Tuning Meth.. Same AFR with and w/o meth, reg. 93 fuel map!

After installing labonte MAF based meth kit, tried to run it with the same map (no changes for meth were made) , just to see how it gets lean.. Surpraisingly, gar did not get leaner!

Exactly the same situation as described here:

http://www.romraider.com/forum/topic4493.html?hilit=meth%20lean

 

I've attached the log, just in case anyone want to see it.

meth trigger point is 3v (+/- 0.2).. I do have a flow gauge, so I am sure it was injecting 200-300 ml/min at least.. (bad i can't datalog it)

 

Not sure what I am asking here :-), but may be there are members had the same experience.

Anyway, now i am going to load a new map, leaner and more timing added. will se how it goes.

meth.csv

Please enlighten me a little bit.

 

Why would you expect the meth to casue a richer mixture? Looking at it from the outside (I have zero meth tuning understanding) I would assume that the meth being introduced post maf would cause the air to cool and become more dense, therefor you would be packing more oxigen into the cylinder than what the Maf sensor saw initially. All of this would (in my mind) cause a lean condition..no?

oops..I think I misread your initial post..the person on Romraider expected it to get more rich, you expected it to get leaner but in reality, nothing changed?

^exactly.. Expected to go rich, but it was not.

BTW, I've run meth map , will post logs in 10 min. More timing and less fuel...

Ok, here the couple of runs:

 

13,5 AFR at 5K RPM WOT.. is this OK? Too lean? No knock, EGT is low.. I assume it's OK, please correct me if I am wrong.

Now I am going to add more timing..

meth1.csv

That sounds REALLY lean to me..

 

Without meth I target about 11.2-11.3 on the high load high RM range.

Yeah, I've added fuel there. The strange thing: if LC-1 reqads correctly, 13.5.. Why stock O2 sensor rerads 11.2? i know it cna't read richer than 11.2, but 13.5..?

may be my LC-1 is giving me wrong numbers? i will re-calibrate it, but still at idle it reads quite normal.

Just saw this over at RR, looks like you should target low 12's..

 

http://www.romraider.com/forum/topic4306.html

Yeah, I've added fuel there. The strange thing: if LC-1 reqads correctly, 13.5.. Why stock O2 sensor rerads 11.2? i know it cna't read richer than 11.2, but 13.5..?

may be my LC-1 is giving me wrong numbers? i will re-calibrate it, but still at idle it reads quite normal.

 

Keep in mind that the stock 02 us pretty useless once you you go into boost.

 

a quick and easy way to check your WB02 is to log the front 02 and the WB02 while in close loop...the numbers should be close.

Meth should richen things up by a noticeable amount unless you're not injecting enough. I've done baseline pulls on my car with and without meth (no other changes made), and my Perrin unit drop my AFR's by half a point (11.5 to 11.0).

 

As for 13.5, it sounds really lean to me. I run 12-12.5 with my set-up and most think I'm a little on the aggressive side. I've never checked my EGTs, but my timing is strong and I have no knock. It really sounds like you wideband may be off. At an AFR of 13, my LC-1 and stock sensor would read somewhat close to each other. At stoich they were pretty much bang on.

 

What are you injecting? 50/50 mix of water and methanol, wiper fluid?

Spec B, in CL WB02 and stock are close..

 

What are you injecting? 50/50 mix of water and methanol, wiper fluid?

 

its a crazy mix; 40% isopropyl alcohol (rubbing) + 60% washer fluid (30/70).. so, it would be something like 40% isopropyl, 20% methanol 40% water.

I'd plan to use isopropyl, if nobody will tell me any bad of it.

 

I also think that my LC-1 may be off. Damn LC-1 if this is true. Will re-calibrate it when I get back home.

BTW, I've added more timing, like +5 for hi-load area.. got some knock around 4-5K rmp.. (no logs with me)

BTW, if max WI flow at like 5500 RPM, instead of redline, will it help to supress knock?

Speaking of AFR: I've seen people have from 13.5 to 14.7 on hiload area on OP maps.. How much they could inject to get real afr around 11.5? I have 12.5 on the same areas, and getting 12.5 real (if LC-1 correct, obviously), AFR with meth, when

I should be much richier!

Damn lc-1 !!!

Final results? Was curious too if meth, with no change in tune, shows up on the wideband O2 sensor.

I am going to post my logs soon.

It was a problem with my MAF scalling, when i fixed it, my AFR with and without meth showes correct values.

Now I am running 12.5 AFR average with meth at WOT, about 5-6 degrees more timing, and have no knock at WOT at all.

The only thing I do not like is that my AFR is fluctuating sometime on up to 0.4 points, going leaner or reacher. My guess this this is not really linear METH injection, depending from weater and temp. Bul like I said, it does not cause knock, so i am happy.

Will be installing TMIC soon, will post soem logs.

So, here is the result. With my new custom made TMIC (for $200 total), with 50/50 alcy injection I am getting this.

Real load number are higher, my MAF is tweaked to lean AFR down to 12.5, in real I was getting about 3.5g/sec.

This run was made in about 75F outside.

 

UPD: Second log-> 4500-redline

romraiderlog_20090615_091931.csv

romraiderlog_20090615_092819.csv

What is your map afr target? Is it 12.5?

What is your map afr target? Is it 12.5?

 

14.7-13.9 in most OL areas.. Remember, I run METH - it makes BIG difference

The whole meth thing confuses me..a load of 3.5 g/rev sounds like some serious power. I hit 3.3-3.4 in the dead of winter...3.1 now.

I have seen 3.5 g/rev when scaliong OL MAF for my intake mod. may be it was because I had too high values for MAF that time.. Not sure. You can have crazy load values just by changing your maf scaling. more numbers there for given MAFv = more load.

Load doesn't matter one bit if your MAF isn't scaled properly. MAF volts is a better gauge of power made or air being moved.

^Agree 100%. As for a MAFv, the max I am getting is 4.35v in a summer, which is relativelly low number.

As for a MAFv, the max I am getting is 4.35v in a summer, which is relativelly low number.

 

Low because more than likely it is larger diameter, essentially, than stock which would require less voltage to pull the same amount load and/or g/sec; which goes hand in hand with why you had to spend so much time on your scaling with the intake.

 

So even the MAFv value isn't apples to apples when using non-stock intakes as far judging power from MAFv.

Low because more than likely it is larger diameter, essentially, than stock which would require less voltage to pull the same amount load and/or g/sec; which goes hand in hand with why you had to spend so much time on your scaling with the intake.

 

So even the MAFv value isn't apples to apples when using non-stock intakes as far judging power from MAFv.

Nothing is really apples to apples, there is even variance on the stock intake. I was refering to gauging power on the same vehicle.

I was refering to gauging power on the same vehicle.

 

I understood what you were getting at, I just didn't want others to read is as MAFv was absolute.