The RX8 LGX swap is officially starting!

I was going to “document” this one on the road racing forum I belong to, but since that forum is private, it would be a pain trying to deal with the content and in case anyone wanted to refer to it. So bringing back this domain with a simple blog style, so I can drop all the updates here. For my benefit, as I wanted to have notes and details, and others, if someone else is going to attempt this swap too.

So let’s get started. I bought this 2010 midlife crisis RX8 with the intent of swapping an LFX motor into it using Keisler Automation’s LFX kit. A few track days and a couple of years of driving it to mountain bike trailheads and I’m finally pulling the trigger.

Since I bought it though, a few things have changed. The LFX wiring harnesses are a huge pain to get, and the idea of an LGX swap with the 10 speed auto transmission came to be. The LGX is the updated 2020+ version of the Camaro V6 with better airflow, a bit more power, and a better setup to go into the RX8. The motor sits further back, lower, and more importantly, has an option for the amazing 10L60 10 speed auto transmission. That’s what I really wanted in the first place anyways, as I wanted 100ms gear shifts and paddle shifters. I ordered most of the LGX swap from Andrew, and then I found someone on the LFX swap FB group selling the rest of the auto swap kit (INCLUDING WIRING!) and a transmission, so I jumped on that as well. Andrew hasn’t gotten the LGX swap dialed yet, he still isn’t making “production” wiring harnesses for it, but he did make a few prototypes and this one for sale, was one of them. Let’s Go! Some car-part.com searching started for an engine, and I found a pristine 10k mile engine from a 2024 Camaro, so that has also made its way to the shop where I’ll be doing the swap.

While I was waiting for parts to arrive, I also ordered an 80mm throttle body from a Silverado, as well as a Soler Engineering adapter, as I read that’s a good air flow upgrade for the LGX. A few minutes with a die grinder and a flap wheel, and I had a nicely ported/polished throttle body that’s ready to go. After I did that, Andrew mentioned that the adapter might clock the throttle body connector so that it interferes with the hood, so we’ll have to watch out for that. If it does, I’ll port the OEM throttle body instead and put that on. But that’s a much later task.

I officially started on the swap yesterday by cleaning up the rental shop to get ready to work and getting a seat test fitted. I found a nice Corbeau seat on FB Marketplace and bought a new RX8 specific bracket from Summit Racing so wanted to try that, as I’ve heard that seat height can be a problem. With this bracket and the bottom mount seat, it’s super low, which is perfect. Done. I also pulled the OEM steering wheel, as I had to get a new wheel with paddle shifters. Lastly, I started pulling stuff from the engine bay. Got as far as getting the intake and a few other misc pieces out.

Next work session I’ll get the bumper pulled and more stuff out from the engine bay. The intent of this engine removal is to pull the entire front subframe down from the bottom, so everything in the engine bay has to get disconnected, then the subframe bolts loosened, and I’ll pick the front of the car with an engine hoist and slide everything out.