so now that she likes it, and assuming your going ahead with the swap, how long are you giving yourself to finish?
I don't know how long it will take to swap. I don't anticipate this swap being too bad because of the goals. I will say 3-6 months. Take that with a grain of salt, you know how these things go.
Right now I am going to move ahead with the 4G63 as my engine choice unless it runs into a roadblock like being too tall(remember the goal is +-275whp and auto trans, still be as much fun to drive as stock rx8). It is the engine I know the best and I already have several to use for fitment. I am going check to see if it could work with the stock mazda automatic 4spd transmission just for kicks (using a custom adapter plate). It may not, because the input shaft of the mazda trans may be position too high causing the 4G63 to set too high in the car. My plan if the mazda trans cannot be used is to buy the Bushcur GM auto adapter plate for the 4G63 and use a 4L60E trans. So my immediate to do list:
1. Pull rotary (weigh it without accessories for posterity)
2. Check 4G63 fit to stock rx8 auto transmission (steering rack, hood clearance, height of trans input shaft, bellhousing adapter possibility)
3. Pull 4spd mazda automatic trans (weigh it with converter)
4. Check 4G63/4L60E fit (steering rack, hood clearance)
5. Weigh 4G63 without accessories for comparison
6. Weigh 4L60E with converter for comparison
Once those tasks are complete I will actually know if I have a chance of using this combo for the swap or if I want to select a different combo. I need to grab a 4L60E off craigslist or borrow one from someone who is local for the fit test. Let me know if you are local (Colorado) and have one I could borrow for mock up.
Now we are down to the real question, when do I plan to pull that rotary out. I was planning to pull it this coming weekend. This is very tough because the car is running and driving, albeit on low power and low compression. I guess if I pull it now before an apex seal breaks and inspect the rotors and housings, maybe I can sell it as a rebuildable core. If the irons, rotors and housings are all in reusable shape I am going to be tempted to rebuild the rotary and throw it right back in because I have never rebuilt one before and the idea is very interesting to me. So I am going to need to some persuasion from you guys to stay on track with a 4cyl turbo swap. For the price of doing a nice rotary rebuild if all parts are reusable (I'm calling that price $2500) I can build a nice stockish 4G63 with small turbo and purchase a 4L60E and a computer to run the transmission. I already have a couple spare megasquirt computers to run the 4G63.
Of course I want to start this swap like every other ambitious person and say that I will be able to retain the stock steering rack, ABS, DSC, TSC and drive by wire TB so that the stability control would all work with the new swap. However, I am not going to stall and get hung up on these. I am willing to quickly ditch the steering rack and lose DSC/TSC to get this going. From a technical standpoint, I am interested to see if this could all be maintained and integrate with a new engine. I know a couple people on the forums claim they have maintained all of this, but they somehow do not list any detail or show videos of these systems working on the swap. I have been thrashing the car a bit on the dirt and pavement to see how all of these systems work together to control the TB, apply the ABS and I assume change the sensitivity of the steering. I can imagine retaining all the stock engine and trans sensors so the stock ECU works in the car. Then it still controls the electric TB on the new engine and megasquirt just sees a throttle position input. Now the DSC/TSC can still pull power from the new engine by controlling the TB like it use to. However, the new engines torque curve is different than the rotary. So, does this render the system useless or is it close enough that it still performs?? Yeah, you guys know that I will ponder all of this shit and then in the first five minutes of fitment decide to toss it all and get on with the swap. Mental masturbation
EDIT: I should mention that it is acceptable on this swap to have a reverse hood scoop of a couple inches to clear the timing gears of a 4 cylinder turbo engine.
