I'm thinking about getting an 86 sport (only 2600lbs) and dropping in a Renesis instead of doing a V8 conversion I previously planned on doing. I've got about 9K budgeted for everything, including the purchase of a car.

Is 9K enough for the swap? I really want to stick with a rotary but the cost to pleasure ratio is better with the LS1 swap.

 

No one has tried it yet (to my knowledge), but I can almost guarantee that it'll cost you more than a V8 swap. It's complicated.

 

If I were going to swap out the motor, i would atleast put something better in there than a Renesis...

 

The renesis weighs 100lbs less than a 13B, so that will bring down the total weight to 2500lbs. Uncork the engine with an ECU swap and other junk and it'll be pretty quick. Close to 300hp in a 2500lb car...

I'm not a mechanic, but I would think it would be easier to swap in a Renesis engine of the same capacity as the previous motor than a big 5.7 liter V8.

 

If you save up a little more you could do a N/A 20B

 

Um Im pretty sure that the Renesis doesnt weigh very much less than the 13B. You might be thinking of the 13B-REW with its twin turbos and such, but a 1.3L n/a rotary is going to weigh close to the same weight as a 1.3L n/a rotary.

 

How much would that swap cost? I'm not familiar with the Cosmo engines.

 

Let's see, a $400 RX-7 with blown engine
+$~1500 13BT conversion cost
+$7100 worth of mods

that will be faster then any LS1 swap.

 

this same exact question was actually just asked a couple weeks ago. The renesis would be a waste of money. Either put in a S4 turbo conversion with a ton of mods or use your cash as a start to the 20b swap. The renesis motor will be a pain in the ***, and really not worth it. There are guys on this forum with 400hp S4 and S5's and I bet they cost a lot less than the renesis.

 

Well. heres my opinion.
Say you were building an awesome N/A car. no one is totally certain how much power can come from a fully ported/moded renesis. it just hasnt been done. Many men of unlocked full potention from your typical every day N/A motors. and have had good luck doing so. But think.. about cost, about availibility ect. I suspect a Renesis motor (brand new) is somewhere in the area of 7-8K. just because it's an amazing motor and BRAND NEW!!

But... and i'll cut this short. 13b N/As are everywhere, find one and mod it, go 3 rotor ---OR--- do something i'd never do :Leave N/A's and go for turbo.

-Markus

 

GHEY!!!, the renesis on the rx-8 only makes 180 at the wheels!! port a 13b and you will get 150 at the wheels ( and tahts with a street port). get true duals thats 165 at the wheels. so some other mods and you will save like a mother shopping in walmart with discount paper cutouts!!!

 

9K is good down payment for RX-8

 

Dude just drop in an LS1. So much cheaper, and so much more torque. To hell with all those idjits that claim it's sacrilidge. Who cares, its your car, do what you want with it. The renesis would be a waste of money at this point. It hasn't been fully dissected by the performance community to know what it's true potential (and potential problems) are/will be.

A properly done V8 conversion will only weigh a couple hundred pounds more (about the same as doing a 13BREW swap into an NA), and depending on how far back you place the engine, you can still have your 50/50 weight distribution. Plus think of the POWER!!!! Search this site, there are a few videos of LS1 rx7's ... holy **** on a stick, do they ever go!

 

i get the renesis motors for $6093.20 if you need one

 

Im not sure where you would aquire a renesis for 6000 dollars. I cant get it for that and i work for mazda, wrecked cars already??? I went to RX-8 training a coulpe months ago, the instructor said that each renesis is hand built in japan by a team of technicians. This is why the motor costs 12-15,000$ to purchase. As for the renesis being 180 rwhp, thats not true. You've been reading about some idiots in the states who were dynoeing a fresh renesis not knowing that there is a breakin period bult in to the pcm, which restricts the output of the motor quite a bit. Mazda has dynoed the renesis at 238 hp, 12 hp shy of previous claims. For this reson mazda implemented a buy back plan or free scheduled maintenece to compensate the new owners for the overstated hp figures. Ive driven like 6 rx-8s, they (even restricted), are very quick, solid cars. If you see the exhaust restriction on these things, you would know these motors are capable of 300 rwhp, with porting and exhaust ect. As for a renesis swap, youd never get one done, you have to pay 10 plus for the motor, then wiring harness, pcm ect ect ect. Get a j-spec cosmo 13b, ported , turbo, standalone, and say goodbye to LS1 or renesis. Guy who says Ls1 conversians isnt sacrelige, i agree, but there no point to doing one when rx7 have the most unique, exremely powerful and well aftermaketed powerplant there is available. Put a v8 in a hotorod for the wifey and build a car that is really fast.

 

if you want to go goofy, oringinal and stay n/a, then go to guru motorsports, they have two peice eccentric shafts, where a bearing is pressed in the middle plate. Last i heard they had an intake as well. You could easily have a n/a capable of waxing turbo cars (lightly modified)

 

IMO, i'd go with a 3 rotor too!

stay in the mazda family man!

 

It was very easy i found it in 5 min,called my guy up at motorsports and found it, i can get the part number for ya.

 

stroker they are brand new not out of a junked rx8.

 

im pretty sure thats 238 hp at the flywheel, not the wheels

 

There`s your answer. $9000 ought to about do it! Just doesn`t seem worthwhile to me though when an LS1 is in the same ballpark moneywise and puts out almost double the HP and more than double the torque.

Toughguy

 

yea it just is'nt worth the money for the swap.

 

But then again, sometimes it`s not always about the money spent and what you get out of it. Sometimes it`s just to be different, or at least the first. I`m sure in several years the Renesis engine will become more available to the motor swappers and many of them are sure to find their way under the hoods of all generations of RX7s.

Toughguy

 

You can narrow down your engine choices a lot by answering the following questions

1. Does the engine HAVE to be NA or can it be turbo?
2. How much RWHP are you aiming for?
3. How rare do you want it to be? Same performance for 1/2 the cost by doing a 13BT with say a T04E.

(and of course always the cost factor of everything)

 

1. The motor does not cost 12-15000. If it did, the RX-8 would cost more.

2. All rotary motors have been hand assembled new. It's always been like that. So why would the renesis cost three times as much new? It's nothing over the top.

3. With enough money and time, anyone could get that swap done.

4. Electronics. Four words: Aftermarket Engine Management System.

5. Aftermarket support. Right. Do me a favor and find me 4 divided cast iron exhaust manifolds for a 13BT...you won't.