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Saw the instagram post from latest dyno session. What was the main issue ?
To be honest it's just a really steep learning curve tuning a rotary on methanol, especially with no baseline methanol tune to work from.
It's very different from E85/E0 behavior. For instance at a 2500rpm idle, it likes somewhere in the neighborhood of .76 to .70 lambda, when it runs any leaner than that the motor's response is immediately audible and EGT's jump really quick, you also run the risk of there not being enough premix in there so it HAS to idle much richer than when on E85. But then if you run just a little too rich at any point during a pull then the plugs immediately foul and you don't really get any early indication from the EGT's to abort before that happens.
We're most likely going straight to the FuelTech FTSPARK CDI and a wideband controller and O2 sensor that can read well past the low .5's before the next session.
Once those are in place it just needs more time on the dyno.
It easily did 150mph at 6500rpm in 3rd. 3rd is geared for 196mph at 8500rpm.
We'll get there.
it said from 4 days ago, so my assumption was some of the info was edited or updated:
landspeedrx8We’re ready to finish the E85 tune and move on to the final methanol tune soon!
Dyno summary:
-E85 without an intercooler
-2.73 rear gear (need the nitrous to get the revs up/turbo spooled)
-TPS was faulty, had to modulate the throttle before we had to call it quits.
-Mustang Dyno results:
554rwhp (~637fwhp)
400tq
7400rpm
28psi
Post-Dyno:
-Compression check was great and has been slightly increasing.
-Oil & filter were free of any bearing material and fuel dilution was typical.
-Catch-can oil volume was typical .
-Spark plugs were excellent even with 3:1 premix and 600mj spark energy.
-TPS sensor replaced.
-Plug wire terminals replaced
Next Dyno:
The @nitrousexpress Shark SHO single nozzle system will supply an add’l 50hp from 3.5K to 6K rpm to help bring the revs up and spool the turbo. We’ll also increase the rev limiter to 9K RPM.
It should make 700rwhp at ~40psi & 9K RPM but that’s above and beyond what we need for 200mph.
it said from 4 days ago, so my assumption was some of the info was edited or updated:
That post was just more of a thorough recap.
Going into the next dyno:
-TPS has been replaced.
-Added fuel temp sensor to allow fuel calculation to compensate for fuel density.
-Andy has provided his recommendations to resolve the injector staging issues. Currently there are 4 stages: Stage1: 2x 2450cc, Stage2: 2x 2450cc, Stage3: 2x 2450cc, Stage4: 2x 2450cc (should address the rough transition to Stage 2 from 6K on up)
-Nitrous will activate at approx 3.5K/0psi to 6K/12psi
-Switching back to methanol now that we’re approaching 40+psi without an IC.
-Pulls will be made to 9K
-Once everything checks out we’ll perform 1st through 3rd gear pulls to see if we can max out the dyno at 190MPH
With the current 5-speed sequential gear ratios and 2.73 final drive these are the potential maximum mph per gear;
Forgot to mention that 8700 RPM will be the approx sweet spot for gear changes as the RPM drop lands perfectly within the ("useless" ) power band of 6K to 9K. I'll also complete the pass at the top of 3rd gear for the Phase 1 goal of 200mph.
because; and I had agreed with it some in the past but now see it from an entirely different angle; in that it’s actually a turbo choice limitation rather than the Renesis engine.
since you base everything on experience, then with you not having experienced using a bigger turbo is holding you back from seeing it. Rather, imo the issue is choosing a turbo running that far out on the compressor map, it’s the ever decreasing compressor efficiency that results in the limitation you’ve noted and theorized on. It’s why I proposed the lower rpm limit on my own smaller turbo project, as well as encouraged others here with larger turbos to pursue pushing more. So my belief is that the limits are spool vs high rpm power, and the choices made for one or the other.
So given this turbo against the intended goal, I’m doubting that there will be an issue for that specific reason. There may be an issue, but I’m thinking it will be for something else, if at all.
.
So I’ll just go ahead and spill it; imo the biggest issue with the siamese port is that it’s not actually sealed separate between the two rotors. To do that with the standard width center iron would have made the center discharge ports even smaller. Mazda did a good job trying to keep them two sides as separate as possible, but it’s not entirely possible with a single sleeve like that. It may not seem apparent why that’s an issue, particularly wrt backpressure. There’s more to it than having the divider plate to prevent blowing superheat exhaust gasses at the opposing rotor/side seal.
The number may be wrong but the theory behind it is still relative and will play a part in this build.
Originally Posted by Brettus
I'll be forced to agree with you if this system can rev to 9000 and make the sort of power talked about above. Pretty sure it wont ... bring it on
I'm disappointed Brett.
Back to back to back comments with nothing technical, logical or even remotely intelligent to contribute.
You've definitely taken a turn for the worse by choosing a cynical response to your "theory" being proved wrong.
I'm not here to appease you or prove you wrong ("again"). I'm here to share information and engage in technical, yet "intelligent", conversation for the sake of forward progress.
You lose whatever credibility or respect you have left on this forum (or worse, in the rotary community) when the best you can do is post ominous and unsupported comments like these that do nothing more than provoke unnecessary hostility.
People can't take you seriously when you carry yourself like a salty "punk" or worse...a "hater".
Not exactly the ideal reputation...
(And based on your historical tendency to be a master of deflection, I expect we'll see you stick with that tactic here shortly...)
Sorry you feel that way. Let's try keep replies to the point without taking swipes at each other ..... I already get enough of that with Team. Those posts do reflect my current beliefs, however they were not meant to discredit what you have done. You made more power than anyone ever has which is no mean feat and I congratulate you and your team for that.
As far as not posting anything technical ... I already did that and didn't want to repeat myself, but seeing as you mentioned it :
The theory I came up with was based around using turbos that most would consider appropriate for a street driven or even a race car. What you did was go several steps bigger than that and your (current) nice peak with an unusable powerband is where you are at right now.
If I'm honest , I never considered doing what you have done , and even if I had I probably wouldn't have expected you to achieve what you did. So yeah , you proved me wrong.
But if I analyse what you achieved the key point for me is that by using such a monster turbo , you reduced EMAP to a level below the point where, in the past, I've personally started having issues. For me the deadly combo has always been high backpressure (over 26psi) combined with elevated rpm (over about 7700). My theory for why this occurs this are covered in my '450' thread.
So this is why I think your 9000rpm power goals won't work out as you believe.
The problem with the center port is that it's inefficient and holds a lot of heat. If you're increasing port volume as much as you would be with the peripheral ports, why keep them?
Originally Posted by Brettus
Was looking at doing the peri exhaust idea a few months back . If I did it I would definitely shut off the Siamese port for the reason reddozen gave .................................. plus a few other reasons.
Sorry you feel that way. Let's try keep replies to the point without taking swipes at each other ..... I already get enough of that with Team. Those posts do reflect my current beliefs, however they were not meant to discredit what you have done. You made more power than anyone ever has which is no mean feat and I congratulate you and your team for that.
As far as not posting anything technical ... I already did that and didn't want to repeat myself, but seeing as you mentioned it :
The theory I came up with was based around using turbos that most would consider appropriate for a street driven or even a race car. What you did was go several steps bigger than that and your (current) nice peak with an unusable powerband is where you are at right now.
If I'm honest , I never considered doing what you have done , and even if I had I probably wouldn't have expected you to achieve what you did. So yeah , you proved me wrong.
But if I analyse what you achieved the key point for me is that by using such a monster turbo , you reduced EMAP to a level below the point where, in the past, I've personally started having issues. For me the deadly combo has always been high backpressure (over 26psi) combined with elevated rpm (over about 7700). My theory for why this occurs this are covered in my '450' thread.
So this is why I think your 9000rpm power goals won't work out as you believe.
Glad to see a down to earth response from you Brett. I can appreciate and respect this.
I forgot I had this...Team is right, it's your hot-side that's the issue (or maybe the fact that you're running a full-exhaust? are you?), not a motor port flow issue. I'll post an emap/imap log from the GTX5533R Gen2 pulls, that one shows even better imap/emap ratio results and goes to 26+psi I think but I only have a pull to about 8250rpm. emap actually starts dropping well below 1:1 as imap holds steady and rpm climbs. The motor flows bro...
Plenty of my own theories have been blown out of the water, probably as much or more by myself as anyone else. This forum is a testimony of that and I neither take it personally nor feel any shamed over it, due to having no desire to be worshipped as the king of the forum hill.
What we’re talking about now ties in to what I’ve been trying to explain about what makes the Renesis different than the prior 13B. Those details matter. It’s more than the hot side though. The cold side matters too.
that said, the comment wrt the siamese port theory is taken out of context. However, it will be addressed at the appropriate time and place.
And as promised, here's an imap/emap trace from one of the GTX5533R Gen2 pulls made to 27psi at 8111rpm. emap is actually decreasing as rpm climbs and the imap/emap ratio of 1 to .71 speaks for itself.
Pretty amazing what the motor is capable of, especially at higher rpm and with a turbo that can flow.
And as promised, here's an imap/emap trace from one of the GTX5533R Gen2 pulls made to 27psi at 8111rpm. emap is actually decreasing as rpm climbs and the imap/emap ratio of 1 to .71 speaks for itself. Pretty amazing what the motor is capable of, especially at higher rpm and with a turbo that can flow.
If power is also increasing then yes, I agree. Is it though ?
08-27-2020, 02:04 PM
) power band of 6K to 9K. I'll also complete the pass at the top of 3rd gear for the Phase 1 goal of 200mph. 
