And if so it has an adapter to convert to the round 6 bolt pattern that will be on the trans. Is that true? How long is this going to be?

I have a gm 32 spline big bearing 205 case I was going to use as a doubler with my 203. That's a long package for a cj, but it may be close to the 727 adapter to adapter to 205 I'll have to run anyway.

Anyone got any pics of a dodge 727 with a dodge 205 bolted up? I don't think I can use my big bearing 32 spline input gm 205 even if I change the input shaft because the big bearing won't fit in the adapter. Any ideas or confirmation on either of those questions would be appreciated

 

[CLRracer]

I'm not sure but it looks like the dodge np205 has the same figure 8 input bolt pattern as the gm box. And if so it has an adapter to convert to the round 6 bolt pattern that will be on the trans. Is that true?

This is correct. I have one off the transmission I can get some measurements from later. According to ORD, a 203/205 doubler with their kit is the same length as a stock 203, which is a few inches (two I think?) longer than just the 205 and Dodge adapter. The adaptor *should* fit over the big bearing GM case because the diesel trucks with manual transmissions used a big bearing 29 spline input. Dodge 205's have a male splined input shaft and use a female splined coupler to mate to the transmission output shaft, so I don't know what input and adapter options could be used make a shorter package with the big bearing GM case. I know a CJ is short, but if the doubler will fit that's the route I would go. You have all the hard to find parts already.

Duane

 

[CLRracer]

This 205 is from a 93 CTD truck with the big bearing 29 spline input. Looks like right at 14in from the transmission mating surface to the output seal. The adaptor looks about 4in long.

Duane

 

[Clubbs]

This is super helpful. Thanks for taking the time to pull measurements. I'll measure the 203 adapter in the ramcharger and figure out what the stack up would be with a doubler.

I stretched the cj about 7" in the rear and the 440 is 2 cylinders shorter than the 258... Ok maybe that math doesn't exactly work. I've got some measuring to do. The other concern is fitting the exhaust down between the frame. Maybe that's not a big issue, but I don't think my long tube truck headers are going to work.

 

[CLRracer]

I didn't think the 203 has an adapter like the 205? I thought it just bolts to the transmission like a 208 or 241 would, it just has a different pattern so the trans tail housing is different. The adapter for the 205 would come off for the doubler, so it should be the range box for the 203 is (6in) plus how thick the doubler plate is plus the 205 minus the adapter (14in-4in). So somewhere around 18 or 19in, which is how big ORD says a stock 203 is in this tech article. As for exhaust, zoomies makes everything better

Duane

 

[Clubbs]

The T5 / Dana 300 in the jeep now is 34" long from bellhousing to center of rear ujoint. Apparently a 727 with 203/205 doubler is 48-1/2" long. That's a bit long. Although the ramcharger has nearly the same wheelbase on my stretched jeep so maybe it'll fit