vipernicus42

iTrader: (4)

Wow that link is just FULL of awesome stuff...

Apparently the engine has the same external dimensions as the RENESIS 13b... the combustion chamber's trochoidal shape is larger, but the cooling passage is thinner, so the overall shape is the same. That means that the engine very well may bolt up to the stock RENESIS transmission...

Reading through it, the change in shape helps reduce energy loss through heat, increasing thermal efficiency. So a larger water pump may not be needed...

Now I'm really anxious to see this thing. The question still remains: when will it make an appearance?

Jon

dj55b

iTrader: (2)

i was just about to correct you ... why would it be too true to belive that they're doing dfi?

PercentSevenC

Mazda's rotaries have had staged injection from the beginning. It's reasonable to assume the direct-injection will be primaries only, and the others you see are secondaries. Who knows, maybe they'll even have some "tertiary" injectors in the intake manifold for when the auxiliary ports open.

Joker1337

But does the "reduce energy loss in heat" part apply to change of the combustion wave such that more of the power in the fuel is translated to a more efficient T/P/V contour or does it mean that because the irons are thinner they convect less heat into the engine compartment? You can get more "efficiency" out of either one, but one's gonna require more care from the cooling system than the other.

axle

as to the cooling craziness an all aluminum block will cool easier then the aluminum and cast iron that is currently being used so that is an added plus you just don't want to over heat it or its an entire engine rebuild

Jeff20B

iTrader: (13)

The Renesis 13B was cool but I didn't really feel a great need to make an attempt to install one in an earlier chassis. Too many differences in front cover guts and oil pan length, needing to mod the motor mounts blah blah blah. Now with this new 16X thing, I am finding reasons to want to install one in my REPU. The torque! No need to destroy the engine bay fitting a 20B or V...something. Well you know.

Since this new engine is the same length as a 13B Renesis, I can make the necessary mods tot he engine bay feeling confident that they won't detract from the heart of what Mazda was trying to do with these trucks. Heck the 15A was supposed to come out and go into the REPU and Cosmo (RX-4 as well I assume). So I say why not? Instead of a wider rotor they went back to 70mm but made it taller. I can live with that (the 15A was to be 90mm wide). In the end the engine will probably end up as long as the 15A in the engine bay, or any 13B Renesis for that matter, but if it's just a matter of 20mm or so extra, I can swing that. What I won't do is try to squeeze an engine 160mm longer than the stock 13B. A 3 rotor 12A would have been nice but again the length is an issue at 100mm longer.

Does anyone know how much longer than a 13B these Renesises are?

dj55b

iTrader: (2)

We'll just have to wait and see how the whole injection system is done up first on what ever car it comes on. The Renesis from what i hear is not all that friendly to swap out.

sen2two

iTrader: (10)

its not that hard to put a reni in a 1st gen. very identical to any other 13b swap. 12a front cover, timing gear, and modify oil pan...

now intake/exhaust/fuel...thats where the fab comes into play for real. but getting in there is easy.

Yellow S2 Rx7 13BT

mmmm new 7 round the corner I reckon!!!!!!!!!
now i have 10 posts woo hoo

vipernicus42

iTrader: (4)

For the swaps, it's still a matter of us thinking too small. I'm sure on Ausrotary somewhere they're already talking about how to make a 3-rotor version of the 16X (which I guess would be a 24X?). Go big or go home eh!

Jon

PercentSevenC

I have to correct myself. They've had staged injection only from '86 on. Forgot that the HB Cosmo and GSL-SE motors only had two injectors.

ray green

iTrader: (14)

And I do believe my 84 GSL has a carburetor, no injectors at all unless you want to count the OMP.

PercentSevenC

Well, yeah. I meant the ones that have fuel injection.

DC13B

all i can think is PP 24x race engine

axle

with direct injection you don't have an intake manifold you have a couple of injectors that empty straight into the the rotor chambers no more dealing with turbulence in the intake. the air fuel mixing would be done in the fuel line just before the injector notice the electrical plugs on top of the motor right there with the injectors

PercentSevenC

You know what this post reminds me of? YouTube comments. I've been seeing more and more of these lately on this forum.

DC13B

^hahaha so true

BlackWorksInc

YouTube posts? Who does that mean exactly?

DC13B

means that its full of fail and stupidity.

very few people actually know what they are talking about on youtube.
lol, i could disect his post is ya wants

PercentSevenC

Obligatory:

http://xkcd.com/202/

Jeff20B

iTrader: (13)

Giant hammer, little nail, hit squarely right on the head.

zeroecco

lol,

I have a question about the heat issue. due to the different expansion rates of iron and aluminum if you over heat the f***** your screwed, you'll warp the motor and have massive internal damage. However, with an all aluminum system is there a potential for same rate expansion and thus a little bit more room to save the motor? what about the DFI, is it true that the intake velocity is not longer important? Could you just cut massive ports into the motor and add power?

-richard

PercentSevenC

I suppose in theory severe overheating is less likely to damage the rotor housings (I could be entirely wrong; someone else care to comment on that?), but you're still destroying water seals, which means a rebuild anyway.

Intake velocity is still very important. The goal is to ram as much air into the engine as possible so that you can add more fuel to it and thus make more power.

j_tso

iTrader: (2)

I'm most excited over that fact that it's going to be all aluminum.

NSU tried that back in the 60s and saved almost 80lbs on theirs, so with modern casting it could be more, and there was a blurb in Automobile for the rotary's 40th anniversary that showed Jim Mederer with a 180lb 300hp peri-port 13B.

Hopefully, the lighter engine will be put into a lighter car.

zeroecco

the weight savings i amazing when you look at it, placing these new motors in sub compact cars would greatly reduce the extra weight and get us closer to the sub 2k weight range again for small cars. When you weigh out the current renesis versus the older rotaries you'll find alot of weight savings, I look forward to and even lighter and higher torque rotary.