RX-8 13B-RE conversion!
 

Hello guys,

I figured I'd make a thread in this section since the RX-8 qualifies as "other rotary' and my previous plans of putting a 20B in the car have changed.

Here is my original post from the 20B section of the forum:
https://www.rx7club.com/20b-forum-95/20b-rx-8-conversion-about-damm-time-884787/

Since then I got rid of the BW S475 and the other 20B related stuff and the car sat for almost two years due to the fact that I went solo with my manufacturing business (quit my day job) and it pretty much took all of my time for the past year and a half.

Now that things are stable the new plans are as follows:

• 13B-RE Large Streetport (already have, need to Stud motor and change exhaust sleeves) - will adapt Renesis Front Cover to engine to allow all accessories and vehicle functions to work properly
• Turbonetics 72mm HPC Billet turbo, 1.00A/R Divided, F1 68mm wheel (ordered- interested in seeing what this does)
• 4" turbo back exhaust (exhaust is made but Downpipe used to be 3")
• Haltech Sprint RE
• Stainless Manifold by yours truly (parts ordered)
• Same E-85 dual Bosch 044 setup as before
• change to 2000cc secondaries and perhaps primaries as well

I'm looking for a reliable 500whp on E-85..might seem like this setup is overbuilt for what I want but would rather have that than the alternative.

So far I only have a few pics of the beginning of the process...:)

Will continue to update as I make progress.

Thanks for looking!

Chris

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Because the RX-8 engine is located so far into the firewall, no REW or BRE LIM will fit without forcing the UIM to interfere with the firewall. A good solution to this would be to get an Xcessive LIM but since I like to do things the hard way and I had a 20B LIM available I decided to try this...and it worked! :)

Now just need to clean it up...

Lets see here...
Attachment 718022

Hmmmhummm...
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Ooops...
http://i679.photobucket.com/albums/v...n/IMAG0565.jpg

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Not finished but you get the idea...one hole doesn't match from the LIM to the block (will need to drill) and I had to enlarge two holes on the 13B-RE UIM but all the ports lined up beautifully!
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And as I was trying to plan out how I would custom make engine mounts...I couldn't help but notice a similitude between the BRE and the Renesis...so I decided to give the Renesis mounts a try and they are close enough that I will definitely use them:

This was right off the bat with 0 issues...

Cheers!

Driver's side fits on all but one hole so I will just add support to both OEM BRE anchor points...
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Passenger's side...fit on all but one hole also but this one will be modified more heavily to allow the turbo manifold to route properly and make use of the OEM BRE anchor points...
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very interesting project.... keep up the good work

I like what you are doing, but I am not sure how I feel about the engine mount on a rotor housing instead of a plate.
Not to mention your exhaust manifold issues that will arise.

With your skill set, I would have figured you'd modify the RE mounts to fit inside the RX-8 Chassis.

BTW, that took some BIG BALLS to cut up that 20B Intake.
Glad it worked.

Good point...except that is exactly where the mount bolts up to in an RX-8, the housing. I put over 500whp through that mount in the renesis engine and never had issues with it. However, I will not use that mounting point, my plan is to use the mounting points from the RE engine to "bridge" over to the RX-8 mount so that I can cut that upper part that attaches to the housing and my turbo manifold will have clearance. I will post pics as I get further along the build and it will clarify alot.

About the 20b manifold...lets just say I had a "frog" in my throat as I was cutting through it with my band saw...kind of like when your highschool GF breaks up with you...lol

Best regards,

Chris

Here is a rough example of what the plan is for the mounts...

Chris

Passenger Mount Trim and reinforcement to RE mount points:
Attachment 718028

Driver Side Reinforcements to RE mount points:
Attachment 718029

Subscribed!

No big updates other than I received the pipe elbows for the manifold...goals for the manifold are:

• equal length to +/-0.5"
• 2" SS304 (Schedule 10)
• Dual 38mm Wastegates (fully divided)

Wastegates, Engine flange and T4 flange have been ordered...

Chris

Attachment 718030

So basically you did everything I did on my thread from 2009 on the RX8 club? Don't know what you were worried about the intake for(btw the top bolt on the intake for the first rotor ain't gonna work), I had already covered that back then. So seeing that you're gonig to use the same stock mounts your engine is going to sit exactly like mine. The oil filter pedestal also isn't going to work. But just wondering why you started a thread on the RX7 club instead of the RX8club?

I was not aware you had done a full documentation of every issue you ran into when swapping your 13B-RE, I haven't really been through your thread although now that you mention it, I will. From what I remember, it wasn't very detailed in the path you took to reach your goal. I had totally forgotten about your conversion, I was building my Renesis back then trying to show where it could be taken. Since then, I hadn't even thought about that thread until you brought it up. I never claimed that I was the first person to ever swap an 13B-RE engine into an RX-8, I have friends in PR that did this back in 2005-6, so what?

The direction I am taking this build is similar to what I did with the Renesis in the past, it is my personal car and therefore will have differences from any one elses build. Fabrication will be documented in pretty good detail. I posted it here because I frequent this site more often even though I don't post as much. I have been frequenting it from before I had an RX-8 and lived in PR. The world does not revolve around rx8club.com...you make it sound like I'm cheating or something...lol My original build thread was posted in the 20B section here because that is where I was headed. Now that I got tired of having the car sit un-touched (due to work/wedding) and my plans changed from 20b to 13b it was natural to do the thread here. I don't understand why you appear upset about this...

Everything I have posted so far here has been figured out on my own, if someone else got to the same conclusion in the past when doing their swap, more power to them. I am following my own path.

This is just a build thread about a build...simple

If I had to give credit to anyone it would be Roberto Gonzalez and "Galdi" from PR (El Psiquiatra) who I've been bouncing things off for years and has done more than a few of these type of swaps...

Chris

ps. I know about one hole not matching on the LIM and on the UIM, I mentioned it in my first post. I also know about the oil pedestal among other things...I own a manufacturing facility, I think I'll be able to handle it ;)

^ First off...If I misunderstood your intentions/demeanor I apologize...

Moving on to the build...this is the plan for the Driver's engine mount. It will get better fit before welding...;)

Chris

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Actually back then it was very detailed, and anyone who asks I send detailed pictures and instructions

No,, it just seemed more fitting to me I guess to see a RX8 conversion in the RX8club along with the other swaps.

Now why in the world would I be upset??? Hope your project goes well and finishes!

Actually I wasn't talking about the bolt to the LIM and UIM, but on the LIM to the block.

Actually, side engine mounts are superior to all other previous motor mounts. Here's my first and latest setup:

Awesome build! Subscribed!

I love it!

The renny is a good engine but if you what to make some real power and keep it some what reliable then a older turbo 13b is what's needed.....IMO.
But what do I know.

Very interesting project you have. The cosmo is definitely leaps and bounds better than the renisis engine in every aspect except emissions... With a 72mm turbo you should easily be able to break 600whp on e85. there's several people making 550+whp on 67mm turbos with the more restrictive rew motor.

Estevan, in what possible way could the renisis engine even be considered decent? You would be hard pressed to find a less reliable/problematic engine than the rx8 motor put into a production car. That motor ruined any good reputation the rotary had left...

^

The renesis is not that terrible of an engine in itself...I think its a situation where a misunderstood engine gets combined with a bunch of people that shouldn't own a rotary. Think of the majority of the people that own RX-7's and how different that is from the majority of people that own RX-8s. Mazda accomplished a goal, it wanted to sell the rotary to the masses and the RX-8 did just that...except that women that are used to a camry never check their oil and aren't expecting it to consume any and then they run it dry... people that are used to regular daily driver cars don't understand how important it is to warm up the engine..etc etc etc I could go on forever. The rotary engine is awesome but requires a degree of delicacy on part of the owner, everyone here knows that...most people that bought and RX-8 did not. What the renesis is Not is a run of the mill 4 cyl toyota engine...therefore it should be treated differently. I had plenty of fun with my renesis and accomplished a lot of firsts, first to 350, 400 and 500whp...first turbo bridgeport renesis...etc etc etc...Now I just want to go fast with no fuz and have nothing else to prove so Im swapping in an RE... originally I only pulled the Reni to swap in a 20B and then plans changed...otherwise I would've kept the Reni.

Quick update...

Flanges came in....both are SS :)

Attachment 718035

Very nice!

Ill be watching this one!

Nothing much other than I received the exhaust sleeves...the Engine has a large streetport but the exhaust sleeves are the original cosmo ones which are very restrictive so I got these...Thanks japan2la!

Today I will be working on the driver's engine mount a bit so I can test fit the engine in the car soon...then I can begin the manifold.

Attachment 718036

Cut Passenger's side Mount...milled lip off manifold flange to minimize how much it will stick out towards the mount.

The cardboard is representative of the Renesis OMP which will be in that area once I swap the Renesis front cover to the 13B-RE engine.

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Very good point on the average rx8 driver. There is a lot of women rx8 drivers around my area and they wouldn't even know that their car was rotary powered. Its irritating that Mazda took a major step backwards from rew to the reni in being able to make reliable power. Did you part out the reni setup?

Quick update

Got the front cover off the Renesis so I could see what I would be dealing with installing this cover onto a BRE front plate. On Wednesday I fly to Puerto Rico for a week for business but while there will visit a friend that has a rotary shop. He has succesfully installed the Renesis front cover onto REW/BRE engines and with a bit of modification has gotten the Renesis OMP etc working properly so it doesn't require premix. From talking to him I know there will be a bit of clearancing required to get the front cover on simply because on the renesis the front counterweight is sunk into the front plate and on earlier models the counterweight is out into the front cover. He also said something about drilling an oil passage or something...we'll see.

Here you can see the front cover off the engine
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Here you can clearly see how the front counterweight is sunk into the renesis plate
Attachment 718039

Another from a different angle.
Attachment 718040

I'm in !!
 

... hey, I think I should be included in this privileged credit list for my periodically once in a while 2 cents... :)