510 L16 w/ Automatic < L20b 280zx 5 speed swap ::Tutorial::

[TheBirdistheWord]

Im going to try and put some of the important swap info that I had to search around for and some personal input from my experience in one spot with this post, so bare with me if its a bit long winded or if any info seems obvious.

 

I had never performed a motor/trans swap in its entirety, and it only took me two weeks working on it two hours a night, outside, in the rain. I really believe anyone with a mechanical inclination and access to proper tools can do this with ease as well as relatively quickly. I was thinking about putting total cost as well, but I figure that cost of parts will vary a bit from location to location and as time goes on.

 

I started with:

Rebuilt L20b short block w/ oil pump

used 280zx 5 speed manual (uses a shorter drive shaft, I believe if you use a 4 speed or dogleg 5 speed you dont have to change the driveshaft)

ebay trans swap cross member

pedal box from a manual 510

reman 510 clutch master cylinder

reman 280zx clutch slave cylinder

hard clutch line from a manual 510 ( I would use custom bent lines if I were to do it over)

soft slave cylinder clutch line (connects slave cylinder to hard line from master cylinder)

used short driveshaft (only for 280zx and 620 5 speeds)

resurfaced 6 bolt 200mm flywheel (other sized flywheels can be used they just need to be a 6 bolt mount for the L20b and matched with the same size clutch)

new OEM flywheel bolts

new pressure plate alignment dowels

new 200mm clutch and pressure plate

new throwout bearing for 200mm clutch

new throwout bearing sleeve/collar for 200mm clutch

AND my barely running 510 with a L16 and 3 speed auto.

 

::Note:: I wanted to use the roadster clutch because I had read hear on ratsun about its durability. However, I had alot of trouble sourcing a 6 bolt 200mm flywheel locally, so I would recommend picking up any size 6 bolt flywheel you come across and get the same size clutch parts. Unless you plan on racing or beating the crap out of it.

 

I pulled the L16 and auto from the car first. DRAIN ALL FLUIDS or it will get damn messy, ask me how I know. :blush:

Take pictures and or label EVERYTHING before you disassemble. Remove all the obvious wires, hoses, and cables attached to the motor that are coming from the firewall and fenders. Remove radiator for clearance, I recommend removing the hood and steering center link as well, although I didnt it was a very tight squeeze. Be sure to remove the bracket on the trans tunnel that holds the auto shifter in place, disconnect tranny cooler lines, speedo cable, and transmission wires. Remove drive shaft to diff bolts, tranny crossmember bolts, motor mounts and everything should come right out.

 

::Note:: I cut the exhaust at the bend close the floor pan, although ive read about people just bending or "dinging" the exhaust to compensate for the L20b being 3/4 of an inch taller, I wasnt comfortable with the clearance I was getting with either of those methods so I brought it to an exhaust shop after I got it running.

 

I literally installed EVERYTHING from the L16 onto the L20b. Oil pan w/pickup, valve cover,intake manifold w/carb, exhaust manifold, electronic ignition, water pump, starter, alternator w/ bracket, fuel pump, and although I didnt use the oil pump or crank pulley from the L16 im ALMOST positive they are the same parts. The lower thermostat housing breaks very easily as mine did upon removal so I would recommend getting a new one while its off, as well as housing to block gasket and thermostat cover gasket even if they look "fine" its a whole lot easier now when there isnt coolant dribbling through them.............. again, ask me how I know. :console:

 

::Note:: Some people delete the coolant bypass from the lower radiator to block fitting to the thermostat housing, I reconnected mine and have way more consistent temp readings. Also, the alternator bracket to block holes were larger on the L20b, dont remember what size mine were I actually just ended up using some standard bolts I had lying around and drilling out the bracket.

 

Installing the flywheel and clutch is pretty straight forward once you have all the parts in front of you, just remember to check, and double check torque settings. You'll need the alignment dowels and clutch alignment tool. The auto mounting bolts are not long enough to mount the zx trans to the L20b so I sourced some at the local hardware store. Remember to install correct throwout bearing and collar/sleeve in trans before mating it up to the motor. Aslo, the zx trans clutch fork appears to have worked, and it appears to be another universal part. I will verify this when I replace the throwout bearing collar, I used the wrong one so my clutch is not engaging properly.

 

Installation is the reverse process of taking the L16 out. HOWEVER, You need to find 1/4 inch spacers to put in between the auto cross member and body to keep the drive shaft straight, and it needs to be flipped and modified to accept the manual. Although I got the trans installed, I couldnt find any combination of mounts or flipping that I was comfortable with so I ordered a swap cross member from ebay. Before attempting to bolt up the motor mounts take the entire mount assembly and loosely attach it to the motor so you have some play to line them up........ took me a while to figure that one out.

 

When I went to do my pedals I couldnt find any straight forward way to get the entire auto pedal box out and manual pedal box in without taking the entire dash frame out. The auto pedal box has the all of the necessary provisions for the manual pedal except for the pedal return spring mount on the drivers side of the pedal box. So, I cut it off of the manual pedal box, drilled and bolted it onto the auto pedal box and it works great. Connect soft slave line to hard master line and bleed system until you have pressure.

 

Assuming you took pictures and or labeled everything, it should all go back together pretty easy from this point on. the wiring harness that went to the old auto trans is going to have two black wires with a yellow stripe on them. They are for the park/neutral safety switch and need to be bridged for the car to start since you dont have a "park" anymore. You will need to adjust the carb(s) for the L20b, and with help from ratsun I adjusted the valve clearance at the same time.

 

err... I think thats everything. I know that this information in one place would have helped alot in the search for information about this swap.

 

I should have taken pictures!!! I still might when I go to install the cross member and throw out bearing collar.

 

any other input is welcome! better to have the bulk of the info in one thread....

[jefe de jefes]

Thanks for sharing

[Guest kamakazi620]

Thanks for sharing

For sharing "What"???? All i heard was Blah Blah blah NO oics!!!!! and saw Nothing

[datzenmike]

Pilot bushing.... I guess the L20B was previously a standard?