My Datsun 280zx Turbo Engine Swap
How
to put a turbo engine in your non turbo 280zx.
Note: This is a re-do of a page I made about a year ago. Unfortunately, my web host erased the whole page. Stupidly, I had not backed up the site after my computer crashed, so I lost some data. I still had most of the pics and will include them. I have also edited the page to be more clear and concise. I hope you find it useful.
Reasons For The Swap
First I will give you a
little history about me and my 1981 280zx. I have owned this car
since around 1996. The car was a hand-me-down from my sister when she
traded up to a Honda Civic. The old z-car had become much too
unreliable for her and she was unable (or unwilling) to fix it
herself any longer. The old beast frustrated her because it was very
temperamental in its starting habits and finally she had enough. I
gladly accepted the car, being a high school senior, it seemed pretty
cool to me. The car had previously belonged to my grandfather as he
bought it around 1989 or so. So I knew the history of the car, and
new it had been fairly well taken care of. Of course it did have some
kinks to work out of it. The car got me through college, but I had
always wanted to do a turbo swap, when I got out. I had tried doing
the typical mods to get the n/a engine to have more power. The small
stock exhaust was traded out for a 2.5" setup, and this seemed
to help some. The air intake was then "upgraded" with a
"cold air" cone filter. This mod did absolutely nothing. I
decided that getting this old anemic beast to move would require
something more substantial than minor bolt-ons. What it needed was
the famous L28ET out of a 1981-1983 280zx turbo!
Finding a
Turbo Engine
I had been casually looking for a turbo engine,
or whole donor car for a long time, rarely finding anything in my
area. Once I got out of college, I didn't have a job or anything to
do, so I had plenty of time to search. Eventually I found a whole
wrecked donor car in Sisters, Oregon which was about 150 miles away.
The car was severely damaged in the front and had been sitting for 10
years. The owner sent me pics and all and the engine looked largely
undamaged. I finally decided to buy it and settled on a price with
the guy over the phone. The price was 600 bucks which was a gamble as
I didn't know if the engine would really be any good. Fortunately it
was!! Luckily I was able to convince my Dad to help me go down and
get it. Dad's are always good for that! My Brother In Law reluctantly
let me borrow his "new" F-250. So with the F-250 and a
trailer borrowed from a friend, we went down to get the car!! I
couldn't believe I was finally going to get a hold of a real turbo
engine!!
Fortunately this car was wrecked and unrepairable. I
did not want to destroy some perfectly functional shaggy 280zx turbo as
many people have done. Some people don't have a problem with this as
many believe the 280zx to be a big pile of junk, but I beg to differ.
Some day there will be no zx-turbos left as everyone will have stolen
their engines to put in their presumably more "valuable"
260z's or 280z's. Well I bet a real 280zx turbo might fetch a good
price in the not so distant future, as few will be around!! Anyhow
that is my take on it.
Removing Turbo Engine
This
part was the first big hurdle. First we had to get the car off the
trailer, which was not easy. The front had been damaged bad enough
that the car could not roll on its own. Here's some pics of us
removing the car. Click on pics for bigger view!
As can be seen, the engine was pushed way over to the passenger
side of the car. Because of this, I feared that it could have some
serious damage. Fortunately, it didn't.
The only way to remove
the engine was to cut it out with a torch. First I removed as much of
the stuff in the engine compartment as I could reach. Some stuff had
to stay for now as it was pinched off or otherwise unaccessible Well
I didn't have a torch, so I had to go and buy one. An acetylene torch
is a good thing to have anyhow. My Dad did most of the cutting on the
car, being that he was much more experienced. After we got the front
of the car cut open, I could finally put a wrench on the engine to
see if it turned. I was very nervous that it wouldn't. Fortunately it
did, and I was greatly relieved. The next thing to do was remove all
of the parts that I could off the engine and label everything. This
is especially important for the fuel injection wiring harness. I
didn't even know what some of the stuff was at the time, so I just
made up some name for it, like "vacuum thingy" or something
like that. The FI harness is quite easy to remove and is totally
separate from the main harness. Basically there are a bunch of wires
that go to the manifold and left side of the car, and then there are
a few wires that are routed along the top of the firewall over to the
battery area. Behind the battery is a hole in the fender structural
area that contains the FI relay and a plug that connects to the main
harness. More detail will be provided on the wiring during the
install section.
Once the car was cut up, the engine could be
removed. I could reach all of the engine mounts and was able to
unbolt them. The engine mounts are fairly simple on the old z-cars.
There are two mounts, one on each side of the engine block, and
another mount back at the transmission. You only need to remove about
7 bolts for the engine to come out. It is pretty straight foreword.
You must remove the drive line first though. This is not hard either
and is self explanatory, but a little bit tedious. You need to either
cut the exhaust out or un bolt it. Then you need to take off the heat
shield. Finally you have access to the drive shaft. It comes off
pretty easy and slides out the rear of the tranny. I suggest draining
the tranny first, or else you will make a big mess like I did. Here
are some more pics of the engine removal:
Engine Preparation
My donor car had 100,000+ miles
on it, which is a lot, but not huge for the L28. I really didn't want
to do a full tear down of the engine, as I had no experience with
that. If I was smart I would have done at least a compression test
before tearing the tranny off. It wouldn't have been that hard to do.
Being inexperienced and assuming that the engine was in good shape, I
decided to just tear it apart and see. I wasn't even going to take
the head off, but when I got the manifolds off I could see a lot of
buildup on the valves. This made me think something could be worn on
the valve seats or whatever. Well I decided to take the head off and
get it rebuilt. This was not that hard, but I could not have done it
with out my Haynes manual and the book, How to Rebuild Your
Nissan/Datsun OHC Engine. I am sure that most z-car people are
familiar with these books. If not, go to Amazon.com and buy them now
as you will need them!! Luckily, when I got the head off the engine
looked pretty good. There was some carbon buildup on the cylinders,
but the cylinder walls looked good. Doing the top end overhaul of the
engine took some time. I started working on it around April or so and
didn't really get finished till around September of 2002. This was
only working in my spare time and on weekends though. This is also
the most major engine work I have ever done, so things take longer
when you are a novice.
In preparing your engine, don't get
too impatient. This will only lead to more trouble later. Take your
time and replace as many parts as you can afford. Here is a small
list of things I replaced.
Water Pump (Mine was damaged in wreck)
Oil Pump (Also damaged from wreck)
Hoses
Belts
Filters
Clutch (Don't forget pilot bushing and release bearing)
Another thing to get is a gasket kit. Felpro makes them for the L-series sixes, and I think Mr. Gasket too. Buy some gasket sealer and high temp silicon to seal all the gaskets (some don't require sealer(ie head gasket), so see the manuals). NAPA carries a lot of good brush on gasket sealers. Basically, just follow the How to Rebuild Your Nissan/Datsun OHC Engine book. It has everything you need to know about assembling the engine. Here are a couple of low-quality pics of my engine during the preparation process. The blue paint is New Ford Blue or something like that. This is the darker Ford engine paint. It is kind of similar to the original paint:
Installation
The physical installation of
the engine wasn't all that hard. I got new front and rear motor
mounts, just for good measure as my old ones had about 200k+ miles on
them. If you don't have a cherry picker or similar contraption,
then I recommend you get one or steal one from a friend. Don't use
the barn rafters down on the farm, or an old tree branch. The L28 is
quite the heavy engine. I won't go into too many details about the
physical installation. Just be careful and patient. Getting the front
motor mounts to line up is a royal pain. Get some big screwdrivers to
use as levers, and maybe even a 2x4 or two to work the engine around
to just the right position. Here are some pics of the engine
installation:
Wiring
Wiring the turbo EFI (or ECCS as Nissan
calls it) harness into a non-turbo zx is not all that complicated. It
seems like a daunting task, but is not that bad if you are properly
prepared. You would have a really hard time doing the wiring without
wiring diagrams. I used the Haynes manual which comes with copied
Nissan wiring diagrams. Unfortunately they didn't provide them in
color so they are hard to follow. Since then, I have found some
Nissan wiring diagrams that show the fuel harnesses and what they
connect to. I have links to them below. They show everything you need
to wire in the new harness. I also have a link to a schematic I drew
from the Haynes manual. This schematic shows which wires from the
eccs harness need to be hooked up to the main harness. Most can be
connected through their counterparts on the n/a efi harness. Some,
like the ignition switch, and igniter, need to be routed manually.
Also note that this is for hooking up an 83 turbo to an 81 non-turbo.
Differences may exist between the years, but should be similar.
My
EFI/ECCS Schematic
EFI
Circuit Diagram
EFI Wiring
Diagram
ECCS Circuit
Diagram (turbo)
ECCS Wiring
Diagram (turbo)
Please feel free to email me if you have any questions!
Other Issues and Comments
Steering
One thing that I wish I did when I had the engine out was to convert to rack and pinion power steering. All 1979-81 non-turbo cars (turbo first came out in 81) that had power steering had a recirculating ball type power steering (I think that's what it is called anyhow). Unfortunately, the gearbox for this type of steering is extremely close to where the turbo needs to go. I got my turbo to fit, but only after hacking the waste-gate actuator mount to make it clear the steering box. The gearbox is uncomfortably close to the turbo. You can see how close it is in this picture (sorry about the camera strap!):
As you can see the waste-gate and turbo itself are very close to the gearbox. I have not had any problems with this situation, but I also intend to swap out my steering to rack and pinion power steering from a later model 280zx. This would have been much easier to do while the engine was out as you need to replace the entire cross member that the engine is mounted on. All 1982-83 280zx's (turbo and non-turbo) had power rack and pinion, or manual rack and pinion steering (most probably were power). You should be able to find a setup in the junkyard. I do not know the details for the swap, but it should be straight-forward. I do not think that the steering column must also be replaced, but I could be wrong.
Hood
The hood on the 79-81 non turbo cars is different from that on the 81 turbo and all 82-83 zx's. The earlier hood has simple vents on it to help cool the engine (mostly after it has stopped, I think). The later model hood actually has an NACA style scoop on the turbo side of the engine. This scoop should help significantly with cooling. I have the older style hood that came on my car and have not yet run into any heat problems from the turbo, but if I ever find a good deal on a later model hood, I will replace mine.
Exhaust
If you do a turbo swap, you are going to need to get a new exhaust system as the stock exhaust will not bolt up to the turbo and probably is too small anyhow. The easiest thing to do is to take your car to a local shop and have them custom fabricate an exhaust for you. You can drive the car in with only the downpipe on the turbo without much problem. It is not as loud as you would think. My local shop guy did a very good job on my exhaust. It is 3” all the way from the downpipe back. I have a high flow catalytic converter and no muffler. It is really not all that loud as the turbo and cat do muffle the exhaust quite a bit. There is some droning at speed though, so I might put a high performance muffler on someday. You do not really need a mandrel bent exhaust. As long as you go over-sized with 3”, it should provide enough flow. A mandrel bent piece is almost necessary for the bend right after the downpipe. This is due to the tightness of the bend. A good technician should be able to fabricate a system within a few hours and for a couple hundred bucks or so. On the earlier zx's like mine, the exhaust needlessly exits on the right hand side of the car. Bending 3” pipe for those last 2 right angles would be very hard and unnecessary. I had my shop cut a notch in the rear valance and make the exhaust exit on the left as it did on all the turbo cars and later zx's.
Transmission
You have several options for the transmission. Probably you will want to go with a manual tranny. There were 3 manual trannys available on 280zx's. They will all fit on any z-car from 70-83. All the manual turbo cars came with a borg-warner T-5 tranny similar, but not the same, as the ones found on mustangs and other cars. This was different than the n/a cars which came with Nissan transmissions. Different trannys were made from 79-80 as from 81-83. I have the later model tranny which is usually preferred due to its higher overdrive which allows for a lower geared rearend. All 81-83 manual n/a cars had the 3.9:1 rearend (as far as I know). All turbo cars, manual and auto had a 3.54:1 rearend. I decided to stick with my n/a tranny and rearend setup out of simplicity and as that is what I already had. My donor car was an automatic. There is some dispute as to which rearend/tranny combo is the best. I cannot comment on which is better, but will say that I am satisfied with my setup.
Oil Cooler
From what I have read, only the automatic zx turbos had an oil cooler. The oil cooler on my donor car was slightly damaged, so I did not install it on my car. I plan on installing it in the future, if I can get some hoses made. Since my engine came with the oil cooler bracket bolted on to where the oil filter was (similar to after market setups), I did not have a nipple in my block to attach a regular oil filter to. There is also no safety pressure bypass in the block as there is on a regular L-series engine. This is of little concern, as long as you change your oil on schedule. I removed the nipple from my other engine and installed it on my block. You need a nipple from a nissan engine as it has special threads into the block.
Turbo Swap Links
Please email me your
links!
Page Created 3/17/2004
Last Updated 11/3/2020