Automatic Transmission swap for 510

[charlie6178]

i just pulled a complete auto out of my 1970 510 2dr. i personally never drove the car with the auto in it, but i drained the fluid and it was all clean, no shavings, dark colors, or burnt smell to talk about. i do not know if it is the original trans out of the car, the motor is an L20B, therefore i can not be 100% sure. but i am selling the transmisson, torque converter, flexplate, trans crossmember, and dust sheild. i am not selling the pledal assembly, or the factory shifter. but i will include all of the hardeware and the shift linkage.

 

i have dont know what to ask for all of this, so i'll let you guys make me offers....

 

i'm not going to give it away, but i also know it isn't a gold mine so MAKE ME SOME OFFERS!!!

[slodat]

I have thrown two of those away..

[RandyinRenton]

can you check the model number?

[charlie6178]

what numbers? and where are they located?

[datzenmike]

The '70 should look like this one except yours will have a shorter tail stock. You can see the model # 3N71B (made by JATCO)

 

http://www.showcargarage.com/gallery/files/1/DatsunEngineSwap001.jpg[/img]"]

 

One other tranny could have been swapped on though. The Borg Warner 35 from '68 (and maybe '69). The BW 35 had a down shift cable from the carb while the 3N71B was an electric switch at the gas pedal and a solenoid at the tranny. The shift linkage is on the driver's side on the BW and on the pass side on the JATCO. Both automatic trannys were the same 26.3" long in the older 510s. 620 truck automatics from '74 on were long tail at 31.5" like the one in the picture.

Edited October 27, 2008 by datzenmike

[qwik510]

Speaking of automatics from 510's, I am about to pull one from my 1970 2 door. It is a column shift. It works great and has 119K miles on it. It does not leak and shifts well. There is an emblem on the back of the car that reads "B/W Full Automatic"

 

If anyone is interested, let me know. If you hurry, you can come and drive it to feel how it shifts before you buy it.

 

BTW, I have heard that Racers use the flexplate to make a smaller, lightweight clutch/flywheel assembly.

 

P.S. Sorry to ride on the coat tails of your thread.

[Mark_Z28]

If the trans is the longer version Id like the trans crossmember for my 710, converting from 4 speed to ZX 5 speed and they are the same length as the longer auto transmissions.

[datzenmike]

The '70 should look like this one except yours will have a shorter tail stock.... One other tranny could have been swapped on though... The Borg Warner 35 from '68 (and maybe '69).... Both automatic trannys were the same 26.3" long in the older 510s. .

 

So, no it won't be a long tail automatic.

[Rubberman]

Now if this is off a L20 motor, is that the original motor. Will that trans fit in my 77 620? Anyone? Thanks?

[charlie6178]

okay so i checked it our today, it's def a car trans. it's just under 26 3/4".....

[Mark_Z28]

Poop, hoped it was the long version.

[freaky510]

hit up DaTsUn72WaG his trans just went out and his dad wont let/help him with a manual swap:(. HE could relly use a auto tranny.and if you talk to him before i do tell him i will help him pick it up:lol::lol:

[charlie6178]

yeah tell him to contact me, it should be cherry! it looks to be in very good shape, and the fluid was all good.... tell him to throw me and offer.

[mklotz70]

...hhhmmm.....I thought we were already working on a trade a week or two ago when we talked on the phone. What happened?

[datzenmike]

BTW, I have heard that Racers use the flexplate to make a smaller, lightweight clutch/flywheel assembly.

 

Urban legend. The auto flex plate is almost that! It's a bit thicker than a large 5gal paint can lid with a starter ring on it.

 

http://i138.photobucket.com/albums/q251/datzenmike/enginedriveplates78620and88D-21Larg.jpg[/img]"]

[qwik510]

Urban legend. The auto flex plate is almost that! It's a bit thicker than a large 5gal paint can lid with a starter ring on it.

 

http://i138.photobucket.com/albums/q251/datzenmike/enginedriveplates78620and88D-21Larg.jpg[/img]"]

 

It may be a legend to you but the guy I talked to told me that he has made several of them. He starts with the 510 automatic flexplate and uses the starter ring and welds a small 7" custom flywheel into it with several braces going out to the starter ring. He says it cuts down on weight and still allows the use of a stock starter.

 

I never saw one but it sure sounded like he knoew what he was talking about. seems to make sense too. Flywheels are heavy.

[datzenmike]

And they are heavy for a good reason. Motors don't make enough torque to get a couple of thousand pounds moving from a stand still. Best thing is a heavy flywheel that can be spun up to say 1,000 RPMs and store some energy for when the clutch is let out. The draw back is that once moving, some engine energy must always be used to spin up the flywheel with the engine revs. L20B typically run a 29 lb wheel and they work just fine. For a car you could go a little lighter. Too light and you will have difficult takeoffs with much clutch slipping and it will be easier to stall. If you drive on the streets in stop and go avoid very light flywheels. If you race where you seldom stop you hardly even need one, just a starter ring. An 8 lb racing flywheel will free up a couple of hp, but it's one of those things that doesn't translate over to a street car with good results. Better to get lighter alloy rims, tires, brake rotors maybe an aluminum drive shaft. Take 10 lbs of spinning mass off of those instead.

 

I have a stock 21 lb on my 620s Z24 but I figure the crank and rods are heavier than the L20B so it averages out. Works good on a 3,400 truck. Maybe just under 20 lb for a truck and 15 for a lighter car.

 

Here's a diagram of where to remove excess weight on an L flywheel:

 

http://i138.photobucket.com/albums/q251/datzenmike/transflywheel_spec.jpg[/img]"]

[Mark_Z28]

They make the multiple clutch kits for chevies to that look like an auto flexplate. They are used for racing where they dont have to take off, all high rpm stuff.