I realized something today...I’ve been a moderator here for some time now and I’ve been telling people to search for answers to this question and never realized how scattered and sparse the information in. So in an effort to un-ufck that situation I figured it is time for a real thread
Please add information or correct me if I make a mistake! This will be a sticky and possibly an article if it pans out well!!
First things first: any supplemental questions related to the swap (i.e. wiring) can be found here zerothread/110509
What should I replace before the swap?This is a very hard question because everyone’s budget is different. Not everyone can afford to spend an extra $2000+ worth of parts before the engine is even in. What I recommend to replace is: 1) Water pump 2) Timing Belt AND tensioner/idler pullies 3) Oil Pump 4) Clutch (possibly flywheel if you have the cash flow) 5) All accessory belts ( zerothread?id=119087
) 6) Fuel Filter 7) Fuel Pump (replace with higher flow unit) 8) Spark Plugs (more info comming soon)Those items will ensure you have a strong running engine for a long time. They are basic maintenance items that are overlooked by a lot of people who subsequently have engine failures.
RB20Will bolt in using stock mounts and R32 crossmember. you can also use aftermarket ones from companies such as McKinney and TopHat Will use stock 5 speed driveshaftCustom downpipe may be needed for both S13 and S14Electric fans are requiredCustom throttle cable bracket may be requiredTach adapter or gauge cluster swap required for accurate tach signal
RB25Requires electric fansCustom throttle cable bracket may be requiredTach adapter or gauge cluster swap required for accurate tach signal. Then this one gets a little more complicated. MountsR33 crossmember and mounts can be used, BUT you must cut the hood skeleton or replace the factory 25 manifold with something like a Greddy unit or similar. Mckinney and TopHat make mounts if you only have a motorset and no crossmember.
DriveshaftThe cheapest route for this is to open the phone book and start calling offroad shops and driveshaft shops. You will generally spend $225-$275 for a custom shaft if you bring them the parts. They will tell you where to measure and then make the shaft.
Shops like Mckinney do make a bolt in 1 piece shaft provided you are using their mounts but they are rather expensive.
DownpipeIn a s13 the stock downpipe clears if you have mounted via the crossmember swap or aftermarket mounts.
In a S14, it’s a bit different. Using the R33 crossmember you will probably need a custom downpipe. If you use aftermarket mounts the stock R33 downpipe will work (may vary by mounts, generally it will work no problem).
RB26First, if you are considering going with a RB26, I hope you have large sums of money at your disposal. This is a very very expensive swap. Expect to spend in the 8,000-$10,000 neighborhood to do it right. This guide is going off the assumption you will be using the stock twin turbos. Things change if you convert to single. First things first, you cant use the RB26 AWD transmission without some modification to the floor of the 240sx. There are RUMORS of it fitting without modification and AWD components working but we do not have verification yet. So ffor this guide I assume you are using a RB25 transmission.
Electric fans are requiredTach adapter or gauge cluster swap required for accurate tach signalCustom throttle cable bracket may be required
MountsNo option here, you need to go aftermarket. Mckinney.
Driveshaft Same as the RB25’s requirements.
Downpipes Again, no option here. Need McKinney downpipes.
If I have missed anything or you guys want me to add something, just post it up! Thanks NICO!