RB25/FD Build
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Joined: May 2010
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From: Clearwater, FL
RB25/FD Build
I’ve always loved the body style of the FD ever since I first saw it. I finally bought one back in February of 2005 and I’ve been working on it ever since. I'm starting this thread so that I can share some of the things I have already completed on this build. I understand that some of you may not like my choices but I'm not doing this for anyone else. With that being said, if you have any insults about my choice of swap, keep it to yourself. I will however listen to and consider any productive advise on my process so check it out and enjoy my build.
Thread Starter
Joined: May 2010
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From: Clearwater, FL
After two blown rotary motor, I took a break from working on the car to rethink of my approach on my project. My brother showed me a picture of an RB26DETT in an FD and I told myself I was going to do it. These are a few pictures of the car summer of 2007 when I began the swap.














Thread Starter
Joined: May 2010
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From: Clearwater, FL
I decided on the RB25 because it came with a RWD manual transmission for $2500 shipped. I know some will say that the RB26 is stronger than the RB25 and I would agree with you because it is but I already knew that I was going to do a complete build which means completely tearing down the motor and building from the ground up making the 25 stronger than the 26 so the 25 was the cheaper option since I only needed the block and head 







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From: Clearwater, FL
I'm not sure where I'll stop as far as the mods. I can say that I plan on upgrading every part that deals with performance. I'm building a street/road course so my next big challenge after the car is running is suspension and brakes.
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Joined: May 2010
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From: Clearwater, FL
Once I knew how the motor sat under the hood, I was ready to start cutting the firewall so the motor and transmission lined up perfectly. Pics of the firewall, motor, and trans lined up.



I have a temporary trans brace right now but I will be getting one made soon. Pics will be posted after brace is made.


The reason for cutting the firewall was to move the motor and trans back so that my shifter would be centered.



I have a temporary trans brace right now but I will be getting one made soon. Pics will be posted after brace is made.


The reason for cutting the firewall was to move the motor and trans back so that my shifter would be centered.
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Joined: May 2010
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From: Clearwater, FL
Once the motor and trans were lined up, I took the car to my friends shop and had him weld the firewall. I didn't like how the firewall came out so I'm planning on getting it redone before I decide to paint.

I also took apart the entire front end and replaced the front rotors, brake lines, cleaned control arms, and powder coated the subframe.





I also took apart the entire front end and replaced the front rotors, brake lines, cleaned control arms, and powder coated the subframe.




Last edited by razsays; Jan 2, 2012 at 08:51 PM.
Thread Starter
Joined: May 2010
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From: Clearwater, FL
While everything else getting done, the block was built by my brother, greddy intake installed, and exhaust manifold with 44mm tial wastegate also installed. Spec clutch bolted to motor and ready to drop in. This is not the clutch of choice but it will work for now until I can spend more money on a better one.












Last edited by razsays; Jan 2, 2012 at 10:00 PM.
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Joined: May 2010
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From: Clearwater, FL
I had to add 1" spacers between the subframe and motor mount because the oil pan was sitting on the steering rack I still need to figure what bushings I'm going to use. The hood clears with no problems as of now 







Last edited by razsays; Jan 2, 2012 at 10:06 PM.
Thread Starter
Joined: May 2010
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From: Clearwater, FL
Cutting the firewall and moving the motor and trans back gave me space to do a v-mount setup so I ordered the core and had in welded together.
Making templates for endtanks.


Finished cooler: bell core, endtanks were made from 3/16" think aluminum plates, 3" in/out.




Making templates for endtanks.


Finished cooler: bell core, endtanks were made from 3/16" think aluminum plates, 3" in/out.




Thread Starter
Joined: May 2010
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From: Clearwater, FL
Take two steps forward only to take one step back.... I ran into a bit of a wall.... It looks like I'm going to be a little to close to my brake booster with my down-pipe so I'm going to get a new custom turbo manifold made.

I used a 3" piece of inter-cooler piping to see exactly how close my down-pipe would be to the booster. I've confirmed that I need to fix this problem. Definitely don't want my brakes failing.


I used a 3" piece of inter-cooler piping to see exactly how close my down-pipe would be to the booster. I've confirmed that I need to fix this problem. Definitely don't want my brakes failing.

Very nice. If you don't know already, depending on your year rb25 the crank snout only half engages the oil pump. At high HP (~500hp) and/or RPM (right around redline) levels you'll destroy the oil pump. There are collars for the snout to correct this.
Thread Starter
Joined: May 2010
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From: Clearwater, FL













