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-   -   renesis swap in an fd (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/renesis-swap-fd-729487/)

RENESISFD 02-11-08 02:14 PM

renesis swap in an fd
 
First off i would like to start off with that i know that this question has been debated on this website however they all seemed to turn into an arguement and they didnt answer the questions that i have. From what i have read there is no one who has done a renesis swap (i could be wrong). I understand that the renesis has less power than a 13b-rew however the renesis is n/a. In my opnion it seems that a PROPERLY turboed renesis will make more power than a LIGHTLY modified 13b-rew. Also a n/a renesis would be a much better in terms of reliability imo . I am fully aware that the six speed is weak. My main question is can it be done ( i know that with enough money and time it can be done) but does anybody know approxmately how much time and money, are there any clearance issues or smething major that i am missing. My reason for asking is i am planing to buy a roller fd soon and trying to consider my options. I am not looking to make big horsepower i dont want to hear about a 3 rotor swap. i personally dont care about them. (dont flame) If nobody has done this then i will definately try to do this and post pics, if it can be done or not. Remember i do not want to start an arguement. I had seen a picture of an fd which claimed to have a 6 speed in it and the shifter was a couple of inches from the stock location. Would this be a problem if the car had a renesis motor in it?

GoodfellaFD3S 02-11-08 02:22 PM

I think it's a silly idea. Drop in a 13B-REW and be done with it. side exhaust ports are a step backwards (when it comes to a boosted motor) in my opinion.

Mahjik 02-11-08 02:23 PM


Originally Posted by RENESISFD (Post 7853793)
In my opnion it seems that a PROPERLY turboed renesis will make more power than a LIGHTLY modified 13b-rew.

Well, I don't know about that. Here are some stats on FI RX8's:

http://www.rx8club.com/showpost.php?...26&postcount=1

You can easily & "reliably" obtain those numbers use the stock twin turbos and the 13B-REW. Your "reliability" is only as good as your tuning, and that's going to be the common link between the two.

IMO, unless you just want to be unique, it's going to be more effort than it's going to be worth performance or reliability wise. Keep in mind, the 13B-REW was designed to be FI from the start, the Renesis was not.

arghx 02-11-08 04:08 PM

The Renesis is a great motor for what it is. Compare it to the 89-91 nonturbo rotaries and you will see that it has something like 80% less emissions, similar gas mileage, yet 50 more horsepower to the wheels or so (mid 120's vs mid 170's. yes many/most dyno in the 170's, not the 180's, depending on dyno conditions etc) and more torque. unless you have insane fabrication and tuning skills (and money to blow) don't try this.

s-thetikz 02-11-08 04:25 PM

the renesis is not meant to be fi . not how it was designed. everyones thought about to be original, but no.

dgeesaman 02-11-08 04:38 PM

Basically if you're going to drop in an engine that isn't a 13B-REW you're creating more work.

For the amount of hassle involved, I personally think going V8 or 20B make the most sense, 20B being the less practical of the two. But the rewards are great.

Putting in a renesis is harder than a 13B-REW, but for less reward. Granted, it doesn't compare to a 20B swap, but it's far from a drop-in. By putting that time/money into a 13B-REW you can do some pretty intense stuff. I don't think it's worth it, but that's your decision.

FD3Smaniac 02-11-08 04:41 PM

honestly i think, if you have the time and money for a project like this, and you think you/shops tuning would be good on this, then go for it, i have not seen this done before and if it didnt work out like you hoped, sell the renesis off and swap in your REW, as long as you got extra time and money go for it. I would love to see the end results in this kind of project. and as for the transmission sitting different, i think its going to end up in that same position as the picture you seen ( i seen the same picture your talking about), unless that area of the engine is a little longer. or if there is room in the back, you could fabricate your own mounts to sit back an inch or so to help it out.

Miata_mx5 02-11-08 05:07 PM

I saw 2 FD3Ss in japan that were in the 350 hp range (stock twins) running the renesis 6 speed transmissions. Both were cars that R magic did for clients. I saw one roller being prepped as a track car that was going to run a ported renesis engine with individual throttle bodies.

It has been done before, and it can be done if you have the cash, and resources. Custom work is a given (needed).

2FAST7S 02-11-08 09:00 PM

If you want the Renesis, why dont you just get an RX-8? Seems to be more like what youre interested in...FD with less power, more expensive, WHY? 6 gears that important?

OneRotor 02-11-08 09:11 PM

it can be done, like it was said above, but you're going to need some good fab skills. Yes, it will be unique, but why would you want to spend all that money to reduce your performance? I know you don't want to go with a 20b, but if you don't turbo it you aren't looking at nearly the expense. A solid, street port 20b will give what, 350 whp n/a, and 300+ lb-ft of torque. yes, it's a bit heavier and you'll get worse gas mileage, but it'll be more reliable than the renesis.

The Renesis CAN be done, but WHY is the real question.

RotaryResurrection 02-11-08 09:11 PM

FYI the renny 6sp trans is a lot weaker than the FD/FC turbo gearboxes. They barely hold up to the torque of a stock rx8.

I would probably not consider a renny in an FD because the mounts, plumbing, and electronics are totally different. The best thing you can do is just go with a stock rebuilt rew, completely go through the fuel and cooling system, use new gaskets on the install, and either run a small sized single roughly equivalent to the airflow of the stock twins, or run a set of rebuilt twins. You can be pretty reliable for years this way, and if you learn how to drive the car just right, you can stay out of boost and get good mpg (20-24) as well.

Oh, and as an rx8 owner, the thing (within reason, budget considered) that I'd most like to do with the car is do a no-emissions REW swap with sequential twins, intake and exhaust and let it be. It would be a lot more fun that way.

Herblenny 02-11-08 09:20 PM

Another thread about Renesis in an FD.. GOD WHY?? I wonder where in the hell these kids get this info??? Stop listening to some 8 owner who doesn't know a thing about rotaries..

If you want this damn engine, then get an RX8! RX8s are getting so cheap, its almost the same cost as decent condition FD. 8 handles well, more comfortable, gets worse gas than FDs, and suspensions are newer.. So get an 8 if you want the engine:)

gracer7-rx7 02-11-08 09:44 PM

At least its a little more interesting than the 2 page BOV thread we had last week....

FD3Smaniac 02-11-08 10:33 PM


Originally Posted by gracer7-rx7 (Post 7855787)
At least its a little more interesting than the 2 page BOV thread we had last week....

haha 100% true... i did some research on this after i made the last post... and i found some with the renesis in it... those guys have MAJOR cash into those cars, and tons of fab hours.... dont do it, for the sake of your time and money, its a waste. with the money put into this project along with time, you could make an AMAZING 13b-rew

RENESISFD 02-12-08 04:33 PM

I understand what you guys are saying, but it seems to me that it is a lot of work, but i dont understand why. it seems that one would have to make motormounts, transmission mounts and a couple of other miscelanious stuff to make it work. what else am i missing? I can do the fab work myself, that is not a problem. And if i use the motor in it's stock form, then there would be no tuning that would have to be done; untill it is turboed or supercharged. Does any body know what a stock fd has horsepower wise to the rear wheels? The reason why i was thinking of doing this swap is because it is fairly unique. also i dont like the look of the rx8. does anybody happen to know the distance from the back of the 13b-rew to the shifter, and the distance from the back of the renesis motor to the shifter?

RotaryResurrection 02-12-08 04:37 PM

The renesis trans/shifter sits farther forward in the cockpit. You'd want to keep the clutch-back drivetrain FD, and just put the renny in front of it.

The renesis is VERY electronics dependent so you will likely need to find a whole partscar to pull wiring from. The PCM/ECU is not very easy to work with, unlike the earlier rx-7 computers. I am telling you this will not be remotely easy. I think the only feasible way to do it would be a standalone.

dgeesaman 02-12-08 04:38 PM

Give it a try and let us know how bad it is.

Mahjik 02-12-08 04:45 PM


Originally Posted by RENESISFD (Post 7858839)
Does any body know what a stock fd has horsepower wise to the rear wheels?

A healthy stock FD will be about 215-220rwhp.

gracer7-rx7 02-12-08 05:17 PM

And a stock or modded RX8 puts down about 170-190 rwhp.

- custom motor mount setup
- PPF modification or some other means of keeping the tranny and diff properly mounted and such
- custom driveshaft
- RX8 fuel system is returnless so that needs to be modded
- RX8 uses an ethrottle so you'd need a standalone or lots of wiring
- rear gears should be updated also as the RX8 uses 4.44 gearing compared to an FD 4.10

Lots of work and parts for not much benefit.

Archie 02-12-08 05:27 PM

Just buy an 8. I have both and they serve their purpose. Renesis is a step backwards for an FD IMO, but if you have the time/money/resources... don't let anybody discourage you. Do what you want, isn't that what this hobby is all about?

FDTT19 02-12-08 06:26 PM

^ don't be so encouraging, because then he may actually execute this dump idea.

TRISPEEDFD3S 02-12-08 07:32 PM


Originally Posted by gracer7-rx7 (Post 7858993)
And a stock or modded RX8 puts down about 170-190 rwhp.

- custom motor mount setup
- PPF modification or some other means of keeping the tranny and diff properly mounted and such
- custom driveshaft
- RX8 fuel system is returnless so that needs to be modded
- RX8 uses an ethrottle so you'd need a standalone or lots of wiring
- rear gears should be updated also as the RX8 uses 4.44 gearing compared to an FD 4.10

Lots of work and parts for not much benefit.

You mean NO benefit right?

RX7LINK 02-12-08 07:36 PM

Its your car, do what you want man. Its understandable if you like the looks of a 7 but want the reliability of a 8. (thats if you keep it N/A like what it's designed for). I'm sure the engine will last a lot longer and probably won't throw off the weight distribution as much as droping in a V8, I6, I4.

but then again, who has the patience to stay NA when you've been spoiled by the turbos boost. If you want to drop in a turbo for the renesis, you're better off staying with 13B-Rew

RotaryResurrection 02-12-08 08:44 PM

In reality, the renesis has not really proven itself dramatically more reliable than a well built, reliability-modded turbo rotary. I have one of the highest mileage renesis' in the country that is still original, but there are a lot of 30-50k mile renesis that are getting replaced as we speak. A properly setup 13brew with light mods can make 100+hp/tq and still last that long or longer.

FDWarrior 02-12-08 09:14 PM

I dont get why you want to make an FD slower. The point is there are plenty of unique cars that suck. Like this car http://i184.photobucket.com/albums/x...iRX7/civic.jpg Dont be someone who ruins a car just to be different.

Herblenny 02-12-08 09:46 PM

LMAO!!! Ramy, that thing is AWESOME!!

OneRotor 02-12-08 11:41 PM


Originally Posted by RX7LINK (Post 7859635)
Its your car, do what you want man. Its understandable if you like the looks of a 7 but want the reliability of a 8. (thats if you keep it N/A like what it's designed for). I'm sure the engine will last a lot longer and probably won't throw off the weight distribution as much as droping in a V8, I6, I4.

but then again, who has the patience to stay NA when you've been spoiled by the turbos boost. If you want to drop in a turbo for the renesis, you're better off staying with 13B-Rew

don't spread mis-information. a LS* swap is barely more heavy, if not lighter than a 13b-rew, plus you get the ridiculous overdrive for highway cruising. this is not an argument thread, it's an opinion thread, but state your facts correctly.

Natey 06-04-08 11:58 AM

http://www.msprotege.com/members/Natey/rx7/renesis1.JPG
:wave:

n rider89 06-04-08 01:05 PM

lol.

also i have a question, would swaping in a ren be an actual legal engine swap? (assuming you keep all the emissions stuff)

RLaoFD 06-04-08 05:50 PM


Originally Posted by Natey (Post 8255593)

LOL thats good enough for me

Hitokiri_Gensai 06-04-08 06:16 PM

nice pic xD epic. xD

ok, you know putting an engine into an engine bay not meant for it, is not as easy as just "making mounts" and putting it in. it has to be PERFECTLY lined up... otherwise youll wear the driveshaft apart and start ruining bearings. There is a TON of work to do. its not nearly as simple as just doing that. Count on that short block being in and out maybe 10 - 15 times JUST TO FIND THE FITMENT.

there is NOTHING easy, simple, or cheap about the project your undertaking.

Also im not sure if you've driven an 8 but they are HORRIBLY torque deprived... on the highway to get some get up and go, were talking about being in 3rd gear before you get the damn thing to move.

By the time you tear down that Renesis to set it up for a turbo, your talking tons of money. Remember, you cant extract high boost numbers out of a Renesis because of its high compression ratio. It was made to be N/A, turboing it with any real power requires that you pull out the rotors and fit lower compression rotors to handle the boost.

By the time you get this project done? your going to be sitting on top of a mountain of money that could have easily been spent in the pursuit of making a 13B-REW run reliable and powerful.

a stock JDM 13B-REW can be had from a reliable engine source for like 2000, you can get a BUILT 13B-REW short block from a reliable source for like 3500, so why would you spend TENS OF THOUSANDS building up what will essentially be a single turbo REW out of a Renesis?

Prometheus 06-05-08 02:25 PM

My Opinion
 
In my opinion the only way I would ever switch to a RENESIS Engine in my FD is if there were 1 or 2 extra rotors:lol:

I have seen a RENESIS pulled apart, and honestly when I really took a good look, it seemed like an Engine that should never be boosted.

I noticed right away that it looked like the apex seals were much more shallow than the REW seals. (I think this is to prevent the seals from getting exposure to hot exhaust gasses (because of the side porting)

shallow/ smaller apex seals and port placement of the RENESIS throw up red flags for me. I honestly don't think it could hold up to detonation, but its not like the REW holds up to detonation all that well either...

Horesepower is a double sided sword.

From what I've seen with my own eyes on a track (not a drag strip) a 400 H.P. car goes just as fast as a 1000 H.P. car.

form multiple post that I have read 400 R.W.H.P. is about the peak power you want for tracking your car, other wise you are fighting your car, more than you are enjoying it.

Natey 06-05-08 04:03 PM

Just wanted to make a note that whaile I was at Laguna Seca for the Monterey Festival Of Speed a few weekends ago, I got a good look at the Speed Source RX-8, which is 3rd in points in the GT Rolex series.

It's got a n/a 3-rotor with 13B housings.
http://www.speedsourceinc.com/client...ews/3372_l.jpg

n rider89 06-06-08 05:46 AM

3 rotor renesis:

http://ausrotary.com/download/file.php?id=803

http://www.youtube.com/watch?v=uTMBZrnFe6c
http://www.youtube.com/watch?v=IoXhZ0i1zdA

real1st 06-06-08 07:02 AM

--
 
That is hilarious. I admit I drove a civic once, but it was simplistic and clean. Modified to hell, but that civic is hilarious..

Makes me happy that I no longer drive one.. I will stick with my rx7 and bmw..

Thats priceless..

real1st


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