Owens Racing

iTrader: (7)

I am running a snow progressive controller. I did many logs and from those I converted the original afr and map numbers, did the math to get my desired 12:1 and this is what I came up with. tried a little smoothing.

Does the lean spot in the upper RPM's and load cells seem correct? I assumed it might be being the meth controller references the Mass Air too. This could be where the pump is at full song.

Thanks in advance.

Owens

tephra

iTrader: (6)

forget the math..

start with a richish tune, then lean it out slowly until you get your desired afr..

tephra

iTrader: (6)

ps it looks like you have lean spool enabled still? might want to turn that off to make life easier..

Evoryder

iTrader: (55)

1. how much meth you spraying
2. what are your mods
3. how much boost
4. what is your activation point for boost
5. tephra is right about lean spool and meth
6.definitely start rich and work down like teph said.
7. i hope you have a fail safe

Owens Racing

iTrader: (7)

have a fail safe and I plan to be close 12.5:1 when tune is finished.

I was looking into the lean spool.

So basically scratch this tune go back to me pump tune and log with lean spool off?

Is there a need to start over after lean spool is disabled? I do my logs in third. I was understanding lean spool effect fourth gear.....

Thanks
Owens

Owens Racing

iTrader: (7)

boost spiking 28 settling to 24 at <7500

Evoryder

iTrader: (55)

Lean spool disable will make the tune richer and more consistent. 3rd, 4th will typically be with .2-3 a/f of each other 5th will be richer than both as usual.

Tuning:

a) Logging

Suggest tuning 3rd from 2500-7200rpm, 3rd 3500-7200rpm, and other variations higher. You wanna hit as many daily driving scenarios to get consistent load cells to tune. I would also log in 4th from 3000/3500-7200rpm(if you have room to see what load cells you hit up top)

b) Timing/Fuel
Start with low timing and see if your car takes to tuning with more timing less fuel or less timing more fuel. My car hates advanced timing, and will respond very well to very lean a/f and little timing.

c)

Meth/Water:
Try not to have too large of a nozle and also have the meth come on too early. Will cause knock if too much is sprayed before boost or during spool.

d)

2byte load:
I hope you have this enable in your logger. Makes for much accurate tuning.

If you have more questions or need further elaboration feel free to ask

Owens Racing

iTrader: (7)

Def running 2byte. As well the tune that was(still on it actually) in previous is an excellent pump 22 psi tune. So I had a good base to work with.

I will do the lean spool and log it. As of now I truly after WOT dial in. I am going to the track this weekend. 12.3@111 on pump tune. Hoping to get in the 11's once it is dialed in.


As well any chance the cars liking fuel and liking timing difference being relative to the quality of the air that each have in their different climates?


As well is the lean spot up top in the map I posted, def. from the methanol injection?

Evoryder

iTrader: (55)

Timing and fuel diff is based on different variables. Climate, maf sensor, knock resistance, etc. Each car can handle a different load and can make different power levels also even with the same mods.

Lean spot is definitely from the meth...you have to pull more fuel at certain load points where the meth hits.

Owens Racing

iTrader: (7)

Climate is Air, Your Mass Air is measuring Air Density relative to climate. Knock resistance is relative to Air quality hence IC makes for cooler Air.

So guess that might be part of why some "cars" like fuel and some like timing.


Thanks for the confirmation. I disabled the lean spool and plan to give this fuel map a go.

Thanks again,
Owen

Mr. Evo IX

iTrader: (5)

Owens, have you considered tuning it lambda instead of AFR? This will give accurate o2 readings with mixed fuel. eg remove the calc for gasoline from your equation. .81- .82 lambda is equal to 12:1 AFR.

Owens Racing

iTrader: (7)

I actually have considered it. The problem is one of my friends that I resource on tuning, has never mentioned lambda. I really need to sit down with him and discuss it. Maybe he uses and assumes I do not know about it. IDK. As well people have tuned with great success using AFR. So with that being the norm for most, well it seems to be. I pretty much have stuck to it.

What confuses me is why use LAMBDA when it has its equal in AFR. Basically a=1 and 1=a what does it matter.

Mr. Evo IX

iTrader: (5)

14.7 AFR = stoich for gasoline - but not stoich for a meth gasoline mixture. Some wideband's do a calculation to provide a reading in AFR for gasoline, That computation is not calibrated for other fuel types. The computation is lambda * 14.7 for gasoline. You can figure lambda by (AFR / 14.7) = lambda.

For methanol, stoich is about 6.3 AFR. Adding, 50% methanol to gas creates a new stoich AFR value as it's neither gasoline nor meth but it will still be 1.0 lambda.

TouringBubble

iTrader: (2)

Most people are just used to tuning for gasoline AFR and leave the calculation in there ... if you know the AFR target for gasoline, it will be the same for any other fuel if you leave the gasoline calculation.

So, if you know that you would want 12.5:1 on gasoline, you can run any fuel to 12.5:1 with the gasoline multiplier and you'll still end up at the correct lambda value for the new fuel. The AFR won't be correct though as 12.5:1 on gasoline might actually be 9.2:1 on Ethanol blend.

Personally, I'd just use lambda, but the calculation doesn't really matter.

Owens Racing

iTrader: (7)

The AFR's before:




The AFR's now:




Still got more work to do, seems to be on the right track.