Target AFR chart discussion
 

Gents,

Looks like a few of us are using the Elite series now which is great to see.

I thought it might be interesting to compare / see what others are doing in regards to the target ARF charts.

I'd love to see what this look like from Pump vs E85. but to keep the conversation simple would like to see what your AFR chart looks like for PUMP for now.

I know we will all have something different maps but would be useful comparing. (as even just collecting some, I've noticed different approaches) and I know pump fuel in the US is better than what we get in AUD. but this is just a conversation starter.

Really I want to learn more and I'm sure there are others in the same boat.



So to start is off this is the Stock Haltech FD single turbo map.
https://cimg3.ibsrv.net/gimg/www.rx7...0a7fa8da73.jpg

Haltech base map


These Next 2 are from the haltech tech video just screen shots from Tuning Fork. what I find interesting it their significantly richer than the base map haltech issues

https://cimg4.ibsrv.net/gimg/www.rx7...70d6c7f077.jpg

Haltech youtube how to tune a rotary - Tuning Folk video 1

This is then a different map they show in the same video

https://cimg5.ibsrv.net/gimg/www.rx7...a2897a6f3d.jpg

Haltech youtube how to tune a rotary - Tuning Folk video 2



Im guessing the base map was designed for Fuel economy where most of us are here for performance and power?

Comments?

Arghx. don't know if you will see this, but I found your other thread really useful and I wanted to compare maps

this is the conservative map converted to the others.

Doesn't look that conservative really. But as noted in the thread it came from
https://www.rx7club.com/rtek-forum-1...tables-890528/
Its designed for the FD with a Catalytic converter still

https://cimg3.ibsrv.net/gimg/www.rx7...65c2a7bf90.jpg

A 13.0 AFR Idle? They're going for some chop with a huge streetport? :P

Sorry, Havoc, my last final is this morning, then I can start digging into this with you. Definitely the #1 thread on my mind right now being that I know what values SHOULD be for a reciprocating engine, and why, but on a rotary, it's something that takes experience and will vary greatly from each motor due to porting, injection setup, etc.

Heres a copy of my target table for the FD.

Keep in mind my car idles between 1500-2000rpm and very rarely gets below 1500rpm. My target AFR table is a little richer for the semi pport as it has some difficult characteristics with the ProJay intake setup if it's much leaner than this. I typically prefer to go very lean in cruising (15.5-16.5) but the single blade throttle doesn't take kindly to that lean of a mixture.

https://cimg9.ibsrv.net/gimg/www.rx7...29f3f1eb7d.png

I think that we should include vehicle setup and fuel content for each of these posts.

S5 13bt - Mild Streetport
Borg Warner EFR 9174 w/ 1.00 A/R IWG
IGN-1A Coils
e85 Flex Fuel and 91 Octane e10 California Crap Gas
etc etc

I haven't decided which one to use as a BASE yet, then modify fueling for ethanol content/fuel temperature via Flex Fuel Sensor.

So here's how I'm addressing Flex Fuel:

1) Enable the 3rd Axis (aka Fuel Composition)
2) Set Values of Ethanol Content: 0% (some states don't have E10 Pump Gas), 10% (California Pump Gas), 25%, 40%, 55%, 70%, 85% (E85, duh), and 100%.
3) Extrapolate AFR Tables Based on Greg Banish's Books and Lambda Values for Ethanol Content
4) Remember that e85 prefers a LEANER standardized AFR to run properly when comparing accepted stoichiometric values. ex. 9.85:1 Stoichiometric Value for e85. However, running a 10.5:1 AFR for 300kPa on Pump Gas E10 would be 10.5/14.75 = 0.712 (Lambda).

0.712 x 9.85 = 7.01 AFR at 300kPa for e85.

HOWEVER, we know that this fuel in particular likes to be run leaner, so maybe closer to 7.7 AFR at 300kPa is more reasonable. I'm going to put in here that it's about +0.5 Lambda Leaner than pump gas throughout the entire table.

Anyways, here's an unpolished, quick and dirty base-target value. I'll go over this with a calculator later.

Thanks Fella's.

Copeland Im running a single 90mm TB (DBW) and I can get mine to idle at 1000 rpm no probs. I struggled to do that with my old setup (the stock cosmo TB)

But I know with your Semi PP tat will be the driver.


SLA:

yeah Im running the same 4D for fuel correction. I spoke to a few people and they all said the same thing that don't go overboard with the correct. I'm planning to do 0 - 25 - 50 - 75 - 100.

In saying that keen to see how yours looks :)

I spent the day tuning my daily driver Integra with Hondata S300, so what I roughed up on Haltech is attached above. I'll go through the rest of it with real-world numbers, then attempt to do the fuel tables. Now I'm totally understanding why Skeese is doing ms/fuel value and learning to tune without VE. It's hard to estimate these arbitrary VE numbers, but knowing the fuel calculations I could draw up a ms/fuel value pretty fucking quick and build a set of trends to how I want drivability to be.

As with the 4D Slider, I'm happy with how I have mine setup. I don't want it to jump from 75% to 100% when running e85. If I put in e100, e85, e70, e10 (pump gas), e0 (out of state gas), or whatever blend of ethanol content when traveling/roadtripping, mine is dialed.

SLA, dont know if you're going to use the LTFT. But just to note you only get 4 cells in 3d mapping of the LTFT. Would be nice if it was 8 like you need.

Right, so I'd expect to use 10%, 40%, 70%, and 85%. That would be the most common (10 and 85%), then 70% (the lowest e85 can be, legally), then 40% to interpolate between the pump gas and e85.

Another approach would be 10%, 25%, 40%, and 85%. Ethanol content drops incredibly quickly with small quantities of pump gas, so this would be the most used percentages and hopefully the ECU would be able to interpret between 40% and 85% without a problem.

Either way, LTFT shouldn't be changing shit without me entering the ECU via laptop and saving those measured cells.

LTFT offset is continuously active. Not just when you save the table to the base VE table. So, if you're going to employ the feature, set it up properly.

Good thread.

How come you guys use a 4D table for fuel composition as opposed to enabling a Fuel Composition Correction Table?

Anyway, here is my map. Think I may be way conservative compared to you guys.

Mods are:
Stock ports
T04S 0.82 tuned for 90kPa max boost
V-mount (intake temps tend to be around 40-50 degrees on track)
Tuned for track with a tiny bit of street driving

Attachment 751479

Also run a gear based correction table, which targets a higher AFR at high rpm in gears 4 and 5. I am thinking about changing the Y-axis here to be based on MAP instead of rpm (so it doesn't richen up on lift off).

Attachment 751480

Randomly carousing through a thread and found me.

I'll post my target AFR map tomorrow. I'm in the middle of a weird tuning process on a haltech PS1000 that involves a semi motor, completely open dump exhaust, bigass turbo, E85, and staging a lot of big injectors on top of big injectors. I want to go elite, and can afford to do so, but want to understand what's really going on behind the fueling curtain that VE hides an this is the perfect learn-all insano motor.

The semi does consume a bunch of fuel, but I've gotten it to brap and chop hard at a 13.5, just not as low as I want yet. I'd imagine Cope's may need to idle a little bit richer due to the projay, but ultimate badassness does come at a price. And his shit IS badass.

I feel like target AFR maps really depend on the purpose and use of the car. If you are a streetcar running mid to high boost for occasional spurts here and there then having a target AFR map that riches progressively with boost and rpm in a smooth and linear fashion is great.

BUT

If you are tuning something you are going be running 30+ PSI into and beating on it like hell constantly at 600hp+, you should brick the target AFR a bit and make it hit and stay. A tune that actually hits and holds a solid AFR is a lot safer than one that chases a moving target semi accurately.

Skeese

Jarik,

I think with our pump fuel been a little bit shitter than the US guys I think its a safer option.

4D for the LTFT just seems the better way to do it and more control. (it still used the Composition correction table anyway)

"A2W Intercooler" in your signature :egrin::icon_tup:

Just saw this. Looks straightforward enough to me. Is there a particular question you had? That was designed as a safe starting point for a broad variety of setups.

Jarek, regarding "I am thinking about changing the Y-axis here to be based on MAP instead of rpm". Did you every try that and if so did you find a usable solution?