well that looks like a multi plate clutch... maybe SPEC... idk but its part of whatever clutch kit that is.

 

Quarter Master V-Drive 2-Disc racing clutch. http://www.mazdatrix.com/r-clutch-flywheel.htm

 

just wondering,

what happened to the procharger kit?

beers

 

you are a 1 man fubar machine, read the thread and learn how to search again, and please don't feed the noobs


.

 

really,

i think it is a real great question as to where the pro charger with the rick shaw tuner went?

now i have been gone for a while. and i i am a one man fubar machine. maybe pm me before you change things.

dont no dick about dick.. but really?

beers

 

it's been boring as hell around here lately so I'm in the mood to pull an OD and throw this out since I already discounted the idea a long time ago, but you guys love to hash over this kind of stuff

What if you plumb the center Renesis port (or block it) and the PP ports to the turbo and then mount a wastegate at the exhaust flange at each Renesis side exhaust port ...

 

You, OD, and this guy walk into a bar...

 

I'm famous!

 

 

That sounds like a complex system--what would be the advantages?

 

did you see the 5-pipe manifold? That is both complex and ugly, if not grossly excessive.

there are disadvantages too, what do you think they are?

 

about to pull my gsl-se engine and make a 5 exhaust port.. but my idea is the opposite...


run side exhuast to half of divided turbo, run the two peri exhaust to.. waste gates, or some sort of butterfly? valve, to keep them closed under ~4000 rpm, after the wastegates, or valves, it goes to the other half of the divided turbo..... package will be the challange, and top mount is assured.

drive ability of the stock rx-8 under 4k, and a beast after?

Flame on!

 

the peri-exhaust is fine for turbo use all on it's own and you still end up with all the same side-exhaust issues

 

Doesn't that mean you will effectively have no wastegate at all ? Could see some huge engine destroying boost early on .....

 

no, his idea is based on having a butterfly that keeps the peri-exhuast ports dedicated to wastegates up to a certain rpm and then opening the butterfly so they can feed either the turbine or wastegates is some kind of advantage, which it's not. The overlap still occurs whether the port is flowing outward or not.

the problem with either idea is that the static port volume becomes a cavity of stored heat and pressure energy. The end result will likely not bode well in the long run.

 

I cannot resist the urge to jump in. However, I see one major flaw in this cool idea.

I originally thought about this too, but after further thought, I decided that low end driveability will still be severely affected.

My reasoning is as follows:

Once you go PP exhaust, the largest thing affecting low-end is overlap. By putting something in the way of the PP port, you will increase backpressure for that port. More exahust will travel back in and therefore the adverse affects of overlap will be increased.

wrong?

 

would the centerport relieve that ?

 

i too, see these.. "failure points" but i still wanna try it .. just to see, and then find ways of over coming the failures the "prototype" will produce.
if only i could put the "valves" right up against the exhaust port(inside the rotor housing, like 4 mm from the rotor itself). maybe we just need a valvetrain.... so much for "just 3 moving parts"

 

Stumbled onto more pics of MazdaTrix's engine today

 

Looks like a plumbing nightmare!

 

I've gone through two and on my third MOP because of my set up. The third one has so much shielding on it but I still feel uncomfortable. I wonder what resolutions mazdatrix has for this set up.

Racing was originally used to explorations the limits and continue development in an extreme environment. I applaud Mazdatrix for their resolving to work with the Renny and not just throw a REW like most other racing teams have done. I however feel it might not matter for if its not house involved (mazdaspeed) it would not mean anything for rotary engine development we could see in future RX cars.

 

Looking good great turn out

 

lol, can’t recall posting that, might have gotten the idea from Brettus. I might even instead say to instead have two manifolds now; the two peri exhaust ports to the turbo and all the side ports to a wastegate. It might actually work except ...

that having ideas based on shooting from the hip and fully understanding in detail what makes things tick, or not, can often be quite different in the perceived and actual outcome. So just throwing 13B housings together with Renesis plates might seem like a good idea.

I even thought so myself at one time. It all comes down to port timing though. Mazda didn’t just reduce exhaust overlap on the Renesis. They rotated a lot of the intake and port timing events together. Not just closing the exhaust port sooner, but opening the intake ports sooner. A lot sooner for both.

So on the Renesis there’s no intake-exhaust overlap at all. On the REW, which has the same exhaust opening timing as the GSL housing; so I’m going to focus on the REW timing as a comparison, it has some overlap. It’s not a lot, but some.

REW
Primary port - 3 deg overlap
Secondary port - 13 deg overlap
APV port - N/A

Because Mazda phased the REW intake port opening points away from when the exhaust port closes to minimize overlap. With the Renesis they did the same thing, which is they closed the exhaust port a lot earlier, and then opened the intake ports a lot earlier too. So when the peripheral exhaust is added it doesn’t just add some overlap. It adds a LOT of overlap. Like peripheral intake port amount of overlap.

So most people are familiar with this comparison between the REW and Renesis ports from the Renesis SAE paper.





However, the scaling is such that the detail at the overlap point is not readily seen.




Which you can see it in the timing events if the effort is made to do that. So what happens when the 13B housing and Renesis plates are combined? Well I’m going to compare it against the MFR factory peripheral intake port paired with the REW housing. In reality, the exhaust port is opened more for racing with added overlap, but this is with the unmodified exhaust port with OE closing


Renesis with REW housing
Primary port - 45 deg overlap
Secondary port - 36 deg overlap
APV port - 20 deg overlap

MFR PP with REW housing
P port - 58 deg overlap


Note that the P port opens 13 deg earlier than the earliest Renesis intake port, but has the same closing point as the latest Renesis intake port. So what Mazda has done with the Renesis is create intake timing similar to a P port, but with the staged S-DAIS intake manifold system to greatly improve drivability. Plus, they did it with no intake-exhaust overlap. On the Renesis there’s 6 degs timing between when the exhaust port closes and the earliest intake port opens.

I’m coming to the conclusion that this has a lot implications that likely weren’t ever realized before. It’s been well accepted that the common scavenging intake theory applies well to the Rotary engine, yet Mazda achieved power on the Renesis without it. Even without the S-DAIS intake system the Renesis excels above a 13B.



So it seems there’s more going on with this than was ever previously realized on a rotary engine. Almost as if there are two entirely different methods to achieve rotary power output now. So where is all this going? If we’re essentially pairing a P port intake; and staged one at that, with a P port exhaust, then herds of unicorns and lucky charm leprechauns ought to be flying out of the exhaust pipe, right? Unfortunately life isn’t that simple.

With the 13B housings a lot of overlap is added and as we saw previously, it’s added the most on the primary ports, which are never closed off, and then more coming in later with the staged Sec and APV ports. So in that sense it’s more like the race P port intake. However I concluded and have stated before that the real spoiler is the side exhaust ports.

The scavenging port flow theory is based on tuning exhaust pulses to time them with the intake ports opening to scavenge out the last of the exhaust gasses and replace them with fresh intake A/F. The problem is though, that with both the side and peri exhaust ports together it greatly increased volume, which in turn reduces velocity, but it’s also broken up into three separate streams rather than in one concentrated pulse stream per rotor. That more or less kills scavenging; lot’s of overlap, no scavenging, and then the logical extension is, lots of exhaust gasses recirculating into the intake cycle. However, scavenging mostly applies to normal aspiration. once FI is introduced it changes. In my estimation, the Renesis-13B hybrid concept for NA is never going to work for these reasons.

So ok, we just throw a turbo on and get ready for the sudden rush of unicorns and leprechauns, right? Not so fast. Yes, a P port setup can make big power with a turbo, really big power, but only under certain conditions. The big benefit of a P port is that it can be extremely efficient, quite a bit greater than 100% even, but generally within a narrow operating range.

You can stage a Pport similar to what the Renesis S-DAIS intake does, i.e. the infamous 26B 4-port LeMans engine. However that was all done integrally with sliding trumpet runners. It’s accomplished some with the S-DAIS intake, but the port runners are never going to shorten and free flow up enough to achieve that kind of efficiency. It’s all that drag from the runner wall length holding it back.

The other thing is, a P port intake is very sensitive to backpressure. Even with the drivability issue aside, the problem with running one on the street is the exhaust noise because it has to flow freely for the scavenging to work properly. Except we throw scavenging out the window with FI. What you then have to avoid is turbo manifold backpressure. Also, while overlap is good for scavenging, that amount of it for turbo is not good. The goal is to fill the chamber, combust it powerfully, and then get it out, rinse an repeat. Too much overlap and too much backpressure with a turbo is simply creating the NA condition; excessive combustion gasses going back to the intake cycle.

So my final conclusion is that potentially big power can be had with this using a turbo; a really big turbo. A small turbo with a tight turbine isn’t going to cut it at all. It needs a big turbo with a big A/R. You need to be thinking EFR 9174/80 with 1.45 housing or equivalent non-EFR without modifying the exhaust port timing, set up with E85, high boost and high rpm. Think Scoot Japan kind of power and rpm. That’s my current conclusion any way.
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.

 

Nice write up. Also something to consider along the same vein , zero overlap on a Renesis means it is less sensitive to EMAP than an REW is .................

 

yes, I said in the exhaust port thread that it’s actually a benefit up to a point. We totally agree on that