SR20 swap guide

07-10-2004, 08:56 AM (http://)

For some reason I can't get this link to work, but the web add is there, scroll to mini projects and go to "240SR", this website provides a complete guide on hwo to install an SR20, and has part #s' and other things you need to do, precautions and measures, and so much more info, I go to get some of my info from here, I know there is info on this in the FAQ and most of you are familiar with this site, but I thought it might help the newbies and anyone who wants a step by step guide. Has little shortcuts to do this too.
Hope it is of use to anyone.................................

07-10-2004, 08:57 AM
Here is the first column. Sorry but the pictures don't transfer, so if you want pics, go to the site.

Project 240SR
Part 1: Engine Swap Preparation

By: Joe Lu and Charles Johnson

With Project 240SR, we will be transforming a bone stock 240SX hatchback into a potent street weapon with a robust SR20DET transplant. We took a top-down approach towards this new project, first attacking the biggest and most costly modifications under the hood, and leaving all other areas completely neglected for the time being. In this installment, we will discuss several areas of engine preparation, which will make the SR20DET transplant both easier and more successful at the same time.

Having clocked mileage far beyond the century mark on the odometer, the tired KA24DE that took residence in our engine compartment was nearing the end of its useful life. Our first test drive in the KA24DE-powered rattletrap confirmed our suspicions and was enough for us to begin making phone calls almost immediately after receiving the title. After several phone calls and a week of research, we turned to Marco Vargas at, who carries the cleanest inventory of SR motors we have seen yet.

Marco provided us with a very clean S13 blacktop engine along with all the parts necessary to complete the swap. We recommend buying a complete engine swap, which includes the transmission, igniter chip, ECU, MAF sensor, intake elbow, and wire harness. Unless you suffer from some kind of migraine fetish, do not buy just the engine and transmission from some scam artist on E-bay.

Before purchasing any SR engine, there are a few key areas that should always be inspected. First, remove the oil cap and inspect the #1 cam lobe with a flashlight for any scoring (Remove the entire valve cover if you can). The needle-sized ports on the SR’s oil delivery tube are prone to clogging over the number one cam lobes and can quickly cause engine failure.

Secondly, a common problem with an engine that has traveled halfway around the world sitting on its oil pan is exactly that, the oil pan. The SR20DET is particularly picky about having a dent free oil pan, as a few dents in the right places will block the oil pick up tube and starve the engine of oil. This of course, will lead to premature, if not immediate, engine failure upon start up. We were fortunate in that our oil pan had no serious dents, but decided to be safe and bang out the small dents that were there. Once the oil pan’s bolts are removed, we used a thin piece of sheet metal to slice through the RTV and remove the oil pan. Do not use a screwdriver to pry off the oil pan, as it will mangle its flange. With the pan removed unscathed, we banged out the small dents with a hammer. Before installing the oil pan, make sure to scrape off all the old RTV before applying more and putting the pan back in place.

Lastly, remove the spark plugs and inspect them thoroughly for signs of foul play. A normal plug will be a tan color with white speckles. Spark plugs are often considered an “eye” into the engine and can provide valuable insight into an engine’s past life. For example, an oily spark plug can be evidence of failed piston ring.

Along with our engine, we also picked up a Silvia radiator, fans, and shroud. Although these are not necessary and the USDM radiator can be used, we opted for the JDM unit since it would produce a cleaner appearance in the engine bay. The top radiator hose on the USDM unit is located opposite of its JDM counterpart and requires some rerouting of the hoses from one side of the engine compartment to the other.

While the engine had been cleaned very thoroughly and looked new on the outside, its past life in Japan will forever remain a mystery. Due to this fact being true on most imported engines, it is always a good idea to change the clutch while the motor is out of the car and the transmission is easily accessible.

For our clutch, we contacted Jason Garrett Young, owner of JGY Customs. JGY Customs is one of the few shops in the U.S. that specializes strictly in Nissan performance, stocking a full array of OEM and aftermarket components, and also having completed numerous SR20DET swaps. Jason recommended an ACT clutch kit (#NM1-HDSS) for our application. The ACT clutch consists of a Heavy Duty Pressure Plate with a modified street disc. This kit is meant for a 1984-2001 Nissan Maxima, but is also applicable for use in the RWD SR20DET. Its torque capacity of 362 ft-lbs should be more than enough to handle our SR20DET on stock boost and any future upgrades.

Before installing the clutch, the flywheel was taken to a local shop to get resurfaced. When installing the clutch, make sure the flywheel is free of dirt or oily finger prints. We used Simple Green to degrease the surface of the flywheel. After everything was nice and clean, the flywheel, clutch disc and pressure plate were assembled. Be sure to use the alignment tool to center the clutch on the flywheel so the bellhousing can be reattached to the engine. After a few minutes of frustration and wrestling, the transmission reunited with the engine encasing a tougher clutch with a bit more holding capacity.

Heater Hoses

Before installing the motor into the car, it is important to re-orient the hoses on the rear of the engine since they will be impossible to reach once the motor is installed.

The first hose that needs to be altered is a metal line, which is bolted directly to the motor. This line can be removed since the hose connected to it will no longer point in the same direction.

After removing the hard section of line, bolt the turbo coolant line bracket back into the block (you may need to gently bend this line slightly).

Find a suitable piece of hose, trim to fit and reconnect the line.

Take the two heater lines and turn them so they face towards the passenger side of the car.

In order to extend these hoses, we purchased two brass ¾” - 3/8” brass reducer couplings and a heater hose with a 90 degree bend. You will need connectors as the Japanese hoses and American heater core nipples are different diameters.

After re-routing the appropriate hoses, the heat shield from the turbine housing will need to be removed in order to clear the steering column. Also for our swap, we decided to remove the AIV pipe and plugged the opening in the down pipe using Nissan part number 14052-21R00.

Lastly, before installing the engine, we decided to perform a mock fitting of the wiring harness, matching each plug with its respective sensor on the engine. Once we located each sensor, we labeled the plugs with numbers for easy identification later. This step will prevent you from having to hunt for missing connections after the engine is in the car. If this is your first time performing an SR swap, this step will help familiarize you with a seemingly rat nest-like mess of wires.

With the preparation complete, the fierce turbocharged SR20DET is now prepped to free our Project 240SR from the miserable performance of the old motor. In our next update we will cover the installation of the new powerhouse into Project 240SR. Stay tuned.

07-10-2004, 08:59 AM
Here is Column II, there are more, you can go there for the remaining articles.

Project 240SR
Part 2: Installing the Engine

By: Joe Lu and Charles Johnson

For this segment of Project 240SR, we will turn our attention to the installation of our prepped SR20DET. For this undertaking, an engine hoist with a load leveler will make engine removal and installation a lot easier. Also, place a towel over the valve cover to protect it during the swap. Our SR20DET came with an unblemished black top and we preferred to keep it that way.

Now, for the real work... Start by draining all of the fluids from the KA. Drain the coolant and remove the stock radiator if you are using the JDM unit. If not, remove the radiator anyway so you have more room to work. Next, drain the transmission and remove the shifter for clearance. If the transmission is not drained, it will its guts all over the garage floor (yes, it happened to us) and there are few things that smell worse than old transmission fluid. Don't forget to also drain the power steering and clutch lines as well. Make sure all hoses and lines are disconnected. This includes air conditioning, power steering, fuel, clutch and the heater hoses.

While the fluids are draining, disconnect the KA wiring harness from the engine and remove it from the vehicle. Save it, so you can use factory wire to extend the plugs of the SR harness. Next, unbolt the down pipe portion of the exhaust manifold from the catalytic converter. Make sure you have purchased a 3 inch down pipe to use with the new SR exhaust manifold as this part is not included with most motors. For our down pipe, we again turned to JGY Customs for their Topspeed 3" stainless down pipe. This piece performs just like its Greddy and HKS equivalents, but costs less and looks great with a polished finish.

Also unbolt the driveshaft from the transmission.

The crossmember which bolts to the transmission's bell housing should also be removed at this time.

With the engine supported by the lift, unbolt the right and left engine mounts and begin to hoist the engine up. Tilt the front of the engine upwards so that the transmission can clear. It will be a tight squeeze, but you can remove the engine and transmission together. Make sure the KA engine does not hit the power steering lines, the steering columns, or anything else. Also watch out for overlooked wiring that is still connected. If thoroughly prepared, the engine should come out with relative ease.

While you have both engines on the garage floor, remove the KA air conditioning compressor and see if any of the bolt holes match up on the SR20 block. Some KA compressors will bolt through three holes, others simply wont line up at all. Ours didn't, so we just kept the SR20 compressor in place and left the hoses disconnected for the time being. We will have new AC lines welded together in the future.

Once the KA is removed, its time for the most important step in any engine swap. Jump inside the empty engine bay and strike a retarded pose. Now is also the time to spray simple green everywhere and clean up a bit.

To make the install go easier, you could remove the engine mounts from the car and bolt them to the engine. We regretted not doing this, as lining up the studs with the hole in the engine mount is a rather inconvenient pain in the rear.

Before dropping your new SR20 in place, don't forget to remove the dust boot from the KA transmission to use on the SR20's. The KA dust boot is a thin metal ring, carefully pry this out. The SR dust boot is a thicker rubber ring but will not clear the KA driveshaft. To install the KA dust boot on the SR transmission, lay a piece of wood across the boot and work it in evenly with a hammer. It may take a bit of encouragement, but it will fit.

Next, drain the oil and change the oil filter since filters often seize on imported JDM engines and everything is still easily accessible. Put in three and a half quarts, saving a half quart to prime the oil pump later. Then remove the shifter assembly off of the SR20 transmission.

Attach the SR20 to the engine hoist and position it for entry.

Be careful when putting the engine in, you can't just drop it in there, you have to ease it in. It will take a lot of adjustment with the load leveler to get the steep angle which will allow the transmission to clear the front of the car. Once the engine is in position, bolt in the left and right mounts and reconnect the crossmember, then the driveshaft. Leave the engine supported while working under the car. Now, install your down pipe and connect the exhaust. Don't forget to transfer the rubber mount from the stock downpipe to the new one. You will also need a gasket to go between the downpipe and the exhaust manifold. We found Victor Reinz p/n F10110 to be a perfect fit.

Also install the JDM radiator and shroud.

The passenger side of the shroud will need trimming to clear an A/C component. We needed to trim the bottom rubber mounts on the radiator as it seemed to sit a bit higher than the original KA radiator. It is an easy task, just cut off the excess rubber with an Xacto knife.

Next, bleed the hydraulic clutch. This is a pretty big pain in the ass with the clutch dampening box in place. We discovered this after trying to bleed the clutch several times unsuccessfully. The clutch damper box is bolted to the underbody of the car and runs from the clutch master cylinder hard line into the clutch slave cylinder. The box is there to eliminate clutch pedal vibration and pulsation; but makes bleeding the clutch damn near impossible since it is very prone to trapping air.

To remove the box, disconnect the lines running into and then unbolt it from the chassis. Then connect the clutch hard line straight into the rubber flex line that runs into the clutch slave cylinder. Now is the time to replace the flexible rubber line with a steel braided line. We were pressed for time, so we just connected the stock rubber hose to the hard line. Remember to use a flare nut wrench on all of the hydraulic fittings. Stripping these fittings will lead to hours of additional repair. Now bleed the clutch with fresh brake fluid.

With our new SR20DET securely taking up residence in our project 240SR, we will turn our attention to completing the swap. Stay tuned, as next month we cover the electrical work necessary to bring the SR20DET to life.

wiring specialties
09-02-2011, 07:00 PM
Just to add to this thread with a friendly reminder.
If you need brand new, turn key wiring harness for you swap, check out our site. (

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