Rx8 engine + rx7 turbo kits into a mazda 323f
 

Hello everyone. I am going to start by saying that if there is another topic about the rx8 engine and why it can or can`t work with a rx7 turbo kit, as far as i know rx7 has two turbos.
Ok now for the real stuff. I have recently aquired a mazda 323f zxi 2l v6 24v and as crazy as i am i want to power it up higher as i love the engine sound and i believe the rx8 and rx7 have very good kit inside, which would bring the 323f on par to newer cars and bring it back to life. My knowledge about the difference between the rx8 and rx7 engines is slim, except for knowing that the rx8 engine is supposed to be better on the rotor side and need less oil. On the performance side i know the rx8 has no turbo and is inferior to the rx7, but i don`t know if its because of the lack of turbo or just the way the power/weight works out or ecu mapping. Again, the car i have has no turbo and only can manage 150hp and only 9.4sec 0-60. It still is a nippy car but i want to consider upgrades.
I know the k engine inside is increased to up to 2.5l in the ford probe but it doesn`t seem to compare to the prowes of the rx7/rx8 rotary with each at 5.3/6.3 0-60. I know what i`m looking at is extreemly over the top and most likely my 323f will need a full work out and a complete strip to ensure the chasis is capable of withstanding the forces involved. I am opening an open discussion about the posibility of actually doing the changes not the insanity behind it.
On a side note, i want to steal the pop up lights from an rx7 and retrofit them to the 323f :)

Looking forward to your replies and your ideas, btw i simply love the 323f zxi and the noises it makes, but i`m sure the rotary is much better :p:

The renesis and the 13b are different in every way imaginable. its like saying a sr20det is just like a 4g63 becuase they have 4 pistons and dohc...

So if your really serious about the swap I suggest you read up on how a rotary functions and the mechanical differences between both engines. You cant slap on 13brew turbos to a renesis just becuase it has a rotary engine.

If I were you Id look into getting a sr20det and swapping it in. It would be just as hard as a rotary but you would most likely be happier. Ultimately youd be happier selling your car.

You are looking at a conservative $10,000 to do the engine swap alone, another $10,000 if you go forced induction, more if you encounter other issues. My plans for a Renesis swap into an NB Miata is on hold for the time being, one of the reasons is the rumor that is solidifying that the next RX-7 will be in an MX-5 chassis...solving my challenges ...plus a warranty :) The cost I was budgeting for was $12,000, and it was staying NA, and it was in a chassis that can actually accept it without massive work (like trying to make a FWD vehicle RWD, several sensor carryovers, etc...)

You have 2 separate projects here though. One being the engine swap.
The 323 is a front wheel drive vehicle. If you want to stay FWD, then you will have to figure out a solution to have the Renesis mounted sideways, and get it's power to the transmission. If you switch to RWD, then you have to get the drive shaft tunnel in place, and find an appropriately matching driveshaft and rear end, or have it all made. Assuming that you are willing and able to tackle all those challenges, don't forget the exhaust routing, the ECU you will have to buy and fully wire up.
$10,000 is a VERY conservative minimum cost.

Then there is the turbo project.
First, learn about the differences between the RX-7 and RX-8 engines. One is not "inferior" or "superior" to the other, they are simply different. The RX-7 can be turbo'ed easier due to lower compression rotors, and the port locations can be heavily modified for significantly higher air flow. The RX-8 engine has much higher compression rotors, so the margin of error is lower, and the ports can't be modified much at all. NA to NA, the Renesis in the 8 is more efficient and more powerful than the prior rotaries, but the prior ones generally have some level of forced induction on it. Take a stock 8, and turboing it is about a $10,000 project, assuming you don't do any of it yourself. The part costs are lower, the troubleshooting, tuning, and labor fees are most of it. Superchargers for the 8 are about the same, though most of the cost is in the parts, less in the labor. Tuning is equivalent. And then there is the extra cost for unrelated stuff that helps keep the power on the ground. Wider wheels and tires, suspension upgrades, gauges, etc...

You also need to learn about how turbo's work, and how ECU's work. And I don't mean "the exhaust pushes a paddle wheel which spins a turbine which compresses air". I mean air flow dynamics, air flow measurements, efficiency ranges, proper turbo sizing, top mount trouble vs bottom mount trouble.



Realistically, you are in over your head. Here is a life preserver. Start swimming a bit and you might reach land.

Yea what he said...

Hello everyone. Thanks for all your replies. In the end you both have a fair point and i think i went for running before i can walk. The idea of rx8 engine into the 323f sounds the best, the problem i`m facing now is deciding if i want it rwd or keep it fwd. I`m thinking of fwd since not a lot of high performance cars use it and there is no chance i can make the mazda into a 50:50 weight ratio.
Think the rwd conversion would be slightly easyer as the 323 has a middle tunnel, will have to invetigate what it houses, but so far i`m thinking its the exhaust, it is quite flat underneath, unlike most cars, so i`m asuming the exhaust has to be the culprit for the median tunnel. I`m sure the boot will be easy to convert to house the gearbox as the spare wheel is middle mounted, again will have to investigate the mounting point and see if the space saver spare wheel and the fuel tank are suitable.
For the fwd i might have to discuss depending on how i can squeeze the engine and gearbox in. My previous car had an inline 4cyl with gearbox behind, with driveshats coming from gearbox, again it depends on the angle and position of the engine. If not i will have to talk to ricardo and see if i can source out a suitable gearbox to mount the engine sideways.
Either way thanks for all the help to both of you and will inform on any progresses as time goes along :bowdown:

http://www.rx7club.com/showthread.php?t=92530

Read that and reconsider.

I can see no feasible way that a fwd transmission will hook up to a rotary.

This is a FWD engine notice to the right is a bell housing look at its shape and form.

http://carphotos.cardomain.com/ride_...0237_large.jpg

This is a rotary engine do you see the flywheel and size of the engine. The bell housing is huge when compared. It just wasn't designed to go FWD.


http://sphotos.ak.fbcdn.net/hphotos-..._3899666_n.jpg

You need to give up your rotary dreams... Go for a piston engine that is either fwd already for can be converted.

My intention was never to modify the engine for the fwd but instead modify the gearbox, the reason i mentioned ricardo is because they specialise in transmission and engines and could modify the rx8 gearbox if not make a custom gearbox that would put the rotary engine on par for fwd. In the worst case scenario i will just use the rotary engine in rwd mode and modify/adapt the underside

You clearly didn't get my point...

Look at the size of the bellhousing on the first picture its on the far side of the enigne on the right.

Now look at where the bell housing would need to mount up on the renensis...

Do you see the huge size difference?


Let me break this down for you I was trying to avoid this...

You would need to make it rwd.. that would require a rear subframe from a rwd vehicle that could be modified to your vehicle. you would need to cut out the rear section of your car and have the new rear subframe form your donor car welded into place the gas tank would would come out to and you would need to get a fuel cell which cant be used on roadways only on race tracks.

After you get all that figured out and a whole new rear made for your car you will need to get a custom driveshaft made and a custom bellhousing or a fabricated one.

you then need to figure out how to mount the engine which would require custom motor mounts and a fabricated engine bay. now you need to find room for all your cars electronics headlights etc all need to get ran somewhere.

the engine would need to run off a stand alone ecu Haltech or similar. all the sensors and harness needs to get refitted to take a haltech system. after all that work is done you need to figure out how your going to mount all the body panels back up since you essentially chopped your car in half and put on a rear end form another car.

and after all that work you wind up with an engine that will produce 220 whp max N/A and will need to be rebuilt every 60k. And lets say you get a 13B REW or a turbo II engine. you still wind up with shit horsepower and an unreliable engine.

You would be better off buying a bmw 335I and chipping it giving you 370 whp.

Do you understand why it wont work yet?

You do know that there is a FWD rotary civic? and it runs?

http://www.youtube.com/watch?v=zsCvrGt52uw&NR=1

That has to be a screamer.

I stand corrected. Go for it kid knock your socks off.