New World Datsuns...

Wayno, your the man! That sounds very likely...
The fact that the bushing in the trans had came out a bit makes me think it was a combination of things..
The size driveline forsure could be something it seems. I mean your right about the 520 one piece... it's small..


I picked up a 4 speed from ted. Or tdaaj.. Also have a stock drive line. SO ill put that in and baby the shit out of it so I can get it to the meet I set up..
Also need to find out what I should do for a long term Transmission plan.. thinking ka trans l front case. So some mods to the case a be needed BUT! It's strong..

OK, I am not changing my opinion here, I do believe that it was driveline failure.

You get to use the same tranny mount weather it is a short or long shaft 5 speed, if you use the stock 4 speed, you will have to go back to the stock transmission mount, you still have it?
I think that the 720 5 speeds are plenty strong enough for the LZ23, as they are built for the Z24, and don't let anyone bullshit you, the Z24 has a lot of torque, and plenty of HP also, more than the LZ23, that is for sure.
If you have a bench seat, that is the best seat for a 521, you will not have more legroom with any other normal seat, bucket or bench, I would stay with a shortshaft 5 speed with the bench seat, if you have bucket seats, then go with the longshaft 5 speed, as they are everywhere.
Jeffs/icehouses tranny was the strong one, it still got destroyed when the driveline failed, so just because it's supposedly stronger and more expensive doesn't mean a thing when certain circumstances occur.
720 5 speeds are cheap and are ready to bolt in(shortshaft or L block Z car) as your case might be alright because the tailshaft took all the damage, but do look at it carefully, but I would use a 2 piece driveline next time.

My suspicion is directed at the driveline too. I run a 71B (620) 5-speed in my wagon have been beating the everlovin shit out of it for 3 years. My 2.4 is in the neighborhood of 170HP/TQ. It's held up fine.

I believe it was the drive line, the way you explained everything does make a lot of sense..
I'll see if I can get another trans like mine. The 720 shortshift. I was also thinking about this transmission , I mean it was behind a 2.4 and obviously that's got more power so I wasn't really thinking my lz is what did the damage that and I wasn't being hard on it, just a few times..

Will I use the same driveline? The stock two piece.

I cannot really tell you what mods are needed on a stock 521 driveline when going to a shortshaft 5 speed when using the stock driveline, you see I don't have even one stock 521 frame, the 521 work truck is on a 521 frame, but it has been stretched 2 feet, maybe only the yoke needs changed or a freeze plug needs installed in the 521 yoke, I know for sure it will need shortened if you use a longshaft, someone on here has done this and knows the answer, it's just not me.

uberkevin » Sun Nov 02, 2014 7:30 pm wrote:I believe it was the drive line, the way you explained everything does make a lot of sense..
I'll see if I can get another trans like mine. The 720 shortshift. I was also thinking about this transmission , I mean it was behind a 2.4 and obviously that's got more power so I wasn't really thinking my lz is what did the damage that and I wasn't being hard on it, just a few times..

Will I use the same driveline? The stock two piece.

It's all good I'm sure I'll find out what I need.
I'll get it done.

If the short 720 tranny is the same length as a dogleg....28.5 inches I think...then no mods are needed for your stock 2 piece 521 drive line.

IDK. Have always heard you have to use a dogleg, its the only one blah blah. But maybe that's just cuz the naps bell housing.

Anyone have confirmed information? Or was it posted and I just didn't read again

izzo » Mon Nov 03, 2014 10:37 am wrote:IDK. Have always heard you have to use a dogleg, its the only one blah blah. But maybe that's just cuz the naps bell housing.

Anyone have confirmed information? Or was it posted and I just didn't read again

I believe it's just the bell housing... Paging wayno.

There are factory short 5 speeds, non dogleg. Pretty sure the 620 got them, but its not common. FYI, short is 26 inches, long is 28.5, Hardbody 71C is 30.5, and S13 is 31.5.

I have a 620 drive line, its a 2 piece. It's a 74 standard cab short bed pickup. was mated to a 4 speed. So it's stock length and shit.

Your's free if you need it. I think the carrier bearing is good too. IDK tho. anyways, yours free. come and get it if you want it.

draker » Mon Nov 03, 2014 11:23 am wrote:

izzo » Mon Nov 03, 2014 10:37 am wrote:IDK. Have always heard you have to use a dogleg, its the only one blah blah. But maybe that's just cuz the naps bell housing.

Anyone have confirmed information? Or was it posted and I just didn't read again

I believe it's just the bell housing... Paging wayno.

I had an L16/dogleg in my 521 work truck when I bought it(normal truck before wayno), when I made my hybrid shortshaft 5 speed out of the late 720 shortshaft 5 speed transmission and the 1980 720 longshaft 4/5 speed front case, it bolted right in, that was because someone before me had already made the tranny mount conversion(slightly back and lower), and had already changed out the yoke also.
Before I figured out how to make the hybrid 5 speed, I always thought that the dogleg(77-79 200SX) was the only shortshaft 5 speed that would fit in a 521, but after I went threw 4 doglegs in 5 years, I started looking for alternatives.

did those come out of the standard cab 720s?

izzo » Mon Nov 03, 2014 3:05 pm wrote:did those come out of the standard cab 720s?

85-86 standard cab/short box 720s, there might be 84s with shortshafts also, I don't recall seeing any though.

I made mine as wayno did.. well kinda.. 620 4 speed front case on the short 720 trans... just need to change the bearing. I've heard a few things like I can use a 620 drive line so I'll grab that shit izzo! Tdaaj had said something about using the front portion of the 620 DL..

Like I said I'll make it work and get back on the road soon. Hoping by the weekend .
Check this out

Well... The bellhousing is still good...

How come everything is just periods on your thread over there?

I see it's bent(output shaft), but from what I can see, the gears look alright/intact back there, does anything you see make you think that the transmission was the issue?

Didn't know what say to flatcat, and banana being banana.

There's a few troblesum jarring in some spots where a bear rests.. Also some chunks of gears missing or chewed up.

I don't really see anything that points to the transmission..