Esser's LS3 FD RX-7 R1 **Warning V8 content**
 

I figured I would post up what I have been working on over the past year. I have owned several import cars in the past including a couple 350Z's and a few 240sx's and recently started diving into the LS world with a C5 corvette. The vette is a fantastic driving car and makes great power very little money, and unmatched reliability. However, there was always a lack of interest for me in the body and interior side of things, as well as the community in general. The 90's era imports have a special place in my heart, and the ability to create a car with the monster V8 power and reliability in a lightweight chassis peaked my interest. Enter the FD RX-7.

For the longest time I have wanted to pursue a project with an FD and it wasn't until recently that i was able to jump on a deal for a roller chassis from Texas that I found on this forum. I had my mind made up before I even bought the car, that an LS would find it's home in the chassis. It was a perfect candidate: R1 model with low miles, fresh paint, and all the rotary shenanigans had already been pulled out. I do love a nice rotary, but for me this project is about making my dream car, which is an LS FD. All the benefits of the reliable torque from a V8 and the elegant, agile chassis of the rx-7 combined into one. After a trip down to Texas (a 12 hr drive) I had the project strapped on a trailer and on its way home. :2f2f:

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The R1 model was a must for me, at 6'1" I was unable to fit a helmet on in a sunroof FD. Not to mention the roof line without the sunroof has a slight dip that adds to the unique curvy look of the FD. The roller I found was extremely complete, with all interior items included as well. I am thankful I was able to find such a clean slate to start with.
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Here is my Tacoma making the long haul from Texas back up to Indiana with my precious cargo. It was a great feeling looking back into the rear view mirror to see that FD back there!
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Fresh off the trailer after a second 12 hour trip and resting in front of my house:
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I was able to start looking through the engine bay and seeing what all else had to be done, and the hours of research had begun to prepare myself to install an LS3 into the chassis. My overall plans for the build are to do it once and do it right, my OCD will help keep my cleanliness of the build in line. Ideal setup will be for a road course, but would like to keep it as streetable as possible.

Here is a good size comparison next to a C5 corvette, for those curious. It is indeed much smaller in length and width!
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My first plan of attack was to strip out the chassis and remove everything in the bay to prepare for paint. This involved pulling that horse show front harness out (huge pain) and taking out all the factory brake lines. this engine bay has been painted previously, but it was done when the engine was in the car so it is somewhat of a patchy mess ha.

Rolled it out and removed the dash to get to some of the wire harnesses a little easier. The dash removal alone took a couple hours

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HVAC system removed:
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Got the front down to bare chassis, in an attempt to start to fill in some holes and do a slight shave of the bay. I don't plan to completely smooth everything out, just a slight clean up.

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With everything removed from the engine bay, I was able to give it a good cleaning and started removing some of the unnecessary brackets and holes.

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I also siphoned out all of the old gas that was sitting in the tank for who knows how long.
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With some help from a buddy, we welded up a lot of the future un-used holes for a bit of a shaved look:
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Again, not going for the completely shaved look, just removed the un-used holes so the engine bay is simplified. I grinded everything down and hit it with a coat of rust reformer to keep everything minty until the painter can get ahold of it.

I removed the pedal assemblies and tore them down to rebuild them. It's obvious they used mild steel on these, and a light coat of rust had formed on the surfaces. I ended up soaking everything in apple cider vinegar to remove the rust, which worked amazingly well. I let them soak overnight in about a gallon of it, and they came out looking super fresh! I dried them off and before it could start rusting again I hit them with a coat of rust reformer.

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All the parts going into the apple cider vinegar:

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Comes out looking like new:

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Gave the steering column and the dash bar the same treatment:

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I figured I would go ahead and freshen up the suspension components in front and undercoat the wheel well areas before the car goes off for bay paint. I removed the front a-arm/brake assemblies and gave them a good cleaning. Everything up front is super pro bushings, and Tein flex coilovers. Debating on if I should do a brake upgrade now or down the road.

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Had to pressure wash and scrub the crap out of these wheel wells to get all the crap out:
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I used 3M professional rubberized undercoating and layed down a few coats. Love that stuff.
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Re-assembled everything and the tow truck came to take her away to the paint shop:

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At this point it had been about 4 months since the car had seen daylight, it was nice seeing it out in the open air again!

Body shop planned to knock it out in a week

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Oh yeah the day before the car left for paint, a big ass box showed up. 8) 8)

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Awesome build so far.

So unboxing the crate LS3, such a nice looking motor! I thought about buying a used for the longest time, and some deals fell through on some engine/trans combos. I eventually settled about ordered a brand new crate engine, it was not much more money than what used LS3's go for, and of course still has the GM warranty on it.

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Got it up on the stand and started taking about the brand new engine to do the oil pan swap

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I will need to be using an f-body oil pan for the steering rack clearance. I went ahead and also bought the Improved Racing oil pan baffle for the added insurance during some hot laps.

New stuff goin on:
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It's on!
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Going T56 or TR6060 behind your new LS3

Something that I put on my last LS engine was an ATI dampener, it saves some weight and has a 10% under-drive on it. Will be a great piece to obtain that "quick rev" action i'm going for.

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Pulling the stock on off with a puller:

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New one is on! The new balancer weighs about 4 lbs where the stock one was about 10lbs. I went ahead and removed the stock manifolds as well since I wont be using them. I decided to go with the Samberg/Ronin subframe assembly, so I installed their fabricated engine mounts. They look really well constructed!

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It will be a T56 Magnum (essentially a TR6060 in a T56 case)

While waiting for the engine bay to be completed from painter, I sprayed some satin black on my brake booster to freshen it up:

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Looks great so far.

Car came back from the painter looking amazing, the pictures don't do it justice. I started installing all of the brake components when I got it back.

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I went ahead and deleted the ABS system, for weight savings and the appearance factor. Not to mention I didn't have any of the sensors and I didn't want to put money into getting the system working. I chose to do the Rotary Shack's hard line abs delete kit, it took some manipulating but ended up fitting great. Installed a new gasket on the Booster and got it fitted up.

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Found some nice sized rubber grommets to fit into the holes for the passenger line.
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The kit included a Wilwood proportioning valve to control fron to rear bias:
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Wow, my dream build, FD Body and LS3 Engine :drool:

I went with the Toyota Landcruiser master clutch cylinder. It took minor modification to fit, and I did not end up doing any welding. I used the male to male thread pitch adapter and everything looks like it's going to work. The master cylinder itself is cast iron, should be pretty stout if the seals hold up over time.

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I installed the lines, and started working on the subframe. I went with a setup from Ronin, and had the subframe powdercoated from them. Install went okay, I did end up having to grind down some welds on the top of the subframe so that it would sit flush to the chassis rails. I used my grinder and took off the bumps of the welds and all is good!

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Raised welds here:
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Old subframe out and some heat shield installed:

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Used some metallic tape to clean up the edges:
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I had seen some reported failures of the samberg subframe camber rings breaking off. This was mainly due to other root causes such as the front camber bolts loosening up and allowing movement. I requested that Ronin beef up mine with some extra welds (Thanks Ronin!) and they provided. They put some extra beads around the perimeter of the ring.

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In addition, I etched in some lines on the back faces of the bolt face to help "grab" the metal on the subframe. When this gets tightened down it should help hold the alignment during hard driving/bumps.

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Steering rack freshened up and installed:

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I started working on the fuel system. I had previously emptied the tank, and had no clue of the condition inside. Being a metal tank, the possibility of rust was there, but once I pulled the stock pump I saw that everything was minty fresh! :)

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I installed my new fuel pump: a Walbro 400 lph. Should provide plenty for the LS3 even when I do some bolt-ons and cam and such.

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I did decide to go ahead and use all new fuel line instead of re-using the factory mazda hard lines. I got a big box of all my aeromotive items:
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I went 6an for everything and put the fpr up front return style. Mounted it right by the master cylinder.

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Removed the tiny fuel outlet/inlets on the factory tank cover and replaced with 6an bulkheads:

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Wrapped most my fuel lines near the bay in some adhesive backed heat sheild:

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Evap canister vented:

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It was difficult to find a place to mount the huge aeromotive fuel filter, this thing is like the size of a soda can. Should flow excellent. Only spot that would really fit it was the factory filter location above the diff:

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Looks great!

Trans has arrived! I went with a Stage 4 T56 Magnum. It is a new unit that has been torn down down and had carbon blocker rings installed and bronze fork pads installed. It's rated for 900rwtq! This one also has a Fbody tailhousing installed for ease of install into the FD chassis.

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It fit in the trunk of my civic just fine ha!
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Clutch also arrived, so I installed it onto the engine. I went with a Mcleod RXT twin disk clutch. It's supposed to hold 1000rwhp and drive like stock. It sure does look pretty tho.

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I went with a Fidanza lightweight flywheel. I am eager to see how fast I can get this engine to rev!

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Mounted the lifting bracket to the valley, and started mating the engine to the trans. This took a little bit longer than anticipated, but after some will force I made the two go together.

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Had some buddies come over to assist

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Big grin on my face! this was a happy moment!
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It's in!!!
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Badass pic I took:
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intake installed:

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Large amount of heat wrap on the fuel lines and clutch lines:

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Trans mount fitted up:
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Motor mount look really nice, tightened down the biscuits to get the engine height correct.
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Shifter alignment, needed to cut the trans tunnel a bit. Went with MGW
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Also started installing some accessories, picked up an alternator bracket and a nice power steering mount. I will be running Fbody accessories on the LS3. My improved racing strut bar fits with the LS3 in there, a couple mm's to spare ha.

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Starting fitting up the power steering pump. Since the Fbody power steering pump will over power the factory Mazda steering rack, I bought a Turnone pump reducer to try to get the flow to a more "light" feeling level.

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Installed and lines ran:
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I also mounted the extended clutch bleed line and mounted it to a bracket on the intake.

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Shifter hole block-off black installed and knob fitted. Went with a C6 shift knob, should look factory-like!

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Filled the power steering system with Driven oils power steering Fluid:

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Will be using an Odyssey PC925 battery, and fitting it under the bin behind the passenger seat.

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Made my own wire terminals for battery relocation.

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Started wiring in the engine. I went with the PSI conversions wire harness. Quality seems spot on and price is great compared to all other harness manufacturers. I 3D printed a hole size reducer so that the 2inch firewall grommet on the harness would mate up to the existing 3inch hole on the FD firewall.

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Heat wrap installed:
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I was also able to get the samberg radiator installed:

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I have done a full conversion to speedhut gauges, and thought I would share my process. I posted this DIY in the electronics section as well, figured I post it in my build thread. I was able to retain all the factory housings and bezels for a complete stealth look. I did all of this in about 3 hours, and no major fabrication was necessary for an OE look. First of all, you will need to order these sizes:

4.5" Tachometer
4" Speedometer
2-1/16" Oil pressure
2-1/16" Water temp
2-1/16" Fuel gauge

I have seen a lot of people order the smaller 4inch tach, or get the 3-3/8 speedo. Dont do this. I actually measured the holes, and the 4.5" tach and 4" speedo work perfect. They actually measure out almost identical to the diameter of factory gauges. Trust me.

So for those of you that dont know, the speedhut gauges include their own bezel (usually aluminum) and their own rings to mount them. They also have a button (if programmable) and their own plexi-glass window. We will be ditching the plexi-glass window and aluminum bezel in order to make the factory mazda pieces work.

So here is how the speedhut gauges look compared to the stock ones:

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I went with the Revolution style gauge with white font. I also had the custom lettering put on to say "RX-7" ($10 option)

First step is to remove the cluster obviously and unclip the clear lens cover and the black plastic backing from the cluster assembly.

You will be left with this:
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The stock gauges themselves unbolt from the back. There are about 3 bolts per each of the gauges. Go ahead and remove them so that you have an empty piece of white plastic (don't mess with the circuit board paper on back, we need to retain this for the turn signals) but you can go ahead and start removing the larger bulbs that screw in from the back.

Now looking at the black plastic gauge housing, you will notice that these holes are way to small for our large gauges. I used some side cuts and started making cuts into the edges of the housing. This effectively opens up the holes for the larger gauges. Then I literally threaded the gauge body into the housing. bottom them out until they sit flush at the front.

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Dont worry about being neat, this cant be seen. Gauge will "press/thread" in:

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Tach installed: notice the aluminum bezel is removed and the slider ring on the back is also ditched.
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Remove any interferring white plastic standoffs on the base of the cluster. These will be obvious when piecing it together.
Run the wires through the (now) un-used bulb holes:
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Once all the gauges are pressed in, I noticed that there are stubs on the edges of each gauge. I will need to drill out the clear lens to accept these protrusions. I put a bit of toothpaste on the tip of edge stub and then lined up the lens so I could see where I needed to drill:

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The "drill here" mark it made on the lense:

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At this point you can re-install the lens and see that everything fits and lines up like OE

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But then you will realize that you can't push the buttons on the programming for each gauge. I marked "eye-balled" where each of the buttons were with a sharpie, then removed the bezel and drilled it out to accept the speedhut rubber buttons and standoffs.

Drill slowwlllyyyyyy:
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Buttons installed:
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Standoffs put in place to reach the button on the gauge:
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Screw all the items back together and you now have a fancy factory looking gauge setup:

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I hit the expansion tank with a couple coats of wrinkle black, turned out pretty nice.

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I also completely took apart the HVAC and cleaned out all the debris. My roller is low mileage, but still had a bit of leaves and crap in the vents:

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I did some relocating, and I think I found a better spot for the expansion tank in the bay. It tucks into the corner by the wiper motor pretty well. I temporarily set it here to see how the hose routing will work.

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Heater hoses ran, and covered in some fiberglass heat wrap from RaceFlux.

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I also found a nice overflow tank and fabbed an aluminum bracket for it to sit back in the corner next to the expansion tank. Will have to go back through and clean up all the hoses, but I think i'll stick with this setup. It get the expansion tank in the highest place possible for coolant burpage.

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Also fabricated an aluminum bracket to mount the front fuse box to:

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Still trying to find a stock fuse box cover for this! Let me know if anyone has an extra they'd sell

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Great build all around!

I agree. All good stuff.

Finally had a warm weekend so a lot of progress was made. I had to remove the intake again in order to get the speedhut oil pressure sender and adapter installed. I also had to slightly trim the firewall lip to help clear the wire harness.

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It was surprisingly warm out today despite the 6 inches of snow on the ground!
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I bought a cheap Pioneer radio to install in the empty hole on the dash, and wired it up. To my surprise the retractable antenna works still.
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It was time to fill up the coolant system. I used a AirLift system, which vacuum fills the entire coolant system. I pulled a 30in vacuum on it and it took about 3 full gallons to fill. Zero bubbles and no need to burb the system with this method!

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It sucked up the fluid until it was full to the brim.

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I installed the plugs and wires, as well as some vibrant heat sleeves on the wires for added protection. Here are some shots of the "completed" engine bay. Just waiting on an oil catch can and it's basically how it will look:

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And I finally found a cover for my fuse box lol

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It's getting close!

I started re-installing all of the factory panels and bumper, it took some time to get the body lines correct again. I decided early on that I would delete the factory hood latch, and went with an aero catch setup. The install is a bit of a pain, but I was able to do a clean setup.

Started by drilling a 1.5 inch hole and working off of that.

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I chose the mounting location behind the headlight, it looks cleaner in this location IMO

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Finished result:

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Time to start the engine! I primed the oil system using a drill pump, and held it at 40 psi for a few minutes and made sure oil got into the valve covers.

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My little drill pump jig works will, I put a clear section in to see the oil going through to make sure you're pumping. I will have to upload a video, but the engine fired right up on the first attempt! It's almost ready for the first drive, just have to do a quick alignment in the garage.

Why delete hood latch? Just curious.

Love this build. Engine bay looks beautiful... I’m also thinking about going with an aero latch kit on mine but still looking for an aftermarket hood to clear my 102mm TB.
Glad to see you up and running. Have fun!

Clean LS build

My painter filled in the hole for the cable, and I decided to just ditch the hunk of metal up front. Glad I did, I really like being able to open and close the hood without going inside the vehicle.
I was able to wash the car for the first time in a year. It moved out under its own power, very promising. Clutch grabbed great, but I lost brake pedal pressure. I think my master cylinder is just bad, it grabbed a little then went to floor like it blew out a seal, got a new one on the way. Bunch of pics in the decent weather! The paint still has zero miles on it, shines up great.

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These wheels look damn good, but they are heavy mofo's being XXR. Looking to replace them with something lighter that still looks decent.

Very clean LS build :icon_tup:

Tackled the exhaust this week. Got it up on a buddy's lift and worked for about 20 hours to get this fabbed up, lots of work!

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The setup is as follows:

JTR 1-3/4" headers
3" Y-Pipe into a vibrant merge into 3.5"
Borla XR1 3.5"
Then at the end there will be an Apexi muffler

Here is the progress so far
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Here is Luis the welding Guru at work:
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That was about all we had time to complete. Hopefully next weekend we can knock out the muffler tail section. Goal is to make it less than 103db at 50 ft, which is what most tracks require.

Rear section of exhaust finally completed.

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Still trying to track down some small gremlins to get it driving correctly.

Had a semi nice day out and detailed the engine bay. It started raining moments after finishing, I should have some good video made once the weather gets nice out. It seems this winter has been drawn out a couple months too long!

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Engine swap done by yourself. Detail done by yourself, damn is there anything you can't do?. Clean car

Detailing an already detailed car. I think a new word might need to be created to truly expressed the details of this work. Very clean setup and very jealous. Thanks for sharing especially your work with the speedhut conversions. If you ever get an opportunity, a video of the car and exhaust would be great. Curious how that exhaust setup sounds.

-groovin

Really quality work! Impressive! Should be a great car.

I finally got into my appointment at the tuner. I drove the car around for about 100 miles to get things broke in, changed oil, then headed to the dyno tune!

It put down 382hp, which is right in line with what most stock LS3's do on the dyno. More importantly it drives perfect, even with the aggressive RXT clutch. Torque is everywhere!

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working on uploading the dyno vid

Really nice work. Looks stock. Congrats.

I bet she moves. Still on the 4.11 rear?

Yes still the stock rear for now, I have a hybrid TII s4 diff with 3.90's waiting to go in. Should help a bit

Finally got the vids uploaded! Dyno vid and some exhaust noises.

Loving it!

Are you running EFI live? Was it just a dyno or did they actually tune? What was target afr?

-groovin