This has been on my mind the last couple days.
If someone were to get a hold of a '84-85 gsl-se and wanted to swap a renesis into it what would all have to be done to get it properly running.
They're both 13b engines, would the transmission and rear end have to be swapped? The engine harness needs to be taken from a rx8 and then spliced into the gsl-se harness. I just don't know the details involved.
It's been done before I know that but the build threads I've seen were 12a to 13b swaps not 13b to 13b.

 

A GSL-SE 13B is a very different creature than a Renesis. Other discussions that I have seen have compared transplanting a Renesis to transplanting a 20B: a very big deal with a big price tag, unless you can do all the work yourself (defined as experienced mechanic and fabricator).

With that said, I've always thought that the Renesis was the second most logical upgrade for a 1st gen. (The most logical is a 2nd gen 13B, like mine. Much less expensive.)

The biggest stumbling block, AFAIK, is engine control. If you do some searching, you'll find threads discussing that issue. If you can afford a Wolf ECU, I believe it can do the job, but that's very expensive.

You might try contacting PFS in Frederick, Maryland. They have done some work on upgrading RX-8s, which might give them insight into a 1st gen transplant.

 

getting the engine in the car doesn't seem so bad, getting the stock Rx8 ecu to control the engine is tough, as the Rx8 ecu controls a bunch of stuff in the car, and so it needs TONS of stuff hooked up.

the GSL-SE ecu won't run it, it can't control any of the intake valves, and it needs more injector, unless you want to limit your rpm to like 4000 or something.

that leaves you with the MoTeC/ Haltech/ etc which is fine.

i think its a good swap too, but aftermarket ecu means its not really cheap and easy anymore

 

Im wondering what they use for engine management in the Star Mazda race series. Those open wheelers ran completely stock RENESIS engines with a fully operating stock intake manifold and no emmissions devices. Being that all the power plants were supplied by Mazda, I can only assume that they also supplied the engine management as well. Now the question is did they use some crazy expensive MoTec or similar, or did Mazda make a "cracked" factory ecu which has the CAN Bus/emmsisions delete?




*edit* found the info

they run a "MoTeC encrypted ECU including rev limiter, pit speed limiter, traction control, fuel trim" ...now i just have to get my hands on one of these

 

Just curious what your benefits of the renisis are over a 2g 13b/ TII motor? Unless its for better emissions/ mileage? Just curious. Thx! Not sur if he would know but ask Elliot at Turblown.. He does a lot or rx8 tuning and custom turbo stuff...

 

I believe the renesis was said to have 200+ bhp stock n/a, but other than that I couldn't really tell you any differences. I have heard that its almost impossible for a shade tree mechanic to work on a renesis though...way too many electrical gizmos controlling everything.

The bhp alone would make the swap worth while.

 

^^This

RB makes a carb conversion manifold, my concern comes to spark. Can you swap a 12A front cover on, or would you need to make a crank trigger setup? Really a crank trigger probably wouldn't be too bad, they make setups for muscle cars that could probably be eaily modified to work.

This thought has crossed my mind about a thousand times as I've been deciding what direction to go with the Sauce. On one hand, a boosted 13b can be made to run like a raped date, on the other hand, if my thinking on this is correct, a Renesis swap wouldn't be too bad at all, if you're not concerned with gas mileage or emissions (which, I am not). Even still it would be pricey just getting the motor.

 

well having been around a Renesis FB for a while my friend put together here are some thoughts / realities.

1. You need the 2004 ECU and wiring. This, once flashed by Racing Beat, removes the immobilizier. No other year can be removed. Harness wise, really only need the required sensors, ECU, and the engine bay wiring harness, fuse box (but that might have been able to be worked around, but it was easy to use).

2. He used the 6 speed and had a driveshaft made / modified

3. You will have to make the engine mounts. Best choice, do the FC subframe swap too. Easier fitment when you do not have the terrible FB steering assembly in the way.

4. Most of the power and driveability of this engine is the design of the manifold and the ecu. The manifold has variables the ecu controls. You will not replicate this with an aftermarket ecu unless you spend all of the money tuning, or yourself are the Mr. Miyagi of MoTec. The stock ecu can be made to work and it works DAMN well. Also a cheaper choice.

5. Pardon my distain for carbs, but carbs are for pasta. Might as well do with something older if your going to do that.

6. On the stock gearing, the car is an absolute RIOT to drive. You will want LSD, and you will immediate hate the stock brakes.

 

how does it not have a bunch of different codes for oddball stuff?

 

the 6 port engines are 232hp stock, and its actually easier to work on than a 12A, IMO. you clean a couple things, check a couple things and it works

 

Well living in Texas with a car over the age of 25 emissions isn't a problem, all we have to do is safety.
I like NA, turbo is cool but I'm a simple man and like the minimalist look.
This idea came into my head when I thought about making a first gen a daily driver. I travel a lot so gas mileage is important. I thought a renesis would be the answer to my problems.
Now I know why 12a's are taken for this swap. You'll be swapping the whole car out, it would no longer be a gsl-se.

 

if your doing the FC subframe swap the GSLSE rear is nice as you can run the 4x114.3 hubs and have matching front and rear lug pattern witout having to order moser axles and what not.

 

I think it might through a code, but that code doesnt affect the running of the car. No limp mode thrown. Now if your in some **** state that wants to check your 1982 Rx7 with a CAN BUS connector... well that might be an issue? But might be worked around. Racing Beat may be able to tell some codes to "STFU"

 

This thread is a perfect example of why the first gen section of this site is so cool. The OP asked, what most would consider, a very general question and no one got bent out of shape and immediately screamed at him for not searching etc. He probably would have been flamed out of the place in any other section lol. Thanks for making my job easy guys

Back on track - Gravity Fed, you said he just needed the engine harness and fusebox, wouldn't you also need at least a portion of the dash harness since it looks like he's also using the rx8 gauge cluster? Correct me if I'm wrong, I only had time to glance at one vid and it looks like the rx8 gauges...

What did he do for the speedometer since the rx8 uses ABS sensors for the stock gauge? I didn't realize Racing Beat had the ability to reflash the ECU - that definitely makes the swap a bit easier.

Rx8 engines seem to be getting pretty cheap on the used market, I might have to look into this more....

Redliner223 - just some food for thought. The T2 engines are, in essence, very simple things. In my opinion they are simpler than the 6 port NA rotaries and can be had quite cheaply. If you don't have emissions you can further simplify them. I have to run all the emissions on mine, it still makes great power and even with A/C on this time of year I'm getting 21-22 mpg on my commute which is a mix of highway and stop/go... Just something to consider

 

RX-8 is the new FC, IMHO

 

well we determined that you don't need the gauge cluster, its just handy for a selected few gauges that work. The speedometer and fuel gauge didnt. But you do need the throttle pedal and wiring to that.

he uses the GPS on his phone. We had not derived a solution for a functional speedometer. or fuel gauge. An autometer digital could work with teh custom calibration, or the stock cluster perhaps but the tach is an inaccurate pile of crap. mine reads 1000 rpms higher than it really is after about 5500. So i would recommend an aftermarket tach and fuel level.

i currently looking at picking up a engine, trans, and all wiring / ecu for 2k.


other considerations:

power steering... well not sure how you would do that since the Rx-8 is electric. There is a company somewhere making electric racks now though. This car in question is a manual FC rack w/ FC subframe.

I know we didnt need the A/C, Cruise, Radio stuff, etc etc. Things that seemed logical to the operation of the engine were required. Technically you do not need the electric air pump thing either. The RB header can even delete it. Which i would do because its silly.

this car used the Rx8 radiator mounted accordingly. We did find that we had to duct the air intake much like the Rx8 to draw fresh air. Car did not like air from the engine bay.

This is a returnless system requiring 60 psi. I believe we used either the C5 or C6 fuel filter. Which is for a returnless system, but is actually also a self regulating fuel pressure thingy for 60psi! has a return that comes off of it. So viola! fuel system.

The stock fuel tank can go in a few ways. Modify to accept something like an FC drop in, or use an external walbro. My FB rally car is EFI and i used the run of the mill tank. I didnt make new pick ups, or returns. Works just fine so far.

 

I'm quite happy how this thread turned out. I was just hoping for one or two posts on what would have to be swapped out and not this very insightful information which I'm very happy and grateful for.



These guys used the rx8 gauge cluster.
This is the article that sparked my interest in the topic.

 

Man that pic brings me back a few (many) years.... That was probably the first Renesis swapped SA (they're all SA's in Japan) any of us saw. IIRC that article is from 2004.

Thanks for the info Gravity Fed. If I were to do this swap it would be on my already FC subframe swapped car, so no need for power steering... A/C is something I'd like though. Guess the best thing to do would be to get the Rx8 FSM and start looking at the wiring diagrams. Can't be THAT hard can it lol

 

exactly! we figured it out.

Hopefully ill get my hands on teh engine stuff here soon.

 

Hmm, you've got my wheels turning. I love my T2 swap, but a renesis would be pretty damn cool....

 

the Rx8 engine has much fewer emissions parts than a 12A, its just a cat, and electric airpump

 

i really like my Rx8

 

does that mean they're the new parts supply for 1st gen's ?

 

Is there any benefit to the Renesis block itself? I've never worked on one, from what I've read its intake ports are big and it has 10:1 compression, but the side exhaust ports are not as free flowing.

Say I were to get Racing Beat's manifold adapter and put downdraft ITBs on with RB's header as well. Would this be any better or worse than doing the same with a previous generation 6 port 13B?

Another idea, what if one were to adapt the Renesis intake to an older 6 port to combine the sophisticated intake with free flowing headers.

 

Cheaper to buy an rx8