under 90% is recommended

 

Yea I figured that. I pulled logs my IDCs are 98%. This is with the Cobb stage 1 91 tune, while using 93 octane.

 

How much boost are you hitting?

 

98% on a stage 1 tune! wow didnt think it'd be that much. And why arent u using the 93 octane tune if your using 93..?

 

This is by 7k redline. Peak boost is 16.8 or something like that. I don't have the exact numbers in front of me right now. It wasn't higher than 16.8, I do know that. I'm using 91 tune b/c I wanted to use that extra octane as an buffer to "richen" the car up. I k ow these cars run lean, so I wanted to have a small window.

 

Someone with more experience in tuning can correct me if I'm wrong, but I'm fairly sure that octane rating is not going to affect your A/F ratio, or as you put it "richen the car up."

 

I pulled logs for both tunes. Knock isn't the issue in either tune. Ill post both with I get to my computer, but the question was the duty cycle of the injectors; why are they almost maxed out? Is this normal? What are the size of the stock injectors?

 

If there was no knock when running the 93 tune, and you use 93 gas, you should just run the 93 tune. If you are concerned that it might lean the car out too much, contact Cobb and ask them how the a/f ratios differ between the 91 and 93 tunes. Or save some money and just buy 91 gas for the 91 tune. Running 93 octane gives no additional benefit if you are on the 91 tune with no knock issues.

To your questions: All you have is a stage 1 tune, no other mods? If so, that seems not normal. Stock injector size is 565 I believe.

 

It doesn't seem normal to me - it is too high.

Was the duty cycle lower with the 93 map? If it is a leaner map....

 

It doesn't seem normal to me - it is too high.

Was the duty cycle lower with the 93 map? If it is a leaner map....

This. Use the 93 map. The 91 is richer. Plus OTS maps will run rich. I would see about getting a custom tune. Also colder weather = higher duty cycles.

 

16.8 psi seems high for a stage I tune, but I think that may be normal for the new maps.

The injectors should be <90 on a stage II map, so there is something funny going on for sure.

 

Unfortunately, the new ATR won't allow me to view the 2012 maps, but classically, Cobb has traded very rich fueling for added timing.

 

I can't remember the IDCs on the 93 tune. Ill pull a new log. I don't think I monitored that on the first log I pulled with the 93 tune. If I recall correctly I only monitored the IDCs on the 91 tune. So you're saying since there isn't a knock issue, using a higher octane on a lower map isn't producing any benefits?

 

Upload your log to Google Docs and set it to Public. That's impossible to parse

 

This is the stage 1 91 octane tune

https://docs.google.com/spreadsheet/ccc?key=0Arx8vAWiV4xTdHdSWEpSZ3JHZy0xRE1EcjNZVzJZWlE

 

You have to make it public still I think.

A log with the 93 octane map is the one we need to see, but I'll be happy to look at the 91 map too.

 

Ok done. It's public. A 93 map will have to wait until tomorrow. The log I have doesn't have IDCs on it.

 

Yeah, nothing to see there really except the high duty cycle - it looks fine to go ahead and load the 93 map.

One weird learned knock "event" but it looks like it was right when you are lifting off and is probably insignificant.

 

Ill pull a 93 oct log and post it tomorrow. The knock learning was when I let off I did see that. A reason why I am running the 91 oct tune is b/c it boosts less than the 93 oct tune. I was under the impression that it will be richer than the 93 tune. Make sense?

 

run the 93 map. Seriously, the ots maps are rich enough that you can get away with running 92 on the 93 map. I must have logged about 90 times over a few months and never found anything too odd about the 93 map other than its pig rich to begin with. The 91 map is even worse.

Seriously cobbs maps are very very very lax. You can run that 93 map without issue.

 

Ok cool. How are your IDCs?

 

This is the stage1 93 octance tune. I'm hitting the same amount of boost as the other tune and duty cycle is around 96% at 6800 rpm

https://docs.google.com/spreadsheet/ccc?key=0Arx8vAWiV4xTdFJoS05TV1E5LWxPb01LMzVXazFjTUE#gid=0

 

That looks a bit better and I would stick with the 93 over the 91. Basically everything else is fine, so if you want to keep running it you have to keep an eye on it and make sure it isn't leaning out when the weather gets colder or anything else that might make your boost go up. You're not quite making the target boost but I wouldn't try without upgrading the fuel system. Also note that the factory front O2 isn't accurate at WOT - no point in logging that and don't rely on it. Watch for changes to the DAM and knock cells instead.


I still find it strange that the duty cycles are so high on a stage II map. You really would likely be better served with a more custom map.

 

I did see that this tune looks better. I will leave it, but my IDCs are better b/c I'm not hitting targeted boost levels. I think if I was they would be closer to maxed out.

 

It's a stage 1 map tho

 

To bring back an old thread....

I've got a 2013 5 door....stage 1...running Cobb Stage 1 91 octane, modified by e-tuner to run 16 lbs. of boost.

My logs show at 6k rpm, I'm at 86% injector duty cycle. I'm at about 11.2 AFR at that point (tailpipe sniffer at dyno). Is this too rich?

How are people running a stage 2 tune on stock fuel pump and stock injectors?