There are a number of threads around the internet about Andrew Keisler’s LFX swap kit. What makes this one different is that I purchased the kit to install myself. If that interests you, read on. If you want to know how the resulting car handles, read the results in other posts.
Andrew’s charge for building the kit into your car (or a car he buys for you) is very reasonable and unless you have a specific reason why you want to do the swap yourself, it is well worth considering. As an engineer, I wanted to get familiar with every aspect of my car so doing the conversion myself was very appealing. However, I’m not sure it was the right decision in the end. Read on.
About me:
- I have almost zero fabrication skills. So, any kit would need to be basically a bolt in operation.
- I have very limited diagnostic skills mechanically and almost zero electrically.
- I do have an enclosed garage and a lift, which makes things much easier.
About the roller I bought:
It is a 2005 base manual transmission, but it had been sitting for a while not running. Based on my project and Andrew’s experience, it seems many RX8 parts give up the ghost while sitting for extended periods. The resulting mechanics fees (see point 2 about me) to diagnose and fix these issues added up to more than the increased amount I’d have paid for a running donor car. I had issues with the fuel pump, crank angle sensor, electronic power steering, console faceplate and a few others. And it’s taken a long time to find and fix all of these issues. That has been the only negative experience I’ve had with the swap. So, a note to the wise.
About Andrew and Keisler Automation:
As others have said, working with Andrew is a delight. He’s knowledgeable, responsive, and willing to help in any way he can. Before I committed to the purchase, he and I swapped a number of emails and a phone call or two discussing the kit and my goals. I also visited him and drove his car which absolutely sold me on doing this swap. Throughout the process he has answered dozens of emails from me; some with questions for installing the kit, some asking for recommendations for other work I was doing on the car, and some for troubleshooting problems with the RX8 equipment (see the description of the roller).
The kit:
It’s hard to imagine a more complete kit. Everything needed to complete the swap is included, even the fasteners that would be easy to just list and make the installer buy. Not only are they included, but they are mostly ziptied onto the specific parts they go with. In other cases, they are in bags that are labelled. Add to that the 15 instructional videos that detail essentially the entire installation process and you have a swap kit that just about anyone can complete. I am the proof. This is definitely the most comprehensive set of instructions I have ever seen for anything. Here are some pics of the kit contents. Look for the zip ties holding nuts or bolts to their respective parts.
The installation:
I can’t imagine that there could be an easier swap install than this. It’s still a major project, but everything in the kit goes together just as Andrew and the instructional videos describe. Overall, I think I invested about 80 hours in the swap, and I did it by myself but for a few points where I simply needed an extra set of hands. I’d watch the video for one action, go do it, and repeat. In addition to installing the kit, I also took the opportunity to clean the entire chassis and interior, replace brake rotors, calipers, and flexible brake lines. I also installed a trailer hitch for a track trailer.
There were zero significant kit related installation issues! Except for a couple minor fitment issues noted below on part of the track option, everything just fits as it should. On the rear diff install, the most fabrication needed is to drill holes for the rear carrier (diff) using the new mounting plate as a guide, cutting the aluminum ear off the GM diff with a hacksaw, and removing the OEM diff bushings. In the engine bay, you will need to drill a hole with a hole saw, drill out a few spot welds, cut out part of the hood inner liner, enlarge the hole for the clutch master cylinder and make a very minor modification to the ECU box. I also purchased the track kit which added the need to make some modifications to the front engine bay wall to allow radiator hoses to pass through. There are a few other holes to drill for the battery relocation, etc. That’s it. No specialty tools required either.
All of the electrical wiring modifications are included in the kit which is a huge relief to folks like me that can unbolt and bolt parts but wires are just a language I don’t speak.
You need to arrange for your own exhaust. I reused the stock muffler and had a local shop fabricate the rest.
The minor issues I encountered:
I purchased track package and kept AC. This caused a minor interference between the AC line and the engine undertray. I cut a small slot to allow the AC pipe to clear. It protrudes less than an inch.
The track package also includes a replacement radiator that Andrew sources. It had minor fitment issues that are common with aftermarket parts like this but was useable with some minor persuasion.
On one of my trips to the local mechanic for diagnosis, they found a weak ground from engine to chassis. They added a ground cable part no. A15-1L as shown.
The result:
The car is awesome! I have some body work to do and a list of minor things to fix on the original car, etc. but that is part of being an enthusiast. The kit has done exactly what it is designed and marketed to do. The car has great power, but not too much. There’s torque everywhere and the car seems quite stiff and stable. I’m still on the OEM suspension and the shocks look original so I’m surprised at how well controlled the chassis is with 129k miles on it. I will probably upgrade the suspension next year.
The car is currently fully stock except for the kit and the trailer hitch. Weight is 1590 front and 1442 rear with all fluids full including fuel. Corner cross weights on the stock suspension are 1524 and 1508. It feels very balanced.
The car is loud in the cabin. Most of this seems to be a lack of factory sound reduction materials. I may add sound deadening in the future.
The MV5 transmission is very notchy. It takes some getting used to after years of driving my Mazdaspeed6 with its very light shifter.
I used a 3.45 rear end and now recommend that the 3.27 is more than adequate for all street driving. The 3.45 and 3.91 make 1st gear almost worthless unless you insist on drag racing.
Overall, I’m very pleased with the result and look forward to spirited driving and track days once the weather warms.
Conclusion:
If you want an awesome chassis with a bulletproof driveline, an RX8 LFX may be just the ticket and the Keisler swap kit is the best thing you can do to make it happen.
Other hints and tips:
It’s really helpful to have internet access in your workspace so you can access the videos easily. I was constantly watching a section, then replaying to make sure I understood how to do each step. Then I’d do it and repeat.
Andrew recommends a lift table to lower and raise the subframes when it’s time. If you don’t have access to one, the Harbor Freight 1000 lb unit is what he recommends (compare this cost to the cost for Andrew to do the entire install). You’ll need to leave the vertical handle disconnected to allow clearance for the subframes. Also, I found the table to be too small to do the differential swap as shown in the video, so I used the lift table to lower the subframe, then put a pallet on my engine crane legs and lifted the subframe from the lift table to the pallet for the swap and then back to the lift table for reinstallation.
When installing the new bushing in the differential, take 5-10 minutes to file a small chamfer on the leading edge. It will make the bushing slide in much easier.
Axle seals shown to be replaced in the video are not necessary to be replaced and are not included in the kit. If you want to replace for peace of mind, the part number is AC Delco 291338.
The videos didn’t cover the parts to harvest from the RX8 engine and the installation of the harmonic damper and Mazda crank angle sensor. You’ll want to take the coolant temperature sensor, the oil pressure sensor, the crankshaft position sensor, and the crankshaft position wheel from the OEM engine (or buy replacements, the OEM crank position and oil pressure sensors didn’t work in my case).
When enlarging the firewall hole for the new clutch master cylinder, I used a marker to color out 1/8”. Then a tungsten carbide cutter on a Dremel to ream out the hole. This worked very well.
When cutting the welds at the front subframe locating bolts, I used a Dremel with a cutting wheel to cut most of the way through the welds. Once the bolts were out, I used a grinding stone in the Dremel to flatten the remaining weld material most of the way.
When loading the engine/tranny assembly onto the lift table for installation, make sure the handle end is at the front of the engine and that the passenger exhaust pipe clears the lift table.
I found that 1/2” of washers under the rear transmission mount was the right amount for hood clearance and for the rest of the driveline.
When attaching the engine to the engine stand, set the center of rotation about 6 inches above the crank for best balance, expect some residual oil to drip out after removing the oil pan and returning to upright position.
The coolant reservoir is full when the level is about 1.5 inches below the fill line cold. Otherwise you’ll be trying to figure out where the coolant on the floor is coming from.
Enjoy!
