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Discussion Starter #1 (Edited by Moderator)
How to Convert N/A L28 to Turbo (Please Sticky This)

This is for those of us who are intimidated by the search results, don't know what to type in, or don't want to get flamed when we ask how to turbo the N/A L28.

Why not an engine swap? Because for every 10 N/A Z's there was only 1 Turbo Z made... per one forum post. What does this mean? Lots of wrecks and blown motors and as time goes on, it's getting harder and harder to find a turbo motor. And even when you do, it could still be riddled with problems and was probably driven mighty hard in it's lifetime.

First point. IT CAN BE DONE. This is the most common question I found when searching the forums. Not HOW to do this, but IF it could be done. Yes it can.

Is Turbocharging the L28 Safe?:
Tony D said:
"It's called the L28ET.
Anybody telling you it's not safe is misinformed."

Is there any NEW information on Turbocharging a 30+ year old car?
Nothing has changed in this regard since 2002 when Megasquirt became available to solve the Programmable Fueling/Ignition quandary present when using the stock ECCS. Other than parts pricing increases, that's it, all the 'old threads' are 100% applicable.
Can I use the stock engine block?: Yes! The new engine blocks are supposed to have siamesed cylinders which supposedly helps with rigidity. Nissan later came out and stated there is no difference between siamesed blocks and non siamesed. Source: http://datsunzgarage.com/engine/

There are four points to consider on stock N/A Components:
  • The P90 & P79 Head on Late model L28's are desirable because of the shape of the exhaust ports AND larger combustion chambers. But not required!
  • N/A Blocks have a higher compression ratio which could lead to "problems" under high boost (over 11-14psi). Lower the compression ratio and upgrade the EFI to avoid these "problems". (Use a 2mm headgasket and you should be able to lower the CR to 7.8:1)
  • The N/A Intake manifold is "restrictive" according to some. If you're planning to run high boost, eventually you'll want a custom manifold or shave the existing one.
  • The stock N/A cam is "ok" to a certain degree on low boost/under 250-300hp. You'll want an aftermarket TURBO cam after that. Before purchasing an aftermarket turbo cam ensure it will work with your head! Contact the manufacturer and specifically ask if X cam will work with Y head FIRST!

This was one of the most useful parts lists I found: Click Here Because There is More Information!!

NismoPick said:
Option#1: The more expensive and thorough / reliable route:

The list is thus:

  • Turbocharger
  • Downpipe
  • Oil in & dump lines
  • Oil T from pressure sensor
  • Exhaust manifold
  • Intake J-Pipe
  • Oil pan
  • Injectors
  • Entire EFI harness (including all relays)
  • Coil ignition harness
  • ECU
  • Fuel pump module (82-83T)
  • Drop resisitor (81T)
  • AFM
  • Distributor
  • Oil pump / distributor shaft
  • Coil bracket w/ ignitor
  • Fuel pump
Optional parts that would facilitate the process:

  • Intake manifold
  • AAC / EGR actuator pump (only if you want those items to work)
  • AFM to turbocharger accordion connector boot
  • Thermostat housing w/ all sensors
  • CHTS (if current chassis doesn't have one)
  • TPS (n/a is 3 prong, turbo is 2 prong)
Option#2: The cheapskate route:

  • Exhaust manifold
  • Turbocharger
  • Downpipe
  • Oil in & dump lines
  • Oil T from pressure sensor
  • Turbo injectors
Option#2 additional requirements:
You will need to drill a hole in the left side of the oil pan and weld on a bung for the turbocharger oil dump. You will also need to fab up an exhaust coupler for the 2.5" downpipe to hook into your 2" or 2.25" stock exhaust. And you will need to fab up pipes & couplers to run the compressed air from the turbo out to throttle body. Also, depending on the year of the motor, the intake PCV valve will likely be right in the way of the turbo out. You will need to either cap it and place the PCV elsewhere, or fit a very tight 90* bend on it to get it out of the way. Lastly, if your chassis has the recirc ball steering, you will need to trim the turbocharger wastegate bracket to fit around the steering box.

You will also need to tune the AFM and timing to keep the A/F ratio within acceptable ranges.
L Series Engine Calculator if you'd like to figure out how to lower the compression ratio (Pick L28 from the Engine Dropdown and click "calculate"): http://atlanticz.ca/zclub/techtips/calcs/engine builder/index.html

Z Car Turbo Techtips: http://atlanticz.ca/zclub/techtips/turbo/

Stock EFI Problems?: http://forums.hybridz.org/topic/67673-l28-efi-problems-efi-bible-step-1-a/

Installing Megasquirt Aftermarket EFI in your 280ZX: http://www.diyautotune.com/tech_articles/how_to_megasquirt_your_280zx_turbo.htm

ZCar Megasquirt Write Up: http://www.zcar.com/forum/10-70-83-tech-discussion-forum/294570-how-install-megasquirt-spark.html

The Ultimate Turbo FAQ/Beginners Guide: http://forums.hybridz.org/topic/19918-the-ultimate-turbo-faqbeginners-guide/

Cam Swap Info: http://www.zdriver.com/forums/240z-...ket-cams-cam-removal-installation-pics-19939/

N/A to Turbo Writeup (post #3 ): http://www.zdriver.com/forums/280zx...-swap-might-well-try-organize-write-up-32792/

Aftermarket L28 Fuel Rails: http://forums.hybridz.org/topic/99098-pallnet-fuel-rails/

zcar.com said:
And Finally:

bonfire79 said:
i have had this conversion done on my 76 280z, so i will give you some info on the setup. it can be done. but, you should decide on either doing a complete turbo swap from a ZX or the conversion. either way, you will have to make changes and spend money.

i chose to to do a bolt-on turbo conversion, using original n/a components, some with changes and modifications. either way, your electronics for your fuel system need to match. here is what i have:

- original n42 head w/dished pistions and rings (stock).
- original n42 n/a block. no changes.
- late model turbo AFM with n/a internal circuit board. (swapped)
- stock n/a ECU and harness
- turbo injectors 35-45 lbs (i used ones from a BMW) or ZXT will do fine
- stock n/a oil pump
- stock cam and crank
- turbo oil line nipple welded onto the oil pan (or swap for turbo pan)
- aftermarket inline fuel pressure regulator with gauge
- German turbo fuel pump from a Volvo turbo (u can use a wahlbro also)
- 1/2" fuel line from fuel pump up to fuel filter
- aftermarket filter and larger steel braided fuel lines going to manifold
- aftermarket fuel rail
- 7th injector inplace of cold start valve
- BMW throttle body
- T3/T4 turbo (54 mm if i remember right) with 7 lbs spring for boost 7 psi
- custom exhaust manifold and exhaust system
- small intercooler
- MSD ignition box and 8mm plug wires. NGK plugs -- no exceptions!
- n42 intake, ported and shaved.

the car runs far quicker with just the stock boost, way more than it ever did without turbo. just like Tony said, even with low boost on an n/a turbo conversion, you will see a big difference.

sometimes, it may be easier to do the whole swap, still, your ECU will need to match everything else, hence full turbo swap from a 280zx. the choice is yours. i am quite happy with my setup. and i have heard that you can run more boost safely on an n/a turbo conversion, if you really wanted to.... but i wouldn't push it. you will be more than happy with stock boost, unless you have a constant need for more speed.

hope this helps.

btw, helpful info at this link. - http://www.datsunzgarage.com/
learn about the different heads, pistons, blocks, rear ends, and transmissions that came on everything from the 240z to the 1983 280zx turbo. read read read!

Was a retro (old school) kit EVER sold for the N/A or is this a recent phenomena!??! Why yes, thank you "black gold man" for Turbo Tom: http://dailydatsun.com/tag/turbo-tom/ - Turbo Tom Kits - https://www.youtube.com/watch?v=HmF1rUa8EkM

If after all this information you would still like to swap in an L28ET here is a great write up on the process: http://www.strausz.us/zcar/turboswap/

Feel free to add to or modify this thread and please make it a sticky for folks like myself just getting started on this. Thank you!

Premium Member
40,978 Posts
Please add suggestions to this link, and the OP will add them if he feels they should be part of his post.
Thanks to those of you who commented to his original posts who had their links and suggestions already incorporated. Your threads have been deleted in the hopes that one thread will be digested by the ADDHD set we have coming over the summers. It's in one place. If I see people posting "Turbo to NA" posts after this...I think summary deletion will likely be the result. It's a sticky in the page now!

56 Posts
Discussion Starter #4

all nissan z cars
1 Posts
No it's not an easy swap, it's not super hard, but not just a bolt on.:unsure::rolleyes:
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