280z 5-speed into a 240?

[Garm]

Hi all, I'm new here. Just got a pretty clean 1973 240z.
The car has an L28/N47 280z motor and head in it, carbureted. Drives really nice.

My question is can I bolt in a 280z 5-speed?
Are any special parts needed at either the engine end or the shaft end?

What about the interior shifter box?

Guidance and experience are appreciated. Thanks.

Edited May 16, 2019 by Garm

[Dave WM]

I presume you want a 5 speed for better hiway speeds? if so the late years 280zx close ratio has a very tall OD .75, depending on the rear end that can make for a 5th that is use less until near 70mph. If you just want more gears and be able to use 5th you would want to make sure the final gear ration in the diff is more like a 3.7 or 3.9. So 1st thing you should find out is what kind of diff to you have? is it a 180 or 200 and what is the ratio. then you can better decide what your needs are as far as transmissions considering the end goal. The engine makes a lot of torque so lots of gears are not really needed to stay in the power band.

Edited May 16, 2019 by Dave WM

[Garm]

If I could have a 5th speed on top of my 4-speed that would be great, like an overdrive. I keep reaching for it! ?
I see your point about which diff, and I don't know what I have in there.

It's probably the stock 4-speed diff, given the history of the car. I read that you have to open the diff up to read the code inside?

I did find a some posts about this  or similar swaps, so I apologize if it's redundant material, but I found the posts to be a little contradictory (and up to ten years old!)

 

Edited May 16, 2019 by Garm

[Dave WM]

240 guy have to chime in on fitment, something may need to be trimmed to fit on the tunnel. Also getting the right shifter matters, On mine I used a ZX style and had to had an extender part to make it not sit so low. Also there maybe some issues on the drive shaft as far as the mounting flanges on the rear. I like my 81 IIRC ZX with a 3.54 has a .75 od so I can go 80 at 3k. But I don't even get in to it until 70.

It maybe a bit more complicated than its worth on a 240 imho (trimming/diff swap/driveshaft swap). on the 280 it was bolt on affair, do it in a day.

Also you "may" have to remove the exhaust down pipe for clearance, I did on my 280. that is a bit of a PITA if the bolts are rust welded to the manifold, I ended up breaking 2 of the 3 so off came the exhaust manifolds, replacing gaskets, fixing broken manifold bolts... just understand things can go wrong making more work. Is it all worth it, that's up to just how badly you want that OD.

[Dave WM]

if you want to go along for the ride on my adventures in swap on a 280

 

[Garm]

Understood, thanks. I am starting with a 280z motor in the car, I think that simplifies things. I've read a few places it's a straight bolt on, even re-using the 240 shifter. 

And no, I don't want weeks worth of downtime trying to figure out something or fabricate something; I'd rather be out driving it!

[siteunseen]

The lower geared r180 is square looking. Taller r200 is more rounded. I put a wide 5 speed with the oe r180 and really like it. 70 to 80 mph on the interstate is 2,000 to 2,500 rpms. That's the only time i use fifth. It's like having the oe 4 speed around town.

Great looking car btw. Glad you joined the forum. Lots of info and even more nice folks. Cliff

[Dave WM]

You need to figure out the rear end ratio 1st before deciding anything else. It can be figured by counting turns on the input to the output.

 

[Dave WM]

3 minutes ago, siteunseen said:

The lower geared r180 is square looking. Taller r200 is more rounded. I put a wide 5 speed with the oe r180 and really like it. 70 to 80 mph on the interstate is 2,000 to 2,500 rpms. That's the only time i use fifth. It's like having the oe 4 speed around town.

Great looking car btw. Glad you joined the forum. Lots of info and even more nice folks. Cliff

which 5 speed?

 

[Mike]

Welcome to the club.  Clean looking Z you picked up!

[siteunseen]

The B type from a 280Z.

[Garm]

@Mike thank you, great forum here. 

I am the 3rd owner, and I have receipts all the way back to the purchase of the car. Other than the wheels, I'm not going to get too crazy with this one. (I have other cars for that, lol).