Published 2009
S13 SR20 Transplant in Your Datsun Roadster
First off let me thank Michael Spreadbury for sharing his expertise and experience with this swap. Michael and a group of his friends have been doing these swaps for a few years now. I would also like thank Alexi Nebbeker and Travis Rowe for leading the way and providing me with their lessons learned on the swaps they did plus some hands on help. As to the SR20 you have several choices--either the S13 or S14 SR20DE which is fuel injected and the S14 SR20DET which is the turbo fitted version. Travis Rowe fitted an SR20DET into his 66 roadster. I chose the fuel injected S13 SR20 to put into my project. Too much plumbing for the SR20DET for me. The SR20 rear wheel drive is a Japanses Market only item so parts are not plentiful stateside. Michael carrys some gaskets, oil pans, water pumps and other small parts. A few parts are interchangeable from imported models. Parts that come to mind are clutch for a '89 Maxima GLE. Many of the motor parts from a 90's NX2000 with the SR20 motor will fit.
Frame modifications are required to get the SR motors to fit in the roadster properly. Once they are mounted they look like they belong in the engine bay. Michael and crew notch the front crossmember and the x-brace so the tranny will fit. You must notch the front crossmember. I chose to cut off the front two legs of the center x-brace and weld in new pieces just as Alexi did on his. I started with a bare '69 2 liter frame I picked up from Mike Young. **Pictures go here***There are several other notches required-one for the alternator and depending on how you do it--one small one for the oil filter so you can remove it. A kit with all the mounts would be very hard to come up with as each installation has its own unique characterisitics.
Michael uses 510 motor mounts. Alexi came up with an alternative. Jeep CJ5 motor mounts Summit Racing P/N ENS-3-11086 and a Chevy tranny mount. These are made out of eurathane and should be alot more durable and last longer. When you first set the motor you will swear there is no way those mounts will work but trust me they work great.
Michael uses an internal fuel pump from an Accura Integra. Alexi chooses to use an external fuel pump from a 75-77 fuel injected 280ZX with the return run into a tee where the vent for the gas tank filler tube is located. I think I will go with the Accura internal pump on mine.
- Here is a list of some of the notes and parts required to complete this project. They include: Motor mounts from a CJ5 Jeep Summit Racing P/N ENS-3-11086(Black)(AN)
- Chevy Tranny mount Summit Racing P/N ENS-2110G (Black)(AN)
- 93-95 Subaru Justy Alternator 55 Amp--$80.00(MS)
- 87-93 V-Tec Honda Del Sol 2 row radiator--around $120.00 new(MS)
- Water pump pulley from an 80's 300ZX turbo-$8.00(Junk Yard)(MS)
- Water pump spacer(M Spreadbury--$35.00(Spriso Motorsports)(MS)
- 75-77 280ZX tandem brake master-$115.00(Kragen)(MS)
- 75-77 280ZX external electric fuel pump-$60.00(Junkyard)(AN)
- 12 circuit painless wiring kit-$215.00(Ebay)
- New 3/16" brake line stock and fittings-$30.00(Summit Racing)
- Clutch kit for an '89 Maxima GLE-$110.00(Ebay)(MS)
- Throw-out bearing and pilot bearing for an '86 200SX(KA Motor)-$18.00(Kragen)(MS)
- New oxygen sensor and nut '95 NX2000(MS)
- 1/4" plate steel motor mounts and tranny mount
- 1/8" plate steel-patches, bracing and reinforcing frame
- 4" steel square tubing for new front cross member pieces
- 1-1/2" steel square tubing for tranny mount
- The NX fuel rail should fit the spacing for the injectors, though you may need to tighten it down with the hardware after adjusting the holes to match the S13 intake plenum.(MS)
- The hole in the exhaust manifold can be welded shut, you will not use it (and yes, it was for the EGR)(MS)
- As for the water neck, what we do is rotate the housing so the water neck faces up, and then I cut off the water neck and replace the tube section with a peice of mandrel bent aluminum from a Ford Escort intake plenum.(MS)
- Use a gas pedal assembly out of a 240sx or look for a KA24 setup and use it. You can completley remove the old roadster gas pedal assembly(AN)
- External electric fuel pump out of a fuel injected 280ZX. You must run fuel injection line from the fuel pump to the fuel rail. Running the early style gas tank you must put a tee in the vent line for the fuel return(AN)
- Z31 throttle cable (84-9 300ZX), but there are lots of different versions which you can use. Just measure the length that you need and take a walk around the wrecking yard until you find something that matches(MS)
- The water pump/alternator belt which we use is a Honda Civic 1995 AC belt, I will dig around and see if I can find the part number for you. Honda belt part number 38920-P2A-003.(MS)
- Here is another part number for you: 21503-40F65 240SX lower radiator hose with fan switch. This is the factory Nissan 240SX lower radiator hose which has a built in coolant temp sensor. Get it from your local Nissan dealership. You will have to cut and modify the hose, but it will work great(MS)
- Exhaust flange from an NX200, 200SX(KA24) will bolt up to the S13 exhaust pipe. Should be widely available at the junk yard(AN)
- If you plan on using a mechanical oil pressure gauge-remove the sensor from the block and tap out for the oil pressure adapter(AN)
- Use a 240SX clutch slave cylinder(MS)
NOTE:MS is Michael Spreadbury of Spriso Motorsports and AN is Alexi Nebbeker of DATSUN Inc.
There will be other things and they will be added as they come to mind.
Some of the caveats include removing the dust shield from the front of the 1600 driveshaft. There are a couple of spot welds you need to drill out and it will pop off with a couple of whacks of a hammer. You need to have the drive shaft shortened. How much depends on where you set your motor. A front wheel drive fuel rail will clean up the installation as the input and return will be at the rear of the rail instead of in the middle.The oil pan is very small and cannot afford to have any dents in it. Replace it if it is dented at all. Michael has new ones.