Hi, does anybody know the actual dimensions of the RENESIS? For example, would you be able to swap it out and put it into a Miata or Honda Civic del Sol, which have fairly small engine compartments?

 

Well I don't know the dimensions of the renesis. but I have heard people putting in the 13B in a miata. And since the only real difference(I'm probably wrong, someone will undoubtedly correct me in this forum) between the 13B and the Renesis is the porting.

But if you think about it you can practically fit an engine of another car as long has there is ample space and frame support(strength).

 

People have put 13b's in miatas, but it requires alot of custom fabracation to do. So in theory you can put any engine in any car, it is just how much you want to pay.

 

I've always wondered under what would you register a car if it has a body of one car brand and the engine of another. If you build a car for yourself and put in whatever engine and pass all the safetey and smog tests. Under what category would you register the car in. And of course its for daily driving.

 

stripped to just the bare block and head (or the rotor housing for the 13B), The 13B is SLIGHTLY shorter and wider than the 1.6 Miata BP block.

on that note, I hold anyone that dare to put a rotary in a Honda in contempt

 

State DOT agencies will normally classify by VINs. So, if you have a Miata, and you install a 13B or a V8, it is still considered a Miata. In places like Colorado and Texas, even in smog areas that require strict emissions, all you have to do is pass a smog test and other safety checks (Texas is much more thorough in it's safety tests than Colorado). They are supposed to check to make sure that you have the basic smog items present, but that's it.

California, and anyplace which decides to adopt CARB standards, is a different story. ANY non-standard part that has to do with emissions has to be certified by CARB, which is very expensive and time consuming. In other words, homemade turbo setups are not legal in California, regardless of whether or not they pass smog. I don't know how they handle or classify engine swaps.

---jps

 

The Renesis IS a 13B. Displacement is the same, the eccentricity is the same, the generating radius is the same, and the trochoid width is the same. These are the things that make it a 13B in Mazda nomenclature.

The porting is different, there is a new induction system and other changes, but the name is 13B-RENESIS.

Putting any 13B in a Miata is just a problem of how much money you have, it can be done.

 

...the internal geometry of the engine is, for the most part, identical to the 13B, but the RENESIS isn't "the same"...

mounting points, and even brace height, and tranny mounting points are very different between the engines.

 

The internal dimensions for the RENESIS aren't "for the most part" identical to the 13B, they are identical to the 13B. The internal dimensions I am referring to are:

Chamber width (rotor housing width) - 80mm
Generating radius (distance between rotor centerline and rotor apex) - 105mm
Eccentricity (offset between eccentric shaft centerline and rotor centerline) - 15mm

These are the dimensions Mazda uses to calculate their rated displacement.

V = 3 x (square root of 3) x Reb

where V is single chamber capacity (one rotor)
R is generating radius
e is eccentricity
b is chamber width

Yes, exhaust ports have moved to side housings, mounting is different, and there is a different tranny behind it, but the RENESIS is a 13B. It's just a further evolution of the same engine that has been around for 30 years (13B first appeared in the RX-4).

 

Haha.. How about the Renesis in a CRX or dare I say S2000? :p

 

...i've heard tell that the e-lobe may have an 11mm stroke (over the 10mm stroke from 13B's), the rotors are different (shaved on the edge from the factory... at least in every cut-away motor pic i've yet seen)... these may not be your definition of "internal measurements", but it's a different engine. it's an evolutionary engine (i never said it wasn't), but the port placement, differences in the side (and especially intermediate) housings, placement of the outer gears, location of the side-seal groove.... this is a different block, has different rotors... it's a different engine, with most of the same measurements.