So i should just take his word for it that it's just too complicated, you know from the talk is cheap guy. Yeah no thanks.

I was never referring to brettus, he's been decent in everythread he's posted in that I've seen.

I'm not here for help, and one way or the other I will try both methods as a starting point to see which gets me closer to actual. It's how you learn, it seems as though very few if any of the people that are responding have tried it, and at least one guy has successfully tuned this way. So yeah, having fun. If your not leave.

Dogon, I don't think anyone saying that it's impossible or black magic. Simply that you have to set aside and ignore prior assumptions and knowledge and learn from the ground up. Yes, plenty of knowledge will transfer, but you need to know what does and what doesn't, and why. Just handing you a list of what transfers and what doesn't won't really help you since you still need to understand why for each point. Going into it with the same assumptions from piston tuning will cost you a motor, and being stubborn about it won't magically remedy that problem.

"Another great example showing you do not have the knowledge base to continue further, yet you do!
Only a handful of cars utilize a variable intake tract like an RX8, it was never previously used on any production rotary. Nor is it common on any other type of production car on the road until you get into the high end performance category. Are you even away of how it works? contrary to your belief it does not work like your vtec did. "

rsx's do I think there are a couple others but your assuming a bit much.

"Unless you have a vacuum leak post MAF, their is no logical or feasible reason why the MAF would not know exactly what has passed it, its flowing in a closed system, it knows the temperature and the weight. That will never change (of note testing has been done and the MAF vs actual air temp right before it enters the engine varies arguably at about 3 degrees, not going to make much difference)
Also the engineers that wrote the VE table did indeed know the exact data, unfortunately it was not using Cobb or any other aftermarket tuning software available to the public, we have no control on how this data is pulled off the ECU and displayed to us all we know is that the values are not a direct relationship."

But every 8 is unique, and no it isn't much but that is a calibration table, so why not use it? You know your maf isn't off by more than a percent, but you re calibrate that. I'm not talking about exclusively tweaking the ve tables. Are you arguing the Ve table is bang on? No coast was saying that table isn't calibrated very well on our cars, and from the brief tweaking I've done with it I agree. Why do you disagree?

"MAF tuning is far superior to MAP based tuning solely for this reason alone Its statements like this that prove you have very little experience in what you are trying to appear to be knowledgeable of."

I've never claimed to be an expert, or even to have the answer. I mentioned my experience because I don't need basic concepts thrown back at me. I know maf is superior to map, but if the table your maf is referencing is 3% off and your maf is only 1% off the error you are seeing sounds to me like it's the fault of the table. if that's not the case why not?

"Per Mazda specification and specification of the distributors, these sensors have a tolerance of up to 20%. Hence the need to calibrate them, for the everyday driver the OE tune is conservative and almost auto correcting resulting in a mute issue. The car will function properly and will not throw a CEL and resort to limp mode unless a variation of more than 20% is achieved."

I'm aware the maf needs to be calibrated that isn't the issue here. My last maf went -18 ltft without throwing a code, but it was definitively a bad maf. 20% differences on a new maf is something I have never seen. I'd be interested to hear of anybody who has looked at a lot of these on any car where out of the box the variation was more than 5%.

"VE plays to little role in an RENESIS because of its nature, the exhaust port is the limiting factor. Intake and exhaust aside NA you will never be able to increase this more than a couple percent unless you get into exhaust porting in which case you will be going through rebuilds ever 20-30K miles as well."

I get that, but like every table on the car, it's off, that's all I'm saying, I don't see how you could achieve superior tunes by not adjusting it if that makes sense.

"Cobb base maps are MAF tuned and run to lean on any engine you through them on regardless of stock or modded so no one ever uses them anyways. Also they say not to use it because it is MAF based and intake mods require you to recalibrate your MAF. Thusly leading a very use less tune to begin with even worse off.
At the end of the day tuning an NA RENESIS is not difficult, in fact you have to actively try to mess it up. I agree with some of you points regarding MAF tuning an AFR spikes it is what plagues most FI engines and leads to catastrophic failures due to pings. The fact still remains, the number we get and can adjust are arbitrary in themselves, we have no idea what the real values are as we do not have access to the tuning software that wrote them nor have any control on how any of the tuning software we have available interprets them. Because of that and the fact the VE on a RENESIS is limited internally (hence mods have no effect on it) their is very little to be gained from changing the VE tables but have an engine to lose if it gets messed up. This is why no RENESIS tuners that are proficient enough touch this table, in fact all of them highly recommend against it. The benefit to risk ratio is just not worth it"

Yeah when I say VE tuning, I'm not talking about using this table to make power. In fact you can't ever get this table perfect there isn't enough resolution. I'm talking about doing this in conjunction with maf scaling to make a base. I'm curious as to which you would start on to be closest to commanded but that's going to take trial and error unless someone here has done it. On a boosted car yeah, I wouldn't touch it either, but I've never brought up boosted cars, and my car isn't boosted. VE actually does change with boost, and that table isn't designed around a boosted car so yeah without drilling down to figure out exactly what those numbers effect I wouldn't risk it. But that's not where I'm at, and that's not what no coast was talking about. Your right mods on our car do little to effect ve, which is why re calibrating this table is perfectly reasonable if your N/A, all your doing is fixing our ecu's one size fits all approach. Our engines are highly variable from one to the next compared to many others, so there is no reason this table would be correct. Boosted you can't take the risk of playing with it, I get it. But I'm NA, I'm gonna play with it, I wouldn't if anybody else has done both and compared the two, and demonstrated it being ineffective or dangerous, or if it would even swing due to environmental effects, but as far as I can tell no one has.

Your really just not getting the point :wallbash:

VE is limited by inherent design of the RENESIS, we do not know what the values shown to us actually represent, so why risk changing something that you will gain very little from when you do not understand the incremental change in our PCM. How the PCM reads VE changes is not the same as how they are shown in Cobb

I have adjusted my VE table, and yes their are instances that it is needed. My application was due to the port work I had done, but 99.9% of the cars out their will not see much benefit from changing this table it just does not account for a whole lot and changing it without caution is very reckless. Myself and my tuner changed it as a last resort due to a lean issue i was having mid range. We did it in very small increments while meticulously monitoring what else it changes.

Tuning a RENESIS, you need MAF, Injector scaling, A/F, and timing. that's really all you need to worry about. Yes you can take it further but it just is not worth it, you have to little to gain and to much to risk.

Please show me where an RSX has a variable intake? SSV? VDI? APV, VFAD? Do you understand how these change the dynamics of the intake?

Tuning a RENESIS, you need MAF, Injector scaling, A/F, and timing. that's really all you need to worry about. Yes you can take it further but it just is not worth it, you have to little to gain and to much to risk.

Because it's pretty easy to measure the results. And that's how you figure things out, you test, observe, and collaborate. Obviously a 10% change in a cell on the ve table doesn't effect fuel by 10% but it does have an effect, and it has more resolution than Maf scaling.

It may only be on the type s but they have dual intake tracts actuated by a solenoid. Hell I'm pretty sure the late model gsr's had them too, but Honda and Acura are not the only small cars that use them.

The fact still remains you are talking mechanical characteristics of a piston engine and apllying them here. VE just does not change. If you had a factory LSX and where doing tuning, would you worry about the VE tables or take the tables generated by the manufacturer who did more testing on it then you ever could imagine to understand.

I don't understand the idea of ve tuning unless you have no other option. I do agree that you have to use it. it can be very critical for tuning out lean spikes caused by the apv. Heck i even suspect that is what brettus is doing since he raised his ssv opening.

Volumic efficency is how much air the engine can hold.

The renesis is 1308 CC's if your ve is 100% then you are at 1308 cc's of air. If the engine just can't get full for some reason then your ve will be less. Even with FI it doesn't change the VE of the engine it changes the pressure in the engine. Now for a ECU without pressure compensators built in you have to make due with what you have.

Lets just say that you can do a mod and get a 10% increase in power. If you change the VE table you're telling your car that your engine is now 1438 cc's. Your engine did not get bigger. So why are you telling it that it got bigger. Even the most worn out engine ever will only gain a few cc's. any more then that and your going to wear into a water jacket. so lets say you're worn it out by 5 cc's that's only 1/3rd of 1%. You can't even make a change that small to the table.

Even if you are pulling in 10% more air. the MAF will see the extra air and add extra fuel to compensate for it.

Load is a calculation of the measured air intake volume, the true VE of the engine and the RPM. I don't know the exact calculation, but oltmann has posted it around here somewhere. THE VE is already figured into the load.

What risk? I'm not talking about a FI car. How could you possibly do damage if it gets you closer to commanded, and if it's as no coast observed, dead on commanded? It may not be the best way, but it also doesn't sound like anyone here has actually tried, or seen it done, so how do you know? The guy that has, says it works, and I started playing with it yesterday, but I'm sure as hell not seeing anything dangerous. and a couple cells have been changed around 8%. Closer to commanded, and runs smoother, and a more stable idle. I'm sure I could achieve the same with maf scaling, but nothing close to dangerous is happening here.

Yeah but a 10% change to that table obviously doesn't mean the ECU thinks ve changed by 10% because even on the stock map most of the cells are above 100%.

We know our tables are widely off, and each 8 is very unique, which is why you can't chip one. Piston engines are not as unique as ours and that's why in a civic flashing is enough for most people. I mean why do you run two oils? engineers fuck up or hedge out of necessity all the time.

I know that, I was just commenting about ve tuning in general. That map is not a ve map. I've said that a few times.


It is used to make smaller more accurate "pinpoint" adjustments. It is not even the same base idea as VE tuning.

The true VE map for the car is not accessable with the Cobb Accessport.

I don't have the table infront of me at the moment but considering the dynamics of the intake depending one the RPM in which cells VE is over 100 I could see it plausibly.

These are the things you are dealing with you just don't know, and who said out VE table is not correct? Your saying Mazda was incapable of figuring it out with some of the best engineers in the world?

As Logan and I already stated it's not a real VE table.

Yeah I agree, but ideally why wouldn't you see which of the two tables is off the most and adjust accordingly? I know my maf or any maf is going to be off by 1-2% ideally, but if I have to adjust it by 5% to account for the ve tables being off why not take some of that off or add to the ve tables? I am still going to have to adjust the ve tables one way or the other to smooth it out. This assumes my injectors are bang on of course. If my maf is reading dead on spec, but I still have fuel trims, correcting with an across the board maf scale is really just a band aide. You can change how the maf reports, or change it's interpreter. In reality both are off, so both need changing.

OK it's established nobody thinks it's actual ve.

It's not correct, because its an arbitrary number, and you can't make any table for this car that will be accurate across all of them, which is why we need specialized tuning. And it's pretty easy to observe by playing with the tables. Other people use it for fine tuning which suggests it is indeed like all our other tables, a compromise the engineers and lawyers could live with. I mean name another engine that routinely craps out before a 100k. And stubbornly clinging to those piston concepts didn't blow up no coasts engine. What he obsserved wasn't radically different than what he was expecting, or at least he didn't mention it, so I really don't have any reason to doubt anything he said. So I dunno, there is a lot of evidence it's wrong.

Tuning and VE tables do not contribute to appex and coolant seal failure that effect longevity.

I actually don't think I ever heard of an NA engine failing because of the way Mazda tuned the engine. In all actuality the OE tune is very good.

It's damn near impossible to blow a NA Renesis up with a bad tune. The failures modes vary are usually not singular but they are definitely not tune related. That was proven when the OMP rates were increased and the failures still continued. You guys are wasting your time trying to make him understand.

Yeah my point is simply that engineers get things wrong, or make compromises all the time, this car isn't any different. Looking at the stock tables it's pretty clear most if not all are compromises and one size fits all solutions to keep an engine with a wide range of production variation in check.

Name one production for the everyday driver that was not tuned comservatively?

You say Mazda did a crap job, based on what? The facts remain the same an NA 8 does not benefit much from any aftermarket mods. Intake, exhaust, tune etc... And maybe just maybe you will see 10-12whp above factory. Yup that sounds like Mazda made no effort to run this engine at peak performance. My OE tune I was 14.7 AFR cruise and almost dead on 12 AFR explain to me where
Mazda went wrong?

Now you are not only claiming you can tune your first rotary, but you can do it better than the company that pioneered the technology.

How do you not see the arrogance?

Strawman much? All I said is it isn't perfect, I'm not claiming it's shit either. If it's so damn perfect why do you tune at all? Why aren't there chip tunes? You know the answers to these questions and you know what I meant. I never claimed I could do it better. There's no reason for you to be so damn tedious. Grow up.

Nothing is perfect, and to expect anything less from the manufacturer is asinine, but to say that compromises where made on this car when in reality they where not. Even from a tuning aspect it was dialed in from the start.

Chip tunes? If I have to answer that you really don't understand how complex our PCM really is.

As far as why people tune (respectively NA only) heres the main reasons

-Rebuild/Port work
-Better MPG (meaning they are detuning to get less performance)
-Intake/Exhaust Mods Tune to support MAF changes
-Throw a P0420 Code, buy a cobb to mask it, for the extra 300 bucks they tune it as well just to get a couple more HP.

Fact of the matter still remains no one is looking towards NA RENESIS and creating much more power than from the factory, you just physically can't do it. The most I have seen is 20 WHP from a speedsource car that was using all lighten internals, long tube header, Speed source Pulley w/ AC delete, MS intake. I also believe they had all their internals coated to reduce friction, and I think port work. All in all over 15K invested into an NA engine to get 20WHP.

A reliable FI kit is cheaper, and thats saying something.

240WHP was the norm on the Koni challenge cars but that is not comparable to what we are talking about here.

So what you're saying is our way is the ultimate.I mean there are plenty of posts by MM, a lot of which have been proven wrong, But his base of tuning still revolves around the MAF curve.

That was before my time here, regardless the details the investment they put in IMO was not worth it. It's cool for a because I can story but no real world applications with the average consumer.

Your way acknowledges deficiencies in the ve table. But yeah all I'm saying is it's something to look into and it's certainly not stupid. There's only one way to find out, and it sure as shit isn't sitting around here sniping at each other and speculating. If you have some sort of logs showing an issue with tuning the ve tables I'd love to see it and we can drop it one way or the other.

I am doing it to find out for myself, if that bothers anyone stay clear of me and I'll do the same for you. Sorry I dared question the unicorn herders around here, but nobody seems to have an answer of whether or not our horses are actually growing horns if you get my drift. If it bothers anyone that I am questioning something that nobody can coherently explain or offer any evidence for one way or another that's your problem not mine. We will know soon enough right? I'll stroke all your precious ego's with platitudes if I'm wrong. But until then it would be awesome if people could keep their personalities out of a pretty cut and dry issue. If I am an idiot you will be vindicated, if it works we all learn something. Deal?

you're the one who started trashing people with your very first post. Then when I tried to talk to you about it. all you did is demand proof and not listen to anything at all. even though you contridict yourself multiple times and can't provide proof of your own.

I'm still waiting on another VE table based on load and not Pressure.

What are you on about? I'm talking about zeroing trims here. My point is no two 8's are the same. Is that controversial now?

It doesn't matter if you can't make more power, if it doesn't dyno the same, it's ve isn't the same. Cause physics. We don't know the voodoo in that map but it is kinda ridiculous to say every 8's ve is exactly the same throughout all rpm ranges and loads.

I think you mean I started out by asking why someone trying to help people using pretty standard tuning theories was being treated like shit. I demanded proof from the guy making the accusation. Still haven't seen any. I've seen a couple of acknowledgments that nobody has any first hand proof.

And your wrong about corvettes, it sometimes reads map sometimes maf. There are others use the google.

Evidence was given, you either failed to comprehend it or refuse to realize it.

Somebody please tell no coast his car doesn't work.

https://www.rx8club.com/mountain-for...ssport-137463/

Check the post date on that. I clearly know nothing about AP tuning. I may be fairly new to the rotary world, but the physics behind an Otto cycle engine don't really change much.

I think a lot of the confusion comes from thinking that VE is the ONLY table I'm working with. It's merely the primary one. There are some places where MAF changes make more sense (lower flow velocities being one area). Tuning is a holistic thing. You can't simply change one variable and expect it to work correctly. VE is just where the majority of the work was done. Target tables were another. There were some small MAF changes as well.

I believe in fostering open discussion. Hell, I posted my damn map completely unlocked for the world to see. Do I have all of the answers? No. Do I have a lot of them? Yes. I've been tuning for a hot minute. Is there a lot of dogma and misinformation floating around? Hell yeah. Open discussions can clear some of that up.

VE WILL change on an NA engine due to mods due to changes in resonance in the intake/exhaust tract. Resonance is a huge deal. It's a big reason why Mazda went to all of the trouble of the VDI witchcraft. Anything that changes resonance will change VE. Simple changes in air/exhaust flow can also effect chamber filling.

I'm not here to have a discussion about fluid dynamics.

Just know that VE really really I promise does change with mods.

Boosted engines running the stock ECU is a big discussion for another thread. The approach will be radically different. This thread wasn't about a boosted engine. It was about trying to wring every last bit of power out of an NA setup.

I'll be in the boosted club soon. All of the off the shelf kits I've seen are crap. I've built plenty of inconel manifolds and have some ideas. Something in the GT30R range. Non intercooled. Blow through MAF. Small 5 gallon fuel tank in the trunk full of methanol. E-85 through primary injectors. Methanol through secondaries. All still controlled through the factory ECU/AP. It all hinges on my deployment schedule. It probably won't happen this year (I have a motorcycle to get running again). Definately will happen next year. Then we'll have a new thread about that can of worms.

I was having thoughts about a big nitrous setup, because everyone would tell me it would blow up and I was awaiting the lulz on the forum. The deal I had on a bunch of sweet direct port hardware fell through, and I decided I really did just need to suck it up and build more turbo hardware.

I've been playing with it. It has modifiers but it behaves completely rationally. Nothing crazy or unexpected happens. It appears to just be a fuel injector look up table. It's harder but you can tune out your trims using just that table.

The point was there's many ways to skin a cat, and some people are more interested in being internet tuff guys than helping the community, or being decent.

Thanks for your input though, I'll post mine in a day or two, that table is actually pretty usefull in the mid to high range. I see absolutely no reason not to use it. It's easy to chase your tail with it though if you don't watch how the load travels through the cells when deciding how to tweak it, and it's kinda shit at adjusting the transition out of low load areas.

My advice to everyone is use the table as part of your tune if your NA. If you want to figure out why, play with it and you'll see pretty quickly. People bitch endlessly about unstable idles, and surges throughout, and this is the table for fixing that. I didn't see a shred of evidence that this is a dangerous table. It's easy for anyone to see and I suggest people do. You'll learn a lot about your car, and a lot about some of these so called experts.

Such an exciting thread.

Quick Question, can I post dropbox links here? I'll have to post my maps, logs, and some graphs it would be easier to just throw them all in a zip.

More thoughts on the subject. It's easier to keep it open loop once you have the major spikes taken care of. Adjusting the tables was a lot more straight forward that way and confirmed there wasn't any major computer trickery going on. I'm tweaking just these tables to feel them out (something I would never do normally or consider a proper base) but it completely reflects what I would expect from this car. As the valves in the intake tract switch you basically treat that range as an entirely different table and cannot smooth into it if that makes sense.

If I were to just use maf scaling my Maf would be off by around 4% (give or take) when I go from open loop (I dropped the exit load to 0) back to closed loop, I would say the change is negligible enough to consider my maf dead on.

For a daily driver or on a track, it seems to me this method would give you more area under the curve, and therefore a quicker car. It also allows you to fine tune the areas you drive the most in. If you are going for peak power, or drag racing (wrong car for that) then it doesn't really matter and this is a waste. I'm not sure if doing this is taking power off the top, and I'm not going to pay to dyno it to find out, and I haven't compared it to a maf scaling yet, but since this allows much finer tuning, I would be shocked if maf scaling is superior in spite of this not being a true ve table.

When I post the logs and tables and such I'll have more to say. so far so good though, it's pretty close but it needs to be fine tuned (which will take more time than I have had) so it's more proof of concept, and I'd like to drill down into testing the function of the actual table than chasing perfect numbers over the entire range. That said for seat of the pants tuning, it's pretty damn close.

My tune is based off the stage 1
 

After all I changed, it is no where near what the stage 1 was to begin with.

Changed:
Fans
Injector size
Idle speed
Throttle fuel tables
A/F tables for gears 1-3 and 4-6
Lead and trailing ignition
VE tables
Dwell
MAF calibration


Those are the ones I recall off the top of my head.

:beer05: