I believe you meant narrowband. Again, the only difference between now and 9 years ago is the flex fuel sensor and programming rather than dedicated tuning maps.

are you saying the oem O2 sensor is narrowband or it's not a good wideband?

Its not a narrowband - its a 4 wire wideband.. from my communications with Andy the lead engineer at adaptronic the oem sensor is very hard to control heater wise and is relatively sensitive. Its recommended to use a standalone 02 vs the oem sensor but none the less an individual can get by with the stock O2 sensor. Dont let this confuse you with the lambda module as its a completely different design structure for the bosch 4.9 sensor range.

when i was tuning on pump gas, the oem sensor reading was very comparable to the wideband sniffer at the tailpipe, the tailpipe was a couple points leaner probably due to location. Versatuner log the oem sensor as Lambda values, not AFR.

It might be a semi-quasi WB at best, but I never really put a lot of faith in it.

I was referring to Shawn’s post previously. The NA Renesis should be tuned for around 0.89λ WOT regardless of E%. Using 0.78λ on gas is not only hurting power, it’s going to result in too much carbon deposits.

Does .89 lamda equate to 13.08 AFR? If so, is that basically Lean Best Torque, and does it produce more power at LBT than RBT? I was under the impression Rich Best Torque was ~.83 lamda / 12.2 AFR, or am I mistaken?

It’s not a piston engine. It’s not a typical rotary engine. It’s a Renesis and it’s uniquely special.

If anyone still has any doubts about the effectiveness of ethanol blends ...they should take a look at this :

https://youtu.be/6_DQPLihXfo

Interesting to refer back to this chart I posted a few years ago , looks much the same as the one he uses above .

https://www.rx8club.com/series-i-maj...4/#post4873018

An interesting observation for me is that the cooling effect is most noticeable with direct injection. As we don't have direct injection we can surmise that, for the Renesis, it would be somewhere in between the two charts he displayed.

His explanation mirrors my experience with ethanol blends over the years and it's why I really push the idea on to anyone that will listen wrt turbo conversions.

oh geez; that youboob guy, really?
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Yes. A "youboob" guy with an engineering degree with specific interests into the automotive realm.

What exactly are you trying to say? That he has no credibility ... that ethanol blends don't work .... that the earth is flat?

I like the "racy scent"

he’s no different than a lot of other people just like him who otherwise aren’t playing the youboob game seeking likes and clicks by regurgitating known and established information under the guise of “supplying content”.

There’s not anything new or different going on here. Which is pretty much the norm for that particular intraweb platform and this one too. It was well know even before this thread started in 2016 and it’s not mirroring your experience, but that of all the people who went there long before you did. I was running it back at least 11-12 years ago NA.

Not that I’m here to boast about it, but rather to support the point that it was before my experience too, which was before your own.

there are also better ethanol premix oils than that bump above.
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So what if it's not new? I found it to be well presented and informative. It is relevant and interesting for people reading this thread. I'll tell you what ...I'll delete the link if you can find a better explanation somewhere. Or do you want to make a video yourself ?

Nowhere in that video is he saying he discovered these characteristics about ethanol, or that he is the first to describe it. The point is he made a video explaining it, presenting it in his own style, in an easy way to understand.

I understand not liking the YouTube click bait, please like and subscribe, make me an "influencer", LEARN THIS ONE NEW TRICK ABOUT ETHANOL!!!, and associated BS that comes with the platform, but this video isn't that.

I see your discernment tank is still dry and unused.
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Here's a good video for you.

Just remembered I was going to make this point before Team so rudely interrupted with his unhelpful post.

If we take the above as being correct : For an FI Renesis ........... The biggest 'bang for buck' with the least amount of modification to fuel system and tune for us is going to be in that 20-30% ethanol content range. This also reduces the amount of premix you need and any negative side effects/deposits from running ethanol + premix.
https://cimg7.ibsrv.net/gimg/www.rx8...e5b708b5c1.png
Chart showing chemical octane advantage only. (copied from link to "uboob guy" above)

https://cimg8.ibsrv.net/gimg/www.rx8...d1e7a03cf0.png
Chart showing chemical advantage in purple and total advantage (chemical plus cooling in DI engine)

also a benefit of running e45 is you only have to bring half the amount of e85 to the track. then mix e85 and 93(e10) half and half and you get roughly e45.

True but
If you are talking about NA ...... the issue then is any power gains from E85 are halved.

but according to the screenshot chart you posted, not much gain after 40% eth

anyone looked into how much premix lower the octane level?

By 'gain' they mean in octane rating. The gain in power in a turbocharged engine is directly as a result of improved octane (mostly) which allows higher boost. In an NA we are not knock limited so no gains there but can still get gains from being able to pack more energy per gram of air into the combustion chamber. By reducing ethanol content by half you reduce that gain by half.

I swear you don’t have a lick of sense to just let it go. Just the same, I’m retracting my previous response.

There’s a lot you’re missing on this topic. As far as I can tell you never actually ran or even long term tested full E85. There’s more to it than octane, and certainly more to it than you’re aware of. That E-percentage testing data is very old. And it wasn’t conducted on a turbo rotary engine. And you certainly aren’t the source behind it, or have ever fully tested it yourself fully on a rotary engine. It’s just the usual 1 + 1 = 3 methodology.
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You either didn't read or just plain don't understand the point I made above about what is relevant for a street driven Renesis turbo. But that doesn't surprise me given that you think you know everything about everything ... it's easy to miss the point.

Also ... Congrats on finally figuring out how to use the quote button ...well done!