Can a series 1 RB25 be turned into a series 2?

[Mute]

Ok, there's the whole "whats the difference between a s1 and s2 Rb25?"...I got that. Currently in my car I have a S2 and I am building an S1.

My question is this, since the difference between the two is the ignitor, the cams (I believe), CAS, and as a result the whole harness...Can those elements be swapped over to make the S1 work as the S2?

Trying not to make this complicated, hopefully those of you well versed in the ins and outs of the RB25 understand what I'm getting at.

Thanks for any help.

[Coolwhip]

the cams are the same. The motor it self is the same. Electronics devices are what seperate the motors. IF your using the same harness and coils when your swapping motors then your set.

[Coolwhip]

sorry, in other words...The harness and coils are engine specific, everything else can be interchanged over.

[eh?]

minor difference but the s1 oil pickup has an o ring groove on the flange. The S2 uses a metal gasket with no groove on the pickup.Also the S1 and S2 TB's and TPS are different along with the TPS connectors.

Also I think late late S2 had a different cas/cas drive.It's not a big deal to do the swap over.

[Coolwhip]

ah yea, good call, I forgot about the CAS drive on the two motors. I believe another member ran into that when trying to install his HKS cams on his motor.

[Mute]

Thanks for the information guys, it'll make for a better video in the end when I'm not putting everything on hold to source little parts for the swap. Really appreciate it.

[KlanjacOFF]

gonna bump this up

so the ecu does not matter with this? I can use my series 1 Ecu with the Series 2 harness and coils? And all the connectors match up besides the coils? I might be doing this because my S1 harness is ****ed up and I can get a S2 locally.

[KlanjacOFF]

come on guys, anyone know? I'm supposed to get up with him today so I need to know if I'll need the ecu or not. I guess I'm gonna go ahead and buy it all

[Carl H]

for some reason i remeber some one trying an s1 ecu on an s2 harness and it not working...which doesnt make sense as the pfc for the r33 is the same for both engines.in theroy it should work fine.

[matafied]

This was brought up before, and with MY experiance i have never got a s1 ecu to work on my S2 Ever!! plan and simple i wasted money buying 2 ecus for my s2 and they wouldent start my car because they were s1 ecus, however the s2 ecus will work on a s1 motor, like the power fc. heck i could post a vid of the ecu running my s1 and it not starting my s2

[matafied]

This is what happens when you try to run s1 coils without a igniter on a s2 ecu



notice the dark burt spots



This was before i fried it

[d356bud]

I'm currently running a s2 ecu on s1 ignition system

[matafied]

yea s2 ecu will work fine on a s1 motor

[Bluefire]

You can run s2 coilpacks on an s1 harness. You just eliminate the igniter and connect the wires direct. Also s2 and s1 coilpacks have opposite mounting points, so if you swap them make sure you get the aluminum brackets as well. Otherwise you have to tap the brackets for the new coilpacks.

Also about the cas being different, this is a very, very rare case for R33 RB25det's. Only a very few came with the black covered cas. When buying cams, early model relates to motors with aluminum cas, and late model relates to motors with the black plastic cas.

As posted above tps' are different between s1 and s2. If you swap the throttle body also, you just need to wire in new plugs and your good to go.

As for ecu's, I can only verify that S2 ecus and power fc work on both series harnesses. I have yet to try and S1 ecu on a S2 harness.

-Bluefire

[l0nestar]

I believe another member ran into that when trying to install his HKS cams on his motor.

That member would be Shocker.

[mattleegee]

So someone said above late s2 CAS wont work but early s2 CAS will work for a s1 motor?

Anyone give me the heads up on s2 CAS working on s1?