'93-'95 3rd gen RX-7 / Chevy LS1 V-8...
...Getting Started

...Finally, The Actual Conversion...

Jacking & Supporting Your RX-7...
...Be very careful when jacking up and supporting your RX-7. The Mazda engineers went to great lengths to build these cars as lightweight as practically possible, and that meant using much thinner metals than you may be accustomed to. The sheetmetal "frame rails" under these cars are made from around 18 ga. sheetmetal, about as thick as your average oil pan. A bend or kink can significantly weaken their stiffness. As they are easily damaged and repair is difficult, it is much better to avoid damage in the first place.

Fender Covers...
...Now is a good time to get these out, before you do any damage. Thick blankets can also be used, and will prevent any paint damage should a wrench or socket be dropped on the fenders or nose area.

What To Squirt W/ Penetrating Oil...
...First thing after the car is safely in the air & properly supported, be sure to hit all the bolts/nuts in the following :
...Exhaust manifold studs/nuts
...All other exhaust bolts/nuts
...Engine subframe bolts/nuts
...Upper front strut tower bearing plate nuts
...Lower control arm inner pivot bolts/nuts
...Steering rack to subframe bolts/nuts
...Rear driveline to pinion flange bolts/nuts
...A little squirt now can save a lot of busted knuckles and cussing later.

Disconnecting The Battery...
...12mm wrench
...It's best to do this step now, before you melt any wrenches or damage any electrical components. You might as well remove it now too.

Draining Your Cooling System...
...Be sure to drain both the radiator and engine. Catch the coolant in drain pans, not only to save it or dispose of it properly, but to keep the work area neat & clean. Antifreeze does not evaporate very fast, and can hang around for several days if not cleaned up. This can expose both your and the neighborhood's kids & pets to a toxic substance.

Removing Your Hood...
...Blankets or protective pads
...12mm socket & ratchet
...Marking paint or scribe
...Place blankets or pads on the cowl area of the body and fenders. This will protect your body and paint from accidental contact from the hood as it is being un-bolted and removed.
...Scribe or paint alignment marks around the heads of the hood bolts before removal, as this helps make proper re-installation and alignment much easier.
...Disconnect any wiring harness or hoses that will interfere with the hood removal.
...Have an assistant support the weight of the hood as you remove the bolts. Be very careful to avoid damage to the hood or body if the hood suddenly comes loose as the bolts are removed.
...Remove the hood, being careful to place it in a safe place, and protect the areas that contact the ground from paint chips or other damage. Be sure to thread the bolts back into their holes in the hood, so these special bolts won't get mis-placed.

Shifter & Boot Removal...
...Phillips & regular screwdrivers
...10mm socket , ratchet, & 6?extension
...Clean rag
...While you are still nice and clean, now is a good time to get things ready inside. Remove any screws in the plastic trim around the boot, then carefully pry the plastic cover off to reveal the inner rubber boot and attaching screws. After the screws are removed and the rubber boot carefully pried loose and pulled up, the (4) shifter retaining plate screws can be removed with the 10mm socket, ratchet, and extension. Have a rag handy as the shifter pulls free, so that the oily bottom of the shifter?s inner workings can be wrapped to prevent dripping oil on your nice clean carpets & interior.

Remove The Seats...

Disconnect The Throttle Cable...
...The throttle cable should be dis-connected from the throttle pedal, so thet the cable will be free to removed from the engine compartment side of the firewall.

Disconnect The Clutch Master Cylinder...
...Needle Nose Pliers
...Again, while you are inside the car and relatively clean, it?s a good time to go up under the dash to dis-connect the clutch master cylinder?s pushrod clevise from the brake pedal. Simple removal of the pin is all that?s required.

Tagging The Electrical System...
...Tags (or masking tape) & a Marking Pen
...The connectors of primary importance are the following:
...Starter...
...Alternator...
...Water Temp Sender...the small sending unit located on the driver's side of the rear housing, just below the rotary engine's oil filter.
...Oil Pressure Sender...the large sending unit located on the driver's side of the rear housing, just below the rotary engine's oil filter.
...Oil Level Sensor...located in the rotary engine's oil pan.
...AC Compressor Clutch...
...Coolant Level Sensor...located in the top tank of the RX-7 radiator.
...Cooling Fans...


Misc Underbody & Exhaust Removal...
...12mm socket
...10mm socket
...First thing to remove is the (3) aluminum crossbraces (12mm socket) attached across the bottom of the transmission tunnel, and the shields (10mm socket) attached to them.
...Disconnect the harness to the oxygen sensor, as well as the ground strap to the catalytic converter.
...Disconnect the harness connectors attached to the transmisson for the reverse lights & gear position sensors. Automatic equipped cars will also have cooling lines, as well as undercar shift linkage to remove.
...All the exhaust system can be removed between the Turbos and the rear axle. The bolts/nuts are often very difficult to remove, so be sure to use 6 point sockets and wrenches to reduce the possibility of rounding off the hex. The penetrating oil applied earlier will greatly reduce the risk, but a little extra caution should still be exercised.
...After all the bolts are removed, the pipes can be pulled from their rubber hangers. A little twisting and tugging is all it takes to pull the rubber over the expanded head of it's mounting stud.


Prepping The Engine/Trans For Removal...
...Before the driveline is removed, be sure to drain the oil from the engine & transmission. This will prevent a big mess later when the engine/trans are pulled as a unit.
...Remove the driveline.
...Remove the underbody cover from under the radiator/oil cooler.
...Remove the engine's oil cooler lines.
...Remove the lower radiator hose.
...Remove the nuts & washers from the engine mounts at the subframe.


Removing The Power Plant Frame (PPF)...
...Support the rear of the transmission with a floor jack.
...There are (4) vertical studs & nuts (22mm socket / 6?extension) that attach the PPF to the transmission, and (4) vertical studs & nuts (22mm socket / 6? extension) as well as (1) horizontal bolt (22mm socket) attaching the PPF to the rear differential housing. Before removing any of these bolts altogether, they should all be ?broken loose? first, as they are very tight.
...Remove the (4) bolts that attach the PPF to the transmission. When the last bolt is removed, the front of the PPF can be lowered to relieve the weight of the nose of the differential.
...Remove the horizontal bolt from the lower right side of the PPF's rear attachment points.
...Now the rear (4) vertical nuts can be removed. The PPF can now be lowered and removed.
...Of the (4) vertical studs that held the PPF to the rear differential, loosen the front upper pressed-in stud, using moderate blows from a hammer to the smaller pilot portion of the threaded end. Remove and save the stud for later use. The rear upper stud can be left in place. The (2) lower studs are threaded into the bottom of the differential housing. Thread (2) of the nuts onto one of the studs, with the large flat areas of the nuts facing each other. Tighten the nuts against each other using (2) 22mm wrenches, with enough force so that the studs can be removed from the differential housing by using a wrench on the upper nut, and turning the stud out. Repeat for removal of the other lower stud.


Removing The Engine/Trans...
...Follow the proceedures set forth in the RX-7's shop manual.

What To Save Off Of The Engine/Trans...
...You will want to remove the following for re-use later:
...Temp sender
...Oil pressure sender
...PS pump (dis-connect the hoses at the steering rack)

Removing Un-needed Underhood Wiring & Misc...
...The entire ECU and ECU/engine harness can be removed. Be sure not to disturb the wiring for the wipers, cruise control, and ABS systems.

Steering Rack Preparations...
...Remove the shield over the steering column u-joint.
...Remove the bolts that secure the intermediate steering shaft between the column and rack.
...Remove the (4) bolts (14mm socket w/6" extension) that attach the steering rack to the engine subframe. The rack can now be pulled loose, moved forward, and temporarily supported out of the way by hanging it with wire.


Removing The Stock Rotary Engine Subframe...
...Remove the front wheels & tires.
...Support the lower control arm at it's inner end with a floor jack.
...Remove the lower control arm's inner pivot bolts, both front and rear.
...Lower the control arm from the subframe.
...Support the lower control arm with blocks.
...Repeat for the other side.
...Support the subframe with a floor jack.
...Remove the (6) nuts & bolts attaching the subframe to the RX-7's chassis.
...Carefully lower, remove the subframe. It will not be re-used.


Firewall "Lip" Modification...
...Fold down or remove the center 8" portion of the protruding lip on the face of the firewall. It is far better/easier to do a nice job now than to do a hack job later with the engine halfway in the car.

Firewall Holes for V8 Harness...
...Make a simple cardboard template of the size/shape required using your donor car's harness hole as a guide. Modify your RX-7's existing hole to match for an OEM quality firewall grommet fit.

Enlarge Existing Firewall Hole for Clutch Master Cylinder (T-56 Only)...
The 1" bore clutch master cyl uses a larger diameter pilot and rubber boot, requiring a larger 1-3/8" hole in the firewall for proper installation. Various methods of enlargement have been used...Dremel tool, die grinder, rotary file or unibit in a hand drill, etc...if you elect to use a plasma cutter, be sure to remove the flammable carpeting, backing, etc before proceeding.
...NOTE-...An alternate method some use to get around this task is to simply space the master cyl away from the firewall about 3/8". If you elect to go this route, be sure to seal the area well to keep engine compartment fumes and heat out of your passenger cabin. If you use this method, you will not be able to mount the master cylinder's protective rubber boot.

Extra Chassis Bracket Removal...
...There are 2 accessory mounting brackets (one on each side) just forward of the RX-7's spring towers that are attached to the lower chassis rails. These brackets protrude into the engine bay quite a bit, and can be quite a nuisance later on with the V8 in the car. It is much easier to remove them now. These two brackets are spot welded in place, and are easily removed with a "spot weld removal bit" for a hand drill. Be sure to drill a small 1/16" hole completely thru the center of the spot welds first to properly guide the bit. Remove the spot weld with the removal bit, progressing down just far enough to remove the bracket with a twisting motion. Grind down any remaining spot weld.

Power Steering Cooling Loop Removal...
...Although this sounds like a bad thing, it is actually quite common to remove the RX-7's power steering cooling loop to simplify plumbing. Most end up removing it at some point for convienance, and it's easier to do it now. Seldom is the loop re-installed. If you would like to retain the PS fluid cooling capabilities, an aux fin type cooler can be easily added later, but few bother.

Enlarge Forward Edge of Shifter Hole (T56 only)...
...While the transmission is out, now is the time to save yourself some work later on by extending the shifter hole forward by 1-1/4". This will help ensure full gear engagement and help prevent your T56 from popping out of gear.

Pressure Washing The Engine Compartment...
...On your way back from the AC shop, it?s a good idea to stop by the car wash and give the underhood area a good, thorough pressure washing. You would be surprised at how much easier and more enjoyable the job will be when you can actually see what you?re working on.

Insulate the Transmission Tunnel...
...If you live in a climate that requires extensive use of air conditioning, then this this will be time well spent. The RX-7's exhaust routing can cause it's transmission tunnel to become quite hot. Installing some insulation such as DynoMat will make that trip across Death Valley much more enjoyable.

Pre-Assembly Cleaning / Detailing Of The Engine Compartment...
...Now's the time to clean all those areas you couldn?t get to with the pressure washer earlier. Most any cleaner/de-greaser can be used. We use a product like Simple Green, applied by spraying, followed up with scrubbing with a nylon bristle brush, wiped off with rags. This won?t take long if you did a good job with the pressure washer earlier.

Engine Bay Paint / Detail / Touch-up...
...Do it now, it will never be easier. Be sure to check for corrosion in the areas under the RX-7's battery and master cylinders. If rust is present, be sure to treat it with a product such as Loctite's "Extend" that converts the rust to a stable, hard surface that is ready for paint.


Next page....

1....Introduction....

2....Considerations & Requirements....

3....Getting Started....

4....Engine / Transmission Installation....

5....Exhaust / Throttle Cable / Accessory Drive / Pulleys....

6....Cooling / Fuel Systems....

7....RX-7 Wiring Harness Connector ID and Circuit Locations....

8....Electrical System Modifications By Circuit....

9....Start-up / Troubleshooting....

10....Upgrades....

Back to 3rd gen Conversion Page....

Granny's Speed Shop Homepage....