[Jeff@TopGearSolutions]

Spraying a smaller M5 nozzle might benefit for heat soak otherwise the only benefit would be to increase ignition and maybe more top end boost. But you know this already.

[AU335i]

Originally Posted by Jeff@topgearsolutions

Spraying a smaller M5 nozzle might benefit for heat soak otherwise the only benefit would be to increase ignition and maybe more top end boost. But you know this already.

if you were referring to my post, I meant more of a comparison to see if it effected my performance in a negative way like themyst is saying might be happening with cobb stage 2 + meth

[tibra1]

Originally Posted by Jeff@topgearsolutions

Spraying a smaller M5 nozzle might benefit for heat soak otherwise the only benefit would be to increase ignition and maybe more top end boost. But you know this already.

K.. yes the theory says so..but in the case of the COBB tune we have evidence to the contrary...so I am def interetsed to know why...I realize that if you dont have a tune set-up for meth/race fuel.. it would detract from expected results...but in this case we seem to have engine parameters going 180 degrees the opposite way..

A reflash tune that sees little to no timing drops in hotter ambient temp vs cooler ambient temp will not have a remedy w meth/race fuel etc..if anything I would expect that a reflash-tune (being that it is pump gas tune) would simply not be able to take advantage of meth/race-fuel..and as result make the same or more conservative logs.

But here we have timing drops in cooler weather vs hot weather...as opposed to just less power or less boost being made..something doesnt add up..

[themyst]

basically in a nutshell, running meth on this map is pointless unless someone can show otherwise.

[Bash]

Myst, i thought you were going to do a comparison between Jb4 and the stages of Cobb on the dyno, is that still on your schedule?

[themyst]

Originally Posted by Bash

Myst, i thought you were going to do a comparison between Jb4 and the stages of Cobb on the dyno, is that still on your schedule?

was going to do it last saturday, but the dyno was booked.

[themyst]

Originally Posted by tibra1

K.. yes the theory says so..but in the case of the COBB tune we have evidence to the contrary...so I am def interetsed to know why...I realize that if you dont have a tune set-up for meth/race fuel.. it would detract from expected results...but in this case we seem to have engine parameters going 180 degrees the opposite way..

A reflash tune that sees little to no timing drops in hotter ambient temp vs cooler ambient temp will not have a remedy w meth/race fuel etc..if anything I would expect that a reflash-tune (being that it is pump gas tune) would simply not be able to take advantage of meth/race-fuel..and as result make the same or more conservative logs.

But here we have timing drops in cooler weather vs hot weather...as opposed to just less power or less boost being made..something doesnt add up..

It's as if the tune (at least based on this log) is not pulling fuel to compensate for the meth being injected, which is causing the car to run a point richer than intended, which in most cases, is causing the car to run slower.

I was considering running meth in the colder temps to keep the engine happy, but if all it's doing is making the car run richer in this weather, then well, it's not doing squat. Could also require that I do some more runs for adaptation purposes. Who knows.

[Jeff@TopGearSolutions]

Originally Posted by AU335i

if you were referring to my post, I meant more of a comparison to see if it effected my performance in a negative way like themyst is saying might be happening with cobb stage 2 + meth

Sorry it was meant for the OP....

Originally Posted by tibra1

K.. yes the theory says so..but in the case of the COBB tune we have evidence to the contrary...so I am def interetsed to know why...I realize that if you dont have a tune set-up for meth/race fuel.. it would detract from expected results...but in this case we seem to have engine parameters going 180 degrees the opposite way..

A reflash tune that sees little to no timing drops in hotter ambient temp vs cooler ambient temp will not have a remedy w meth/race fuel etc..if anything I would expect that a reflash-tune (being that it is pump gas tune) would simply not be able to take advantage of meth/race-fuel..and as result make the same or more conservative logs.

But here we have timing drops in cooler weather vs hot weather...as opposed to just less power or less boost being made..something doesnt add up..

Well I think the consensus is it is making the car run entirely too rich spraying TOO much methanol. But at any rate its quite obvious too me why there is no advantage. These are pump gas maps, we all know methanol is a fuel and the only way higher octane will help is if ignition and or boost is increased, which its not.

If we could log the fuel trims and see that the DME cant take out enough fuel that will likely answer more questions.

As I mentioned previously spraying an M5 or even M3 nozzle might show benefits atleast for heat soak purposes but that is about it.

I say this all the time methanol on its own really adds no power, only when increasing ignition and boost.

In regards to cooler temps, its probably changing the load tables and those arent refined enough cause Cobb doesnt have access to those colder climates? or.... something in regards to IAT compensation needs to be changed. This car is too complex to start guessing. Just need more data in logs.

Originally Posted by themyst

basically in a nutshell, running meth on this map is pointless unless someone can show otherwise.

Spray less

[themyst]

Originally Posted by Jeff@topgearsolutions

Sorry it was meant for the OP....

Well I think the consensus is it is making the car run entirely too rich spraying TOO much methanol. But at any rate its quite obvious too me why there is no advantage. These are pump gas maps, we all know methanol is a fuel and the only way higher octane will help is if ignition and or boost is increased, which its not.

If we could log the fuel trims and see that the DME cant take out enough fuel that will likely answer more questions.

As I mentioned previously spraying an M5 or even M3 nozzle might show benefits atleast for heat soak purposes but that is about it.

I say this all the time methanol on its own really adds no power, only when increasing ignition and boost.

In regards to cooler temps, its probably changing the load tables and those arent refined enough cause Cobb doesnt have access to those colder climates? or.... something in regards to IAT compensation needs to be changed. This car is too complex to start guessing. Just need more data in logs.



Spray less

I have a DO1 nozzle sitting here waiting for testing.

[acdHQK713K]

Originally Posted by themyst

basically in a nutshell, running meth on this map is pointless unless someone can show otherwise.

Can you do me a huge favor before I go spend time installing my DO meth kit.

Can you run some 91 octane fuel and the meth kit on the aggressive stage 2+ map and log it. Just curious what you would find in that case. I am suspecting about the same as your initial logs.

Send me your logs and I will put it through the virtual dyno.

[themyst]

Originally Posted by Stangorang

Can you do me a huge favor before I go spend time installing my DO meth kit.

Can you run some 91 octane fuel and the meth kit on the aggressive stage 2+ map and log it. Just curious what you would find in that case. I am suspecting about the same as your initial logs.

Send me your logs and I will put it through the virtual dyno.

I don't have 91 octane around here, sorry.

[remington109]

So, meth is pointless until ATR?

[Brey335i]

Originally Posted by remington109

So, meth is pointless until ATR?

It's pretty pointless unless you have a map that requires the use of meth. My timing looks beautiful these days and the car pulls incredibly hard. Perhaps Rob will find some more power and let us know how his meth testing went. Curious to know what kit he chose.

[themyst]

A little update on meth testing with stage 2.

Looks like extensively running meth injection on stage 2 then disabling it does some wacky things to short-term fuel trims and AFR.

It seems after testing a 3-4 shift on stage 2 with meth turned off(edit), AFRs are off ever-so-slightly on the two banks and running in 11.1 - 11.6's (expected range is 11.8 - 12.4), and STFTs are maxed out on bank 2 at 34.22%.

After testing on meth (until my time on the dyno proves otherwise) I say if you're going to run meth on stage 2, do it all the time, otherwise simply don't bother. I'm going to log multiple WOT pulls with meth turned off to see if the trims and AFRs go back to expected levels.

Here is a log of stage 2 with meth turned off a day before with no WOT activity in between. Gotta love Cobb AP logging! You know what's going on and can make sense of it all.

PS. @Ilma I didn't flatline timing post-shift as you can see

[dzenno]

Interesting results man...i always wondered what happened with trims between switching on and off meth but keep in mind those are short term adjustments...the key thing is of course AFR...how quickly do they stabilize after shutting off meth?

[themyst]

Originally Posted by dzenno

Interesting results man...i always wondered what happened with trims between switching on and off meth but keep in mind those are short term adjustments...the key thing is of course AFR...how quickly do they stabilize after shutting off meth?

Thing is, they didn't. Even with the meth turned off, AFRs were in the same range as they were on meth. I'll give it 4-5 more good romps off meth to see if the AFRs stabilize back to the expected range.

[Brey335i]

So it adjusts to the meth and then takes some time to adjust back to non-meth?

[themyst]

Update: My AFRs never actually recovered from these runs. I was pegging low to mid 11 AFRs over and over with no meth. I just unmarried and reinstalled the AP and stage 2+ maps and AFRs are now 11.8-12.0, within spec.

Definitely not recommending running meth on Stage 2 for sure, at least based on my experience.

[dzenno]

Originally Posted by themyst

Update: My AFRs never actually recovered from these runs. I was pegging low to mid 11 AFRs over and over with no meth. I just unmarried and reinstalled the AP and stage 2+ maps and AFRs are now 11.8-12.0, within spec.

Definitely not recommending running meth on Stage 2 for sure, at least based on my experience.

really no point in meth here unless you run a small nozzle like an M3 or M5 and just 50/50 meth for IAT reduction...

[acdHQK713K]

Originally Posted by themyst

Update: My AFRs never actually recovered from these runs. I was pegging low to mid 11 AFRs over and over with no meth. I just unmarried and reinstalled the AP and stage 2+ maps and AFRs are now 11.8-12.0, within spec.

Definitely not recommending running meth on Stage 2 for sure, at least based on my experience.

Did you try the ECU reset function in the AP first? I actually have no idea what it resets, just curious if that would have done the trick.

[Ilma]

Originally Posted by themyst

A little update on meth testing with stage 2.



PS. @Ilma I didn't flatline timing post-shift as you can see

Yet you did while running meth..........
.
.
.

[themyst]

Originally Posted by Stangorang

Did you try the ECU reset function in the AP first? I actually have no idea what it resets, just curious if that would have done the trick.

I've tried the ecu reset, reloading the map itself, multiple wot pulls, nothing worked. I suspect if I could have reset lambda adaptations it may have helped but I don't have that luxury anymore. Whatever uninstalling/reinstalling did helped or so I hope.