Take a look at my log, 50trim 23psi on meth

[Killa_dsm]

It looks like you're on the right track to be getting your timing back that well from only a few % in a few areas! What are you running now for meth mixture? I was running blue juice (which i found out today that what i had been running was only 30% meth 70% water) I dumped 2 bottle of heat into the 2qt tank when there was only a 1/4th of a tank of blue juice in there and as soon as the higher meth mix worked it's way through my knock went completely away.

41lbs/min looks rather nice too, that's a good bit of air!

I was running blue smirf piss, I think the 50/50 mix and the color dye. But I decided to run straight meth to see how it would affect my tune. So I put in 3 bottles HEET and thats the log you see.

41lbs/min is not significant, unless your 2g head is stock and stock intake/throttle body. Meth injection is like racegas. Turn the boost up. 23psi on a fifty trim is low for a pump/meth tune.

Yeah, I plan to run more boost but I wanted to get my timing back up to where it was suppose to be. And yes I have stock head/intake mani and throttle body. So how many lbs a min should I be seeing? I hope to get it tuned to about 24~25psi on pump gas and meth. We will see how that works out.

 

[Killa_dsm]

Well tonight I decided to go out and up the boost and tune a little more. I got it up to 25psi without any knock by adding a couple more % on my AFC with 16* of timing up top! If I remember right I was flowing about 45lb/min. Does that sound right for 25psi? I also need to upgrade my Greddy Type-S since it seems to flutter under high boost and not stay shut.

Over all I am very happy with my meth kit. At first I wasn't too happy with my results but with a little tuning and experimenting with different mix's, I am very happy with the results!

 

[2gGSX]

Just a little clarification in regards to the g/rev calculation (and airflow in general for that matter). You have to factor in any adjustments made by the SAFC to determine true airflow and true g/rev. If the SAFC is zero'd out and the chip is doing all the compensation (again assuming the chip is set correctly, and base fuel pressure hasn't changed), then all airflow readings and the normal g/rev calculation is fine.

In that second log where 5000 and up you added +2% however, the situation changes. At 6000 RPM you floweed 41.62 lbs/min as read by your ECU/logger. That's after the SAFC added 2% airflow though, so you have to divide by 1.02 to get true airflow--40.80 lbs/min. After that, you can do the g/rev calculation like normal.

Also, your front O2 value of .96/.97V stipulates that you're actually running very very rich, like near the factory rich (9.5:1). It does seem to get rid of your knock though.

 

[Killa_dsm]

Just a little clarification in regards to the g/rev calculation (and airflow in general for that matter). You have to factor in any adjustments made by the SAFC to determine true airflow and true g/rev. If the SAFC is zero'd out and the chip is doing all the compensation (again assuming the chip is set correctly, and base fuel pressure hasn't changed), then all airflow readings and the normal g/rev calculation is fine.

In that second log where 5000 and up you added +2% however, the situation changes. At 6000 RPM you floweed 41.62 lbs/min as read by your ECU/logger. That's after the SAFC added 2% airflow though, so you have to divide by 1.02 to get true airflow--40.80 lbs/min. After that, you can do the g/rev calculation like normal.

Also, your front O2 value of .96/.97V stipulates that you're actually running very very rich, like near the factory rich (9.5:1). It does seem to get rid of your knock though.

Yes, I found that out about the g/rev and calculating the SAFC out from doing a little research and reading Nathan's (spyderturbo007) post on a different thread.

And I also noticed that with my o2 values as well. It does seem high but the knock seems to go away so I guess it works. Do you think its find if I run those o2 values?

Thanks!

 

[2gGSX]

It could just be that your specific situation requires you to run that rich in order to avoid knock. So yes, keep it as it is as long as it doesn't knock.

 

[turboglenn]

While 2gGSX has a point, dont' forget that too much fuel can cause kncok too. If i tune my car anywhere in the 10's it's getting knock. I have to run mid 11's for it to really burn smooth and have no detonation from the extra unburnt fuel.

Try that if richening it up doesn't work, it helped me!

As for Black95tsiawd saying 41 lbs/min is not signifigant, shouldn't that be the same as the airflow from teh trubo and calculate out to equall some where between 340 adn 390 horse depending on the tune and maybe even 400 with a really good tune. good enough for me on a dd car.

 

[2gGSX]

While I agree that that is really rich (even more so with the 12 GPH, or 757 cc/min M12 nozzle spewing more fuel in), it seems to get rid of knock, which is always my first priority.

In my opinion you're just at the limits of your fuel, meth and all. Even after the meth injection, I'd put you between 92-94 octane.

Highlight this if you really want to see the fuzzy logic calculations
Assuming you *are* at 9.5:1, you'd be running about 4.63 lbs/min of fuel total. The 50/50 meth being injected gives ~380 cc/min, or .659 lbs/min of meth. Your effective octane rating would be 113*(.659*6.4/14.7[to factor in the lower energy content of methanol]/4.63)+91*(1-.659*6.4/14.7/4.63) = 92.36. That's not 100% accurate, but I'd put you right around there (within 1 or 2 points at most).

If you were to lean your AFR out, you'd have to either lower timing or drop boost. At this point, your only option would be to lower boost and thus some airflow. Your best way of figuring out which nets you more power would be on a dyno, although something like a 70-90 mph 3rd gear pull time comparison may work as well.

I'm actually just ranting now.

 

[turboglenn]

While I agree that that is really rich (even more so with the 12 GPH, or 757 cc/min M12 nozzle spewing more fuel in), it seems to get rid of knock, which is always my first priority.

Fuzzy math warning: this probably isn't accurate but it's probably a good estimation
In my opinion you're just at the limits of your fuel, meth and all. Assuming you *are* at 9.5:1, you'd be running about 4.63 lbs/min of fuel total. The 50/50 meth being injected gives ~380 cc/min, or .659 lbs/min of meth. Your effective octane rating would be 113*(.659*6.4/14.7[to factor in the lower energy content of methanol]/4.63)+91*(1-.659*6.4/14.7/4.63) = 92.36. That's not 100% accurate, but I'd put you right around there (within 1 or 2 points at most).


If you were to lean your AFR out, you'd have to either lower timing or drop boost. At this point, your only option would be to lower boost and thus some airflow. Your best way of figuring out which nets you more power would be on a dyno, although something like a 70-90 mph 3rd gear pull time comparison may work as well.

I'm actually just ranting now.

With a 70/30 blue juice fluid on an M7 nozzle coming on at 10psi, i was getting knock on my runs and was seeing afr's in the 10's and 9's... ON advice i found through HOURS of searching this forum i started leaning it out while on the meth. After sdjusting the afr after a few pulls I was at 12.2:1 WOT with ZERO knock at 16 psi locked timing. I had also added 2 bottle of heat to a 1/4th tank of blue jusice in a 2qt tank int he back) making what i guess to be 80/20 to 85-15 meth to water

Well, on 80% meth and 20% water i was still only at 20 PSI, and locked 16* timing but i went to an M10 nozzle and i was still at 12.2:1 at all RPM's at WOT, again with not the slightest bit of detonation and my sensor is set rather picky. Not only was i was not knocking or even showing the slightest signs of pinging, i was gaingin a LOT of power, it's the fact that it hooked up in third at 4500 RPM when the turbo hit hard and spun for a second and then then hooked up is when i think it detroyed the tranny. It was holding me in the seat a lot harder than befrore at more than 20psi (except for the time i tuned the 468HP race gas tune that i ran for a month on the streets with slicks after i got it tuned on my old motor) THEN i had to give teh extra injectors and controller back and order my own injectors. Sorry to ramble, i butted heads with the woman earlier and a 5th of vodka was my only savior at the time, so im fairly buzzed !

EDIT that highlight to see thing you did is cool as hell 2gGSX , i read it all, makes great sense

 

[Killa_dsm]

Wow thanks for the help guys. And Tom, those highlight calculations make me feel like I know nothing about dsm's! Thanks for all the great info.

And turboglenn how much airflow were you pushing to get 332whp?

 

[2gGSX]

Those numbers are all bs I tell you, I make stuff up as I go along!

330 whp should be about 33-38 lbs/min based on tuning/setup/etc.

 

[Black95TSIawd]

As for Black95tsiawd saying 41 lbs/min is not signifigant, shouldn't that be the same as the airflow from teh trubo and calculate out to equall some where between 340 adn 390 horse depending on the tune and maybe even 400 with a really good tune. good enough for me on a dd car.

When I said 41lbs/min is not significant, I wasn't saying its not good, I just meant it more for his setup. He should get more out of it, and he did! Which is great. The 2g stock head mated to the stock 2g intake manifold is choking airflow big time. He is now at 45lbs/min which is awesome.

For comparison sake, I went 12.1 and a best trap speed of 112 with just 39lbs/min.

 

[Killa_dsm]

When I said 41lbs/min is not significant, I wasn't saying its not good, I just meant it more for his setup. He should get more out of it, and he did! Which is great. The 2g stock head mated to the stock 2g intake manifold is choking airflow big time. He is now at 45lbs/min which is awesome.

For comparison sake, I went 12.1 and a best trap speed of 112 with just 39lbs/min.

Oh ok I see. Well its more like 43lbs/min instead of 45lbs/min because I had to add a little more fuel up top on my SAFC.

And nice 12.1 with 39lbs/min! Wish I wasn't fwd