L4N71B Transmission into Early 10-Series Car

[zerow]

Who will save this thread...?

 

datzenmike...where are you (sung to the Scooby Doo theme...)

[ggzilla]

That is a B110 drivetrain photo. Here's the other side

 

Here's what little info I have on the 4N71B swap: L4N71B Swap

 

* HL510 is a 1972 LHD 510 with L18 engine. Never sold in america.

* 1978-1981 510 is model series A10, which is badged as violet or stanza in other countries. Datsun Competition called it HL510, but no other Nissan literature refers to it as such.

[ggzilla]

Transmission mount in the photo is this one:

 

Older style:

 

Newer Style:

[zerow]

That is a B110 drivetrain photo. Here's the other side

 

Here's what little info I have on the 4N71B swap: L4N71B Swap

 

* HL510 is a 1972 LHD 510 with L18 engine. Never sold in america.

* 1978-1981 510 is model series A10, which is badged as violet or stanza in other countries. Datsun Competition called it HL510, but no other Nissan literature refers to it as such.

This fascinates me to no end...my bellhousing does not have an air cooler vent!

[MicroMachinery]

I have vent on my 3 speed auto that came in a 510.. but I'm not sure about the one that came in my 610..

[ggzilla]

They switched from air cooling to the traditional water cooling (tubes to the radiator) in 1974. You can see in the photo that their is a cooler line, the early ones just didn't use a cooler.

[zerow]

The L4N71B transmission is in!!! A finale to this addition to my 610. This upgrade has been HELL on my mind (and pocketbook), and as a good Sergeant, I will give everyone who is interested an "After Action Review" or AAR, based on this mission:

 

Report on Installation of L4N71B transmission into candidate 1973 Datsun 610 sedan (coupe models are very similar)

 

Success of Mission? Positive.

 

Moments of FUBAR? Affirmative.

 

Care to Elaborate? Affirmative. Original mounting will not work between the 3N71B and the L4N71B. A machined adaptor and spacers are REQUIRED!

When purchasing the L4N71B transmission candidate for possible swap, take EVERYTHING associated with the transmission. You will want the Flexplate, Bolts (just in case), Spacer between the flexplate and end of crankshaft, Fluid cooling lines with clamps and attachments, downshift vacuum hardline, Speedometer Cable, Linkage, Harness with at least 30 inches of wire (no need for the connector), Driveline (especially one from a Maxima coupe, as it is one piece, and did not require any lengthening or shortening to engage the differential)(Because, Nissan never made a one piece driveline for the Maxima, and you will need one custom fabricated with the ends for your particular application...edited 17 April 2012), nuts, bolts, EVERYTHING!!! Leave no wounded behind, take all prisoners...

 

 

Can you use the original rear mount from the 3N71B for the L4N71B? Affirmative. However, it requires an adaptor.

 

 

Did you have a new rear crossmember fabricated? Negative.

 

Please describe the adaptor mentioned above. The adaptor is steel, and as you can see, the inner holes are for utilizing the rear tailstock ears for mounting. You will use the original toggle bolts for mounting the steel adaptor plate to the transmission FIRST. The counterbored holes are for allowance of split lock washers and nuts. The counterbore is precise for the sockets that I was using (I suggest verification prior to fabrication of adaptor). The fit was perfect - no additional modifications required.

The outer holes are for the original stock saddle mount. Once again, utilize proper hardware with lock washers and nuts. For the sake of keeping this portion of the car "original", I utilized all metric fasteners for the mount, adaptor, and toggle bolts (stock from previous transmission)(Nissan)

Where can one obtain this adaptor? The shop drawings can be made available upon request. Please give credit where credit is due. zerow drew the plans for said adaptor, and datrod completed the finish product.

 

Are there any additional requirements for install? Affirmative. There is a required space needed to keep the driveshaft level. This mission required a minimum of 1 inch space from the bottom of the floorboard. In the installed photos, you will see the 1 inch milled aluminum spacers at the left and right sides of the mount. In addition to the spacers, I placed 1/8 inch rubber insulators to dampen any noise(s) between the spacer and the underside of the car.

 

On the interior side of the car, I had 1/4 inch thick plate stock, three inches wide and six inches long to provide extra support for the holes drilled into the floorboard. The locations proved to be a near perfect fit, as it did not interfere with the pressed countour of the floorboard. I drilled the holes to accept (minimum) 3/8" X 3 1/2" Grade 8 Carriage Bolts. The carriage head allows for minimal protrusion through the floorboard and less potential damage to carpet or other interior finish(es).

 

Any other installation notes? Affirmative:

1) Install all new seals on the rear of the motor, front of transmission, and rear of transmission. No need to do this twice.

2) Install the linkage PRIOR to installing the transmission into the tunnel. Reports from the front indicate time wasted attempting to install the linkage after the fact.

3) Install the fluid cooler lines AFTER transmission installation and settling, to ensure proper alignment.

4) Verify all parts are obtained and secured for installation.

5) Have a second set of hands. This transmission is extremely heavy, and can get out of control in a hurry if you do not have assistance.

 

Special Thanks to datrod and his exemplary machine shop services. This has been a heck of a mission making a transmission from a 10 year newer car fit into an older Datsun. I am happy to have taken this on and blazed the trail. Thanks to sublimedatsun610, wicked jester, stilltwisted, and 260zkaboom for their assistance in this install. Without the help and manpower of these guys, this would still be a mockup inside a garage.

Questions can be referred to me directly through this thread and are welcomed.

/End Report/

[datzenmike]

Excellent, informative and trail blazing work!!! Awesome pictures and commentary. I know many don't care for the auto but some do and others have little choice. Nice to see the 3N71B/L4N71B represented!

[ggzilla]

Excellent writeup.

[MicroMachinery]

Great stuff here, +10.

[broncosfan1]

Thanks to everyone that contributed to this post and the great summary by zerow at the end. Good stuff!!!

 

I'm interested in doing this auto trans with OD upgrade to my 74 3 speed auto 620 so I'm curious how well the L4N71B trans performs in the 73 610. I believe the 83 Maxima had the L24 engine with a lot more power so I'm wondering if my L18 will be able to take advantage of the OD.

[zerow]

Thanks to everyone that contributed to this post and the great summary by zerow at the end. Good stuff!!!

 

I'm interested in doing this auto trans with OD upgrade to my 74 3 speed auto 620 so I'm curious how well the L4N71B trans performs in the 73 610. I believe the 83 Maxima had the L24 engine with a lot more power so I'm wondering if my L18 will be able to take advantage of the OD.

broncosfan1 - your greatest hurdle to overcome will be getting a 5 bolt flexplate that works with the larger torque converter. If you look at the photo above, the flexplate is "dished" to accept the larger T.C., versus the flattened flexplate you will have from the three speed.

 

How well does the L4N71B perform in the 610? I have 3.70s out back, and an L20B. I love it. A little fast on the 1st gear shift, but great through the rest of the gears. The L20B has torque generated at lower RPMs than the L18, so I think that adds a big factor to this equation as well.

[broncosfan1]

broncosfan1 - your greatest hurdle to overcome will be getting a 5 bolt flexplate that works with the larger torque converter. If you look at the photo above, the flexplate is "dished" to accept the larger T.C., versus the flattened flexplate you will have from the three speed.

 

How well does the L4N71B perform in the 610? I have 3.0s out back, and an L20B. I love it. A little fast on the 1st gear shift, but great through the rest of the gears. The L20B has torque generated at lower RPMs than the L18, so I think that adds a big factor to this equation as well.

 

Zerow - thanks for the reply. I understand that I want the flex plate, torque converter, spacers, and drive shaft as well as the OD transmission from a 83/84 Maxima but have I missed something about 5 vs. 6 bolt flex plate? The one shown above has 6 bolts and I thought my L18 setup would match the L20B.

 

Glad to hear you are getting good performance from the L20B and this trans. My L18 is due for a rebuild so I was considering a L20B upgrade so that's another factor to consider. The rear end is my other concern but I don't know enough about that part to know how big an issue it is. If my diff is stock for 74 auto trans then it is H190 with 4.625 gears. From what I have gathered so far I would want a lower gear ratio with the proposed setup.

[zerow]

Zerow - thanks for the reply. I understand that I want the flex plate, torque converter, spacers, and drive shaft as well as the OD transmission from a 83/84 Maxima but have I missed something about 5 vs. 6 bolt flex plate? The one shown above has 6 bolts and I thought my L18 setup would match the L20B.

 

Glad to hear you are getting good performance from the L20B and this trans. My L18 is due for a rebuild so I was considering a L20B upgrade so that's another factor to consider. The rear end is my other concern but I don't know enough about that part to know how big an issue it is. If my diff is stock for 74 auto trans then it is H190 with 4.625 gears. From what I have gathered so far I would want a lower gear ratio with the proposed setup.

The L16 and L18 have 5 bolt flexplates, hence the reason I mention it (the L20B has a 6 bolt flexplate) If you are planning for the L20B upgrade, I say this would be the right reason to go forward with that decision.

 

As for a rear end swap, datzenmike would be the authority on what straight axles to look for, and what ratios are available. I am running 3.70s out back. A little slow on the draw, but once it gets going...zoooom!

[datzenmike]

You would have to carefully cut out the 5 bolt section and weld it into the L4N71B flex plate for it to fit the L16/18 5 bolt motors. No reason this would not work if done carefully.

 

Zerow, my 74 710 is an L18 auto and yes it gets into 2nd very fast.... about two car lengths. It you want to wind it out in first you have to mash it to the floor very soon on the take off. You hardly even notice the shift into 2nd and it's easy to assume 2nd is first and 3rd is second and you keep waiting for the shift that never comes. (not explaining very well but it just revs and revs)

[zerow]

You would have to carefully cut out the 5 bolt section and weld it into the L4N71B flex plate for it to fit the L16/18 5 bolt motors. No reason this would not work if done carefully.

 

Zerow, my 74 710 is an L18 auto and yes it gets into 2nd very fast.... about two car lengths. It you want to wind it out in first you have to mash it to the floor very soon on the take off. You hardly even notice the shift into 2nd and it's easy to assume 2nd is first and 3rd is second and you keep waiting for the shift that never comes. (not explaining very well but it just revs and revs)

Datzenmike - are you running the 3 speed auto? I understand the long rev theory. On the street, my 3rd to 4th (overdrive) is a bit on the "long winded" side. I still love watching the factory tach drop like a lead weight when I get into 4th :P

[datzenmike]

Yes 3 speed 3N71B and 4.11s. . If you just drive it away from a stop it goes into 2nd in about 2 car lengths, more like 1 1/2 lengths. You hardly even feel it. Second gear to 20? Third seems to rev and rev and rev and sure feels like there's going to be another shift but there isn't. :) Take getting used to. Had it to 90 two years ago coming back from Canby. Wow it was really screaming. I worked out the RPMs to 5200 not counting any tranny slip.

[zerow]

Well folks, I was wrong on part of this writeup. There is no such animal as a single piece driveline from a Maxima, the one I found at the junkyard was actually fabricated and fit perfectly for my 610. What are the odds of finding a 4 speed Maxima with a correct length single piece driveline already made for another application? I couldn't tell you. So, many apologies for anyone who has been hunting for the (now rarer than rocking horse crap) single piece driveline for a Maxima...they apparently do not exist.

[MicroMachinery]

I got one.. does that mean mine was custom fabricated too? :huh:

[zerow]

I got one.. does that mean mine was custom fabricated too? :huh:

You've got it. And now, that makes two...

[ghammer]

Hey everybody, i'm going to shoehorn a L4N71B into my 620 with a L20, in place of the original 3N71B. I've already gotten my trans and associated parts from PNP. My donor vehicle was a '84 Maxima. The only difference I found was it did not utilize a spacer between the flexplate and crank of the L24 in the car. Was that spacer only specific on the '83? Can anyone help with explaining the wiring of the overdrive solenoid? I am guessing the kickdown solenoid, reverse light/nuetral safety will all wire in the same as the original trans? Thanks in advance!

[datzenmike]

That's odd I was sure there was a spacer on the '84 Maxima that I took mine out of? Maybe not?

 

Kick down/rev/interlock looks the same.

to the transmission effect unless the wire to the ON/OFF switch is in the OFF position and is grounded.

 

I believe the OFF position on the switch grounds the wire going to the transmission. So it the switch on the shifter is left unplugged it will 'automatically' shift into 4th.

 

This is from an L4N71B from a D21 Hardbody. Looks like there is automatic transmission control unit? Like an ECU???? for the transmission for this. I don't remember the Maxima having this stuff.

[darrel]

All autos, z, maxima, etc had the spacer on the back of the crank. It covers the end of the crank and looks like it doesn't have a spacer. It is there.

 

The maximas till '84 all had the dumb transmissions. The later E trans had the control unit.

 

Without power, the OD will kick in. With power OD is off. I used a shift lever from a '88 maxima. I had to cut it down and drill for the set screws as well as cut the shift plate square so the shift lever would fit.

[datzenmike]

Fraid of that. Do you know where the control unit is located? Under seat???

[darrel]

Didn't someone put an E transmission put one in their datto in here? Wired the control unit, maybe with a KA engine? I'm sure it's in a build thread.