[Vwgrk1]

I have a feeling that tuning in this heat is a waste of time, unless one wants to loosen up the CAT ignition reduction safeguards. I am too much of a chicken to do so. The thing is, I've gone ahead and added 5 or 6 degrees of timing in the higher loads (I am hitting those loads), but my actual cyl 1 timing is only a degree or so higher than the off the shelf 401 map. This seems to be because high CAT (110 to 160 degrees) is triggering the safeguard, reducing timing by a large factor. Any veterans want to share their thoughts? Am I wasting my time?

My quest might have to wait until fall. I don't want to add 6 degrees of advance now and get nasty knock when temps fall and the computer actually runs those 6 extra degrees while I am not logging. I can totally see why people go meth and bigger intercooler.

At the end of the day, I am not comfortable with runs in the 140 and up range, either. My car is stock outside of the Cobb. FWIW, running 7 gallons of E85 over 93 octane on the regular 401 map (only change having been made to account for the fuel mixture) showed absolutely no timing corrections in 10 WOT runs, even in this heat. E85 is the real deal...I think I have to wait for the cold before I unlock its potential, though.

[Slidewayz]

No, it is not 'futile'. It is 'necessary'.

[benzy89]

Try tuning it at night when it's a little cooler. If anything it's better to tune at non-ideal conditions so the car isn't more susceptible to knock/over aggressive timing.

Obviously the car will run it's best during 50-60* temps, so tuning it at 100* will give you the appropriate tune for those conditions. With the same tune, the car will give a few more ponies back & run smoother (cooler IAts = more hp, better operating temps & a happy car)

[Joshboody]

if you really want to be precise, map it on paper with these 2 tables and correlate to the logs. You can't extrapolate one weather condition to another except for the basic curve.. the actual values need to be determined from logging. Keep in mind that load can also be altered per temp by "load target limit".

[Dethsupp0rt]

I feel ya. Same car, same place, same setup (I'm only running 25% E85 though), and it seems like the bottleneck is now the stock intercooler. I plan on rectifying that in the next couple of weeks.

[dfv2]

This engine is a dog in the heat. I'd be careful about piling on the advance while corrections are heavy, because once it cools off you will be running more advance than you've ever actually logged/tuned for. On E85 you may reach MBT without seeing significant timing corrections, and you will be boost limited by hardware. So you may even be over-advancing and losing power at this point. Post logs.

[Carl Morris]

Depends on what you're trying to accomplish. I've been able to learn a lot about how much timing needed pulled due to heat as I've logged in the 70s on the way to work and the 90s on the way home. But yeah, between the reduced timing required and the lower air density, power is down significantly. No point in going to the track or the dyno for glory numbers in the heat.

[benzy89]

Originally Posted by Dethsupp0rt

I feel ya. Same car, same place, same setup (I'm only running 25% E85 though), and it seems like the bottleneck is now the stock intercooler. I plan on rectifying that in the next couple of weeks.

The Stock FMIC is probably the 2nd most restrictive part of the car that is normally modded (after the downpipes). It's way to susceptible to heatsoak & really doesn't cool your IATs down like an aftermarket 5" core will

[Vwgrk1]

Originally Posted by Joshboody

if you really want to be precise, map it on paper with these 2 tables and correlate to the logs. You can't extrapolate one weather condition to another except for the basic curve.. the actual values need to be determined from logging. Keep in mind that load can also be altered per temp by "load target limit".

I actually did that, lol. It explained the low timing almost spot on.

[Vwgrk1]

Originally Posted by benzy89

Try tuning it at night when it's a little cooler. If anything it's better to tune at non-ideal conditions so the car isn't more susceptible to knock/over aggressive timing.

Obviously the car will run it's best during 50-60* temps, so tuning it at 100* will give you the appropriate tune for those conditions. With the same tune, the car will give a few more ponies back & run smoother (cooler IAts = more hp, better operating temps & a happy car)

I am with you on this; I am sure that even this tune with its rather mild adjustments will yield much more power as it gets colder. In other words, what is not so noticeable now will be as it gets colder. Trouble is that it is barely cooler at night while I am awake and there is either traffic or construction at all times, lol (Chicago).

I am starting to feel certain that I am better-served by tuning in the cold and adjusting that tune as it gets warmer.

[Vwgrk1]

Originally Posted by dfv2

This engine is a dog in the heat. I'd be careful about piling on the advance while corrections are heavy, because once it cools off you will be running more advance than you've ever actually logged/tuned for. On E85 you may reach MBT without seeing significant timing corrections, and you will be boost limited by hardware. So you may even be over-advancing and losing power at this point. Post logs.

I am with you 100%...maybe it's because we are from the Subie world (you want a dog in the heat...drive my old 18G WRX, lol).

Here's a couple logs. Run 2 is a higher boost / slightly advanced timing map. Ethanol content was only about 25% and there was clearly room (I was testing STFT at the time, before the adjustment came out). Run 19 is the 401 map with about 40% E85 in the tank.

My additional timing request came through in run 2. My concern is more over insane CATs.

[Vwgrk1]

Originally Posted by Slidewayz

No, it is not 'futile'. It is 'necessary'.

Reading my original post, I guess I was not clear. My other issue is that all these runs are under high CATs, which makes me nervous...it isn't just the timing adjustment, which is a hard number as opposed to a % reduction. Not sure that it is worth the risk. You know what I mean, or am I making more if it than I should?

[georgelb]

I wanted to do some E85 tuning this week too, but I think this is more of a baby the car week.

[Dethsupp0rt]

Originally Posted by georgelb

I wanted to do some E85 tuning this week too, but I think this is more of a baby the car week.

Just brutal. Take care of yourself (and your car) in this heat, man.