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The Renesis exhaust should have a significant flat line at peak area and the intakes should be a flatter curve at the top. Otherwise , yes, it does approximate what is taking
place.
knew I had seen it before; here you go, this should be more to your suiting
more accurate port timing comparison between Renesis (bold line) and the REW engines.
which many people fail to recognize the the flow characteristic difference between this and a bridgeport wrt timing. Simply considering the amount of timing overlap is not really relative to what’s actually occurring and is entirely different in influencing the end result.
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so, here’s an example of how things often aren’t looked upon and seen clearly with a critical eye to comprehend and understand that which is before them.
starting with this image, what’s really going on here?
1. Observe and see first that the 13B peri exhaust port opens before the Renesis side ports.
2. Next, that the 13B port is opening fairly quickly, almost 2/3 of the way to being fully open (flat horizontal line indicates full area of port open) at which point the Renesis side ports begin to open; the first red vertical line. So the combustion gasses are rushing out the 13B peri port starting to form a pulse, but are then interrupted by the Renesis exhaust ports beginning to open. The side port opens about as fast as the peri port. What does this mean? So the pulse was forming in the peri port, but when the side ports open now the flow is split into three divided streams, each now with reduced velocity and energy; three weak separate pulses.
3. At the second red vertical line it can be seen that the peri port is now fully open, but the side ports having more area continue to open further until also being fully exposed. So the side port pulses continue to gain energy at the expense of the peri port pulse, yet all divided.
4. Then observe that all three ports are fully open with the combustion energy distributing through those three paths, likely not equally. Except this combined area of all three ports can easily support significant whp without any modifications. Quite excessively so. The obvious conclusion is to seal off the Renesis side ports efficiently. Assuming that can be done without trapping excessive combustion gas pulsing in/out the port cavities if only sealed at the exhaust flange, or if filled; pieces of the sealing material breaking loose over time from vibration and heat stress fatigue to then fall back into the rotor and destroy the engine, it could address the excessive area and divided chaotic flow streams. However, it doesn’t address other things that are coming later in the cycle.
5. Next to observe; the side ports start to close while the peri port continues to be fully open. The question; is there any combustion pressure left to flow out through all that area? Or is it maybe stagnant or even reversed and flowing back in? That’s more likely at low rpm than high rpm. Regardless, now the two side port streams are closing off. In fact, we can see at the 3rd red vertical line the REW port is still fully open until right near where the Renesis side ports finally close off at the 4th vertical red line.
6. The last red vertical line occurs at 48° ABDC on the OE peri exhaust port. Now go to my previous post above and and observe how Mazda both increased the Renesis primary and secondary intake port area, but also that larger area positioned toward the outer housing surface results in them both opening much earlier too. On a Renesis the primary port opens almost immediately; 3° ABDC and the secondary also very, very early in the intake cycle; 12° ABDC. Here again, many here don’t understand that even the largest full-ported 13B primary port doesn’t open until much later. The same for a fully-ported 13B secondary port.
By bridgeporting the 13B ports the opening can be increased to occur much earlier though. However again, most people don’t understand how a bridgeport being opened is much different than how a repositioned full port opens. When the rotor tip initially begins to passover the bridgeport eyebrow, that narrow opening is only slowly opening until the rotor tip passes by the entire length of it to then be fully open. At which point, if you imagine it being plotted out like the image above, the open area curve will flat line. So the eyebrow is fully open, but it’s small; long and narrow. Then there’s no change in area as the rotor continues to rotate and expose the bridge. Only after the face of the rotor comes past the bridge does more area for the main primary port begin to open.
With the Renesis primary though, instead of it slowly starting to open, the full side of the entire port opens at 3° past BDC and continues to open; there’s no pause or delay or slowness. By the time a factory unported 13B peri exhaust port finally closes at 48° past BDC; 45° of duration following when the Renesis primary began opening, the Renesis primary port is substantially opened and exposed. It’s just not the same thing. So then when somebody starts talking about overlap timing comparisons and implying it’s all the same then you should now know that they don’t really comprehend or understand what is actually taking place.
So the questions that might need to be considered are:
Is clean air flowing in from the intake or are combustion gasses flowing in from the exhaust cycle? Better yet, are combustion gasses back-flowing into the intake manifold and not only displacing clean intake air, but also defeating resonance features? Consider also in the case of all the exhaust ports open and flowing, the amount of open area and flow capability relative to the flow being generated by the power output means that the combustion energy and flow likely ended much earlier than before the ports close. And without any true pulse to tune for near closing, the case for considering that the intake cycle is more likely to ingest exhaust in than clean atmosphere should be obvious.
It’s understandable that people struggle to understand all of this. Because there’s a lot to get your mind wrapped around and keep track of. You have to know and understand what a Renesis engine is, why it is, and what distinguishes it from a 13B engine. A Renesis is a similar 13B engine that when fully optimized and functioning properly will generate 270 bhp @ ~8200 rpm naturally aspirated, while being quite civil for low speed street use and being much more emissions compliant. Dyno graphs are posted on the forum that demonstrate this. However, what are the conditions that it accomplishes this output level? First, it does it without any exhaust/intake port timing overlap at all; absolutely none. Second, without overlap this means it also does it without any exhaust resonance tuning at all; absolutely none. Third, this also then means it does it entirely on intake tuning resonance; the truly critical feature that makes it all possible.
There’s much more to discuss and go into, but I’m going to stop and pause here. Because it’s just too much to absorb in one sitting. The thing is, when the peri port exhaust housing is introduced into the mix, *all* of those items I just covered in the previous paragraph are all being messed with. Clearly many people are not fully grasping the realities that messing with them is going to result in. It’s not as simple as; Immagunna add me a bunch of overlap and make enough power to stop the world from spinning.
.
"A Renesis is a similar 13B engine that when fully optimized and functioning properly will generate 270 bhp @ ~8200 rpm naturally aspirated, while being quite civil for low speed street use and being much more emissions compliant. Dyno graphs are posted on the forum that demonstrate this."
It blows my mind that after all these years no one has figured out how to reduce the optimal drivetrain loss below ~23% in this chassis. I realize that the compounding effects of higher rpms really hits us hard in this aspect, and maybe nothing in the drivetrain can be much more optimized without incurring overheating and reliability issues such as looking at the diff.
It's just surprising to me, I know there's probably guys out there with efficiency tricks that haven't shared this info yet
no, the issue is that most Renesis engines have too much seal leakage and don’t make anywhere near that output. Low 230ish whp is possible in an RX8/Renesis. It has a cost factor though. Just as the engine you see KMR building is much more expensive than most people here realize. It’s probably 2x what it would cost to buy a rebuild motor from Mazda. And will suck as an NA motor.
Diyman25 should be able to at least acquire and post an idle vacuum @ rpm reading for the engine this thread is about. That will reveal plenty imo.
.
Just keeping the thread updated. None of my computers at home are allowing pictures from this site or some others. I think it's my VPN.
Work, no problem, but I can't devote enough mental time for this thread at work.
so you updated the thread to let everyone know about the blessing you’re not perceiving?
maybe devote a sliver of mental time to this; how hard is it to make a log and post the data compared to making and posting up videos and words for enticing flesh and blood. 🤔
.
Ported N/A Renesis thread/Builds remind me of "1000whp" build threads on the Mitsubishi 3000GT Forums
*Pictures of Shiny Parts
*Hype
*Start up/Free Revving Video
*More Hype
*False Claims
*OP goes AWOL
*3 Months of Arguing
*OP Returns with engine in pieces
Coming Soon?
*Link to Part out thread
*OP Buys Corvette
Last edited by blackmount; Aug 29, 2022 at 10:54 AM.
so, here’s an example of how things often aren’t looked upon and seen clearly with a critical eye to comprehend and understand that which is before them.
starting with this image, what’s really going on here?
1. Observe and see first that the 13B peri exhaust port opens before the Renesis side ports.
2. Next, that the 13B port is opening fairly quickly, almost 2/3 of the way to being fully open (flat horizontal line indicates full area of port open) at which point the Renesis side ports begin to open; the first red vertical line. So the combustion gasses are rushing out the 13B peri port starting to form a pulse, but are then interrupted by the Renesis exhaust ports beginning to open. The side port opens about as fast as the peri port. What does this mean? So the pulse was forming in the peri port, but when the side ports open now the flow is split into three divided streams, each now with reduced velocity and energy; three weak separate pulses.
3. At the second red vertical line it can be seen that the peri port is now fully open, but the side ports having more area continue to open further until also being fully exposed. So the side port pulses continue to gain energy at the expense of the peri port pulse, yet all divided.
4. Then observe that all three ports are fully open with the combustion energy distributing through those three paths, likely not equally. Except this combined area of all three ports can easily support significant whp without any modifications. Quite excessively so. The obvious conclusion is to seal off the Renesis side ports efficiently. Assuming that can be done without trapping excessive combustion gas pulsing in/out the port cavities if only sealed at the exhaust flange, or if filled; pieces of the sealing material breaking loose over time from vibration and heat stress fatigue to then fall back into the rotor and destroy the engine, it could address the excessive area and divided chaotic flow streams. However, it doesn’t address other things that are coming later in the cycle.
5. Next to observe; the side ports start to close while the peri port continues to be fully open. The question; is there any combustion pressure left to flow out through all that area? Or is it maybe stagnant or even reversed and flowing back in? That’s more likely at low rpm than high rpm. Regardless, now the two side port streams are closing off. In fact, we can see at the 3rd red vertical line the REW port is still fully open until right near where the Renesis side ports finally close off at the 4th vertical red line.
6. The last red vertical line occurs at 48° ABDC on the OE peri exhaust port. Now go to my previous post above and and observe how Mazda both increased the Renesis primary and secondary intake port area, but also that larger area positioned toward the outer housing surface results in them both opening much earlier too. On a Renesis the primary port opens almost immediately; 3° ABDC and the secondary also very, very early in the intake cycle; 12° ABDC. Here again, many here don’t understand that even the largest full-ported 13B primary port doesn’t open until much later. The same for a fully-ported 13B secondary port.
By bridgeporting the 13B ports the opening can be increased to occur much earlier though. However again, most people don’t understand how a bridgeport being opened is much different than how a repositioned full port opens. When the rotor tip initially begins to passover the bridgeport eyebrow, that narrow opening is only slowly opening until the rotor tip passes by the entire length of it to then be fully open. At which point, if you imagine it being plotted out like the image above, the open area curve will flat line. So the eyebrow is fully open, but it’s small; long and narrow. Then there’s no change in area as the rotor continues to rotate and expose the bridge. Only after the face of the rotor comes past the bridge does more area for the main primary port begin to open.
With the Renesis primary though, instead of it slowly starting to open, the full side of the entire port opens at 3° past BDC and continues to open; there’s no pause or delay or slowness. By the time a factory unported 13B peri exhaust port finally closes at 48° past BDC; 45° of duration following when the Renesis primary began opening, the Renesis primary port is substantially opened and exposed. It’s just not the same thing. So then when somebody starts talking about overlap timing comparisons and implying it’s all the same then you should now know that they don’t really comprehend or understand what is actually taking place.
So the questions that might need to be considered are:
Is clean air flowing in from the intake or are combustion gasses flowing in from the exhaust cycle? Better yet, are combustion gasses back-flowing into the intake manifold and not only displacing clean intake air, but also defeating resonance features? Consider also in the case of all the exhaust ports open and flowing, the amount of open area and flow capability relative to the flow being generated by the power output means that the combustion energy and flow likely ended much earlier than before the ports close. And without any true pulse to tune for near closing, the case for considering that the intake cycle is more likely to ingest exhaust in than clean atmosphere should be obvious.
It’s understandable that people struggle to understand all of this. Because there’s a lot to get your mind wrapped around and keep track of. You have to know and understand what a Renesis engine is, why it is, and what distinguishes it from a 13B engine. A Renesis is a similar 13B engine that when fully optimized and functioning properly will generate 270 bhp @ ~8200 rpm naturally aspirated, while being quite civil for low speed street use and being much more emissions compliant. Dyno graphs are posted on the forum that demonstrate this. However, what are the conditions that it accomplishes this output level? First, it does it without any exhaust/intake port timing overlap at all; absolutely none. Second, without overlap this means it also does it without any exhaust resonance tuning at all; absolutely none. Third, this also then means it does it entirely on intake tuning resonance; the truly critical feature that makes it all possible.
There’s much more to discuss and go into, but I’m going to stop and pause here. Because it’s just too much to absorb in one sitting. The thing is, when the peri port exhaust housing is introduced into the mix, *all* of those items I just covered in the previous paragraph are all being messed with. Clearly many people are not fully grasping the realities that messing with them is going to result in. It’s not as simple as; Immagunna add me a bunch of overlap and make enough power to stop the world from spinning.
.
Dyno chart add
Last edited by kevink0000; Sep 27, 2022 at 07:52 AM.
Friend took it to Dyno
Without tune , and with factory air box
Car made about same HP like stock 13B MSP
But mid range TQ is about 2Kg higher then MSP
When I test drive it back then , it does feel more TQ then my
He did not take pic
But I remind him there is big argument here
So be sure taking pic next time !!!!!!
but ..................... Kg is a unit of mass........... not torque.
And 2 Nm of torque is almost nothing so I'm trying to understand what the measurement really is. If you say you can feel it ..... it's got to be a lot more than 2 Nm.
but ..................... Kg is a unit of mass........... not torque.
And 2 Nm of torque is almost nothing so I'm trying to understand what the measurement really is. If you say you can feel it ..... it's got to be a lot more than 2 Nm.
Every country have their own measurements
If is only 2NM I won't bother to post here
Kg of torque was until some time ago the way specs were published in Greece. And other eu countries. Now it has faded, apparently for the reasons stated above. But we boomers, still use kg for torque. So I guess there's a misunderstanding here.
