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I’m excited to finally post this thread as my build has been progressing slowly since the rear apex seal in the Renesis failed back in 2017. It did limp me home for which I’m grateful for, I don’t think I will ever forget the sound/feel of running on one rotor or the feeling of disappointment that my 40K reman that I had installed only two years prior was kaput. I had been so sure that the BHR coil kit, Sohn adapter kit, BHR catless midpipe and a tune from Mazdamaniac was the recipe for a reliable 100K engine. Oh, how I was wrong, possibly more to do with the fact that I chose a remain (even with the brand-new rotor housing). I will explain more about that with detailed pictures later.
Since that time, I have been planning and collecting the necessary parts for a REW swap. I’ve also undertaken little custom projects as well.
A little about myself before the details. I don’t consider myself knowledgeable or particularly skilled with anything necessary to do this build on my own. This entire project is a first time for me. I have been learning so much here on rx8club about the car and all the caveats therein. I’m sure you have all noticed my post inquiring for more information and sounding noobish and that’s why.
I’m thankful my wife allowed me to get an rx8 back in 2003 and for friends along the way who introduced me to twisty roads in Arkansas and even our very own gem of a road course here in Hallett Oklahoma. Even after being bit by the Rotary and Turn Fast bug, it’s taken forever for this build to move forward, mainly due to other financial goals and family priorities, which if I might say are always more important. I thank the LORD for them every day.
My specific goals for this car (2006 Shinka which I acquired at 60K-3rd owner) build is mainly for a track toy at Hallett Motor Racing Circuit which is a 1.8-mile, 10 turn Road Racing course in the rolling Osage Hills of North Eastern Oklahoma. I’m not limited by any class rules. I have driven a little SCCA and would not be opposed to returning to that at some point. I fully expect to meet many challenges and I welcome criticism/input from all you fellow club members.
Yesterday I installed the rebuilt REW engine and Frankenstein transmission into my car and tightened everything down. Of course, it did require modification of the Beatrush transmission brace brackets but after that came the feeling of accomplishment until I realized that I probably will need to yank it all out for turbo manifold and downpipe construction.
Thus commences 4 year photo dump and catch up to current day.
Clearly Apex seal failure.
After Renesis engine removal.
My son.
There is the culprit.
So upon further investigation??? What is lodged into the coolant passages of this unopened Renesis reman...that might imped the coolant capabilities of the engine.
As if one is not enough, here is another...
Gathering parts...
Modification of rear stat gear and front cover modifications.
Last edited by Warrior777; 02-15-2021 at 01:43 PM.
Reason: Update
Assembly of the engine. I used rx8 stat gears and eccentric shaft. Oem Mazda side seals, Atkins Apex seals and Atkins soils corner seals. Turblown stud kit. Oem dowel pins. Had custom oil pan made by Built2apex that will use rx8 pick up tube. Also had to use an extra spacer as well as rx7 hub bolt and I think rx7 key.
Last edited by Warrior777; 02-15-2021 at 02:00 PM.
The front cover bypass mod isn't really necessary. My current cover has no bypass and the motor has survived hundreds amd hundreds of pulls and thousands of miles without it. Not criticism of what you have done, just letting anyone out there who may be reading this know....
Good luck ahead and I look forward to the updates....
If you need a cheap s362sxe with 3 inch machined flange let me know. It hits hard, ask my last trans.
What trans are you using and turbo? All looks so good!
I'm using the FD 5 speed gears, the rx8 5 speed bell housing and tail shaft. Everything bolts right up.
I plan on using an IW EFR 8374. 92 a/r is it? Have not purchased the turbo yet. I plan on at least 3 inch or even 3.5 inch down pipe and still have an exotic speed rII titan cat back.
I had a rx8 Adaptronic select ECU but sold that and will buy the new modular.
Will have to wait to buy these parts until after we pay off the wife's Honda Odyssey.
Last edited by Warrior777; 02-18-2021 at 09:20 AM.
I remember that from your build thread. Thanks for the advice. It is necessary to continue use of the OMP which is not necessary and can always be deleted. I'm going to try my best to save it. This will result in longer exhaust runners as there is no way to do a low mount turbo placement without cutting into the frame of the car with the size of turbo I'm using. Or so I have estimated.
Yea this would probably be the way to go. I'm not at all familiar with what is required to do this and have read some issues that arise when changed to the EWP, can't remember specifics as the moment. I'm convincible.
I plan not to take the traditional air to air intercooler route but would like to do a air to water intercooler. I have been gathering information. My buddy put me on to the frozenboost.com website. I've had others tell me to stay away from the cheap stuff.
Here is my heavy idea of a trunk battery mount that will allow use of a rear strut tower brace. Built for a yellow top but now thinking I should have gone with a lighter battery.
Last edited by Warrior777; 02-18-2021 at 09:21 AM.
So here is my idea for cooling: water to air something like this photo
This is the conversation I had with the owner on Facebook when I happened to run across his post ( it did not give me much hope)
So what do you guys know about water to air and what advice can you give? Any ideas on how to make a successful system that can handle 10-20 laps at road course 20 minute runs? From what I understand, a big pump, large enough capacity and big enough lines should do the trick. For the record I really want nice and stable air intake temps, not to worried if they are 10 degrees higher than an air to air setup. I think another important thing would be engine bay heat management. Probably will eventually go E85 as well...
Last edited by Warrior777; 02-19-2021 at 12:27 PM.
The 8374 will fit in a low mount and it won’t require cutting the chassis.
You might be thinking with a Renesis engine and the only issue there is nobody is willing to do the non-chassis cutting mods to get it in. It’s a lot easier with the REW setup.
.
The 8374 will fit in a low mount and it won’t require cutting the chassis.
You might be thinking with a Renesis engine and the only issue there is nobody is willing to do the non-chassis cutting mods to get it in. It’s a lot easier with the REW setup.
.
Well I think more of the issue is with the rx8 front cover coolant passages and the omp with sohn adapter. I will see when I get the turbo. If I can fit the low mount that would be ideal. I may just ditch the omp and do the EWP like you suggested who knows.
I know we used different front covers, so maybe that's the difference, but I have a 9174iwg (same dimensions as 8374) low mounted with a custom Manifold. I also have the stock RX7 OMP in place and we had it functioning with the Adaptronic modular so I'm certain it should be no issue for the Rx8 OMP. I've ended up deleteing the OMP and going full pre-mix anyways also. Shawn Christenson provided all the info I need to get that functioning but I imagine the Rx8 OMP will be a direct plug in?
I'm willing to bet even with the Rx8 front cover, if you were to delete the OMP a low mount would fit but I'm uncertain it would with the OMP in place. With the Rx7 OMP my turbo compressor housing had roughly 1/4" clearance from the OMP, its definitely tight and I'm not sure of the actual dimensional difference with the Rx8 components there instead.
Good luck with the build! At the rate my engine builder is moving maybe we'll have our cars up and running at the same time!!!
I know we used different front covers, so maybe that's the difference, but I have a 9174iwg (same dimensions as 8374) low mounted with a custom Manifold. I also have the stock RX7 OMP in place and we had it functioning with the Adaptronic modular so I'm certain it should be no issue for the Rx8 OMP. I've ended up deleteing the OMP and going full pre-mix anyways also. Shawn Christenson provided all the info I need to get that functioning but I imagine the Rx8 OMP will be a direct plug in?
I'm willing to bet even with the Rx8 front cover, if you were to delete the OMP a low mount would fit but I'm uncertain it would with the OMP in place. With the Rx7 OMP my turbo compressor housing had roughly 1/4" clearance from the OMP, its definitely tight and I'm not sure of the actual dimensional difference with the Rx8 components there instead.
Good luck with the build! At the rate my engine builder is moving maybe we'll have our cars up and running at the same time!!!
I appreciate the info. I realize the OMP is the major obstacle, it seems that there may be room to get this done but it will be real tight. I remember first seeing your manifold on your thread, it's a work of art.
When I first planned out this build I had the Adaptronic plug and play ECU which required the OMP to be plugged in but now that I've sold it in favor of purchasing the modular version I don't think having the OMP plugged in is required. My train of thought this whole time has been, if I have to plug it in, I'm going to use it. I would still like to use it but I don't know how much I'm willing to sacrifice for it.
Thanks for the good wishes. I hope I don't win the award for longest swap duration. One day I will buy the expensive stuff maybe sooner as my wife just got a huge monthly raise, now she makes more than me...I'm not complaining.
Last edited by Warrior777; 02-24-2021 at 12:15 PM.
I appreciate the info. I realize the OMP is the major obstacle, it seems that there may be room to get this done but it will be real tight. I remember first seeing your manifold on your thread, it's a work of art.
When I first planned out this build I had the Adaptronic plug and play ECU which required the OMP to be plugged in but now that I've sold it in favor of purchasing the modular version I don't think having the OMP plugged in is required. My train of thought this whole time has been, if I have to plug it in, I'm going to use it. I would still like to use it but I don't know how much I'm willing to sacrifice for it.
Thanks for the good wishes. I hope I don't win the award for longest swap duration. One day I will buy the expensive stuff maybe sooner as my wife just got a huge monthly raise, now she makes more than me...I'm not complaining.
One other thing to consider since you are torn about it; one downside I'm noticing right now (only because of the issues I was having) is that it is extremely difficult (not even 100% sure if it's possible) to pull the turbo, ex. manifold, and LIM off with the engine in place. I imagine it can be done if the engine mounts are loosened and the engine pushed over a bit, but just something to think about. Having the turbo placement a little bit higher (above the frame rail) will make any sort of maintenance on those items much easier. With that being said, speaking in particular to my build the EFR turbo's are well known for their robustness, so I don't anticipate having to remove the turbo/manifold often if at all. I anticipate the turbo to last just as long, or longer, than the engine and I wanted the responsiveness of a low mount. The coolant ports, oil fittings, and actuator are all accessible (again very tight fitting) with it in place so no issues there. With a different turbo this may not even be an issue, the EFR's are generally a bit more bulky than other brands.
Originally Posted by Warrior777
The shifter barely fits but I think it’s going to work. Have you guys had better fitment? Or is this to be expected with the 5speed?
Hmm I'd like to know more about this from someone who has used the RX8 5 speed, I was under the impression that it should fit exactly like the 6 speed. Does the modified Rx7 trans you use have slightly different dimensions than the Rx8 trans? I thought only difference was Bell house and tail piece as you mentioned you swapped out.
Last edited by RotaryMachineRx; 02-25-2021 at 12:09 PM.
Just so we are all in the same page, I’m using rx7 FD 5 speed gears, rx8 5 speed bell housing and rx8 5 speed tail shaft.
The shifter seems to be shifted about 1 inch toward the driver.
What are you using for motor mounts? The shift is likely due to a slight rotation of the engine and thats likely the way the mounts are situated. My 5 speed sits like stock in the center
Just so we are all in the same page, I’m using rx7 FD 5 speed gears, rx8 5 speed bell housing and rx8 5 speed tail shaft.
The shifter seems to be shifted about 1 inch toward the driver.
I guess what I was getting at is..... Is that exactly what the Rx8 5 speed is, or is the gearbox slightly different dimensions?
I have to agree with Dan though, if it is sitting off to the left there must be some sort of alignment issue. I figured you just meant it was slightly off front to back, didnt look at the picture close enough
I’m using the Nicon rotary swap mount. It’s possible the alignment may be off due to the fact I’m using a beat rush transmission brace and it need modification to fit. I will take some more pictures.
it does look off center in your pics, but perhaps a bit hard to be sure how much of that might be from the camera angle
without a doubt it dimensionally should be the same regardless of which trans center section is used between the FD3 and RX8, but the one thing to note is the RX8 box has multi-synchros and other upgrades the FD box doesn’t. I’m curious on how you obtained the RX8 bell & tail housings, but not the center box section?
One thing I noticed when switching from an rx8 5 speed to a frankensteined FD trans is that the angle of the shifter was more towards the e-brake handle, which would be better for a RHD car. In 5th gear I was only about a half inch from e-brake (don't remember it so close that I scrape my pinky on it while shifting). Alignment was centered though. Solution was to bend the e-brake handle another half inch towards the passenger seat. I'm not sure why this happened except for the alignment/bolt hole locations are angled slightly different between the two boxes..... Overall the rx8 box shifted a bit smoother, 2nd gear seems to catch on the FD box for a fraction of a second while going into gear while normally driving. Was a junkyard trans when I got it and the previous owner had a 3 puck clutch on it so I doubt it was babied much.
Last edited by strokercharged95gt; 03-02-2021 at 06:55 AM.
Well I purchased the trans from a friend who had both an FD box and a rx8 5 speed transmission, he had similar plans as I did but decided to sell all his stuff. He did the work himself and decided to use the Rx7 gears instead of the rx8 gears. I thought it was interesting he did that, but by the time I purchased the transmission from him he had already sold the rx8 5 speed gears. I suppose I should verify I actually have all the correct components. Looking at how close the slave cylinder is to the driver side transmission tunnel even with it not being bolted down makes me think the engine mounts are shifted some how.
02-12-2021, 02:58 PM
. Overall the rx8 box shifted a bit smoother, 2nd gear seems to catch on the FD box for a fraction of a second while going into gear while normally driving. Was a junkyard trans when I got it and the previous owner had a 3 puck clutch on it so I doubt it was babied much.