About to start an RB swap, but I have a couple n00bish questions...

[masticatingcow]

Uh, I guess I'll cut to the chase:

1. Does the RB20DET need a custom driveshaft to work with the S13 rear end? I searched and searched and I couldn't find any threads here or anywhere in which that was brought up. I assume the answer is NO, but I wanted to double check.

2. I've noticed a lot of you guys running RBs without fans. Am I blind or are they unnecessary or what? I was planning on installing a Flex-A-Lite when I do the swap, but is a Koyo enough? Also, I read somewhere in the 240sx General threads that the KA and RB radiators are the same... can anyone verify? If that's the case, of how much use is the stock KA radiator?

Anyway, I'm getting a clip from Venus (I'm going to go and get it... shipping's a bish) and I'm not afraid of extended downtime or custom work. I'm doing this swap with the intentions of getting my hands dirty and learning a LOT. For better or worse, the RB stole my heart and now you'll see me on these threads more often, asking deceptively n00besque questions.

So I appreciate any help anyone can give me. Thanks in advance!

[Andrew85cm]

Wow those are noobish questions but I was once there and still have the occasional duuhhh... moments so I will help ya out. As far as driveshaft. No the length of the driveshaft is the same when swapping a rb20det into a s13 as long as it is a manual driveshaft. If you have auto you can't use it. The main issue I see is the fact that your engine and transmission will sit differently than the engineers at nissan intended with the KA24. These differences are generally small depending on mounting choice. I was considering a driveshaft because I was having many problems with mine but I figured out the issue and it was something else. Most people I know run the stock driveshaft so you should be fine but a one piece is lighter and will deal with any angle created with the rb20 sitting in the 240 chassie. In short the stock driveshaft is fine to use.

For the radiator most people actually run the stock SOHC and DOHC radiators from the 240. I am running a RB20 radiator which works well and actually pretty much the same as the SOHC radiator I had in there previously. All will cool it enough but if you have the money a Koyo will cool better and has a bigger capacity. So it would be beneficial. All of us run electric fans as pushers maybe thats why you dont see them in the bay. We all run fans it would be dumb as **** to not. Your car will overheat in a second at a redlight with out them. Flex-a-lite is good but there are cheaper options that flow just as well. I used to run dual 10" fans. Now I am running a 14" and a 12". The tens worked fine but I cooked them while doing some wiring. I would get 2 10" or 2 12" and they should do you just fine. Set them up as pushers as in not inside the bay and you will be fine. There is not much room between the radiator and motor so fans on that side is almost impossible with the belts, especially with a koyo which is thicker. Hope that helps.~ANDREW~

EDIT: One more thing these topics have been covered a dozen times at least on this forum and 240sxforums.com so you must not have searched too hard. I myself have replied to many threads about these same issues. Keywords= fan/s, radiator, driveshaft.

[masticatingcow]

Thanks for the help.

[sean8564]

Answers #1 No you can use the same driveshaft if you have a manual There are many compaies thamake mounts http://www.mckinneymotorsports.com most expensive http://www.e-emotorsports.com Sit lower in the car make it look like from factory and you can use strut tower bar http://www.tophatperformance.com good mount as well holds up to a lot of abuse. #2 Yes we use electrical fans and the Rb is the same as the KA and CA.#3 venuse has a good customer service rep but they send out a lot of dirty motors so have them leak and compression test before you buy it and if you are getting a clip i have seen companys do a start up test. MAKE SURE you GET a Warrenty with that motor.

[Wulfgang]

Just for clarification, the KA and RB radiators are NOT the same. But you can use either one. The RB radiator is slightly taller and slightly thicker than the KA radiator, but the useable area is the same once you install it in a 240SX because the airflow does not change.

[Eikon]

http://www.e-emotorsports.com Sit lower in the car make it look like from factory and you can use strut tower bar.

Not that it's a big deal... but just to be clear on something.

We decided in a previous thread that while the E-E do lower the engine and work very well, they still do not allow you to use the a strut tower bar. The RB20det from a skyline gts-t has a blow-off/recirc valve attached to the crossover pipe. That valve sits right in the middle of where you need to put the strut tower bar even with E-E's mounts.

You can get around it one of two ways.. A.) Get a cefiro crossover pipe and an aftermarket blow-off valve. The cefiro didn't come with the blow-off/recirc valve stock, so it has a clean pipe that leaves room for the strut tower bar. You can use the R32xmember with stock mounts to make this work B.) Get a triangulated strut tower bar that attached to the firewall. They are much more expensive, but are better than the normal straight bar because they give another point of connection and really stiffen the chassis.

[OKRB20DET]

i cant seem to find any info on the E-E web page about their rb20 mount kit

[Eikon]

Here is the thread about E-E's Rb20 mounts with all the info you need. Call Eric to find out more.

zerothread?id=114368

[masticatingcow]

venuse has a good customer service rep but they send out a lot of dirty motors so have them leak and compression test before you buy it and if you are getting a clip i have seen companys do a start up test. MAKE SURE you GET a Warrenty with that motor.

Thanks for the heads up.

[DriftFactory]

Damn Man, why didn't you call me and let me know you're getting into this mess. lol. CALL!!!