Anyone with Unitronic Stage 2+ running on 91?

[Bartlett]

Hi all,

I was just wondering who here has the entitled tune + octane setup that may have done some logging? I'm seeing timing pull of about 5 to 7 degrees on Shell 91, and I feel like this is a bit laughable for only 2 octane variance. The tune should be adjusting for a couple octane variance IMO. It even seems that Unitronic mentioned that it would be okay. Given this, I would expect practically no timing pull because the spark table would be different for the 91.

John said here:

"Our Stage 2+ Performance Software is optimized for 93 octane, but can be used with 91 octane for folks that don't have access to 93. Stage 2+ results on 91 octane will be a bit reduced than the above figures considering the lesser fuel grade."

But, based on this statement, it seems like it will use the same table and pull timing (my scenario I suppose?). But, "with quality 91", it seems like it may not happen. I'm not sure how much more "quality" I can get in my area than 91 from a popular, well-rated Shell gas station.

"Yes, the ECU will apply correction (pull timing). There is a limit on how much the ECU can adapt, but using quality 91 octane shouldn't reach those thresholds."

FWIW, I have NGK PFR8S8EG plugs gapped to .028, my IATs do not pass 70C, and my valves do not have carbon build-up. I am also getting an occasional misfire on a cylinder due to the degree of timing retardation.

[bhvrdr]

Some 91 octane is junk. There are bone stock California car logs on this forum showing 12-13 degrees timing pull. Id not be concerned myself. The ikc system in this car is extremely safe. The timing being pulled out is preventing dangerous knock meaning you arent having it.

You are not getting a misfire from 5-7 degrees retard. You're getting it for some other reason so start the diagnistics on that cylinder. How many misfires on cyl 1? Do you get a soft code on it or full cyl disabling?

All this said if you really want a lower timing file dont they have stage 2 instead of 2+. Just flash it on.

Mike

[theweebabyseamus]

Doesn’t seem that odd to me, there’s some 91 maps that get timing pull on 91 as intended operation. And then there’s the above mentioned by Mike.

[Bartlett]

Some 91 octane is junk. There are bone stock California car logs on this forum showing 12-13 degrees timing pull. Id not be concerned myself. The ikc system in this car is extremely safe. The timing being pulled out is preventing dangerous knock meaning you arent having it.

You are not getting a misfire from 5-7 degrees retard. You're getting it for some other reason so start the diagnistics on that cylinder. How many misfires on cyl 1? Do you get a soft code on it or full cyl disabling?

All this said if you really want a lower timing file dont they have stage 2 instead of 2+. Just flash it on.

Mike

So you're saying that running the car hard for months or years on 5 to 7 degrees of pulled timing is of no concern?

And I found that cylinder 2 is the one misfiring. I keep getting 1 misfire per timestamp on turbo mode, as reported by Misfires cylinder 2 per 1000 rpm

During this logging session, it occurred between 700 and 2000 RPMs. During another one, 5000 to 6000 RPMs. It seems to occur in groups too..like it's not randomly throughout my logging session, but concentrated throughout X contiguous milliseconds.

Doesn’t seem that odd to me, there’s some 91 maps that get timing pull on 91 as intended operation. And then there’s the above mentioned by Mike.

And same question for you then: can I run the car hard for months or years on 5 to 7 degrees of pulled timing without concern?

[ModItNow]

Go down in gap on cyl 2 by. 001" at a time and see if the misfire goes away. I ran a 93 tune with 91 but ran 3-3.5 gallons of e85

Sent from my SM-G965U using Audizine mobile app

[bhvrdr]

Good idea.

And no there is no issue running 5-7 retard. Again ive seen logs of California bone stock cars retarding 12 degrees and as long as they keep living in that area and filling upnat that station the car will be operating like that its entire life.

That said i read that you recently got a bad tank of fuel. Run some bg44k through a tank of gas

Also if you are seeing not even softcodes for misfires then thats not too much od an issue. Every car has an occasional misfire. The car will first throw a softcode if its excessive and will eventually even give you blinking cel and limp mode.

If you find your fuel quality is consistently poor where you live just flash the file with less timing.

Mike

[Bartlett]

Go down in gap on cyl 2 by. 001" at a time and see if the misfire goes away. I ran a 93 tune with 91 but ran 3-3.5 gallons of e85

Sent from my SM-G965U using Audizine mobile app

Good idea. I'll be able to add E98 usually, but it's not the most convenient thing.

And currently all are gapped to .028", but I'll try .029" on that one after I do a few other troubleshooting things.

Good idea.

And no there is no issue running 5-7 retard. Again ive seen logs of California bone stock cars retarding 12 degrees and as long as they keep living in that area and filling upnat that station the car will be operating like that its entire life.

That said i read that you recently got a bad tank of fuel. Run some bg44k through a tank of gas

Also if you are seeing not even softcodes for misfires then thats not too much od an issue. Every car has an occasional misfire. The car will first throw a softcode if its excessive and will eventually even give you blinking cel and limp mode.

If you find your fuel quality is consistently poor where you live just flash the file with less timing.

Mike

Sounds good, I guess I'll just be doing the 93 map on 91, and accepting the pulled timing whenever I don't have ethanol.

And what's the recommended procedure with bg44k? Add the bottle before a fill-up and drive like one would normally?

And I have yet to get a CEL, or any codes. So far, for troubleshooting I am going to (not in any particular order):

- swap plug and coil pack of cylinder 2 with cylinder 5 or 6.
- borescope the cylinder
- check fuel injector
- increase spark plug gap

[bhvrdr]

Sounds great. Yes just add it at the gas station to an empty tank. Throw 10 orc12 gallons on it and then run that tank empty

[Bartlett]

Go down in gap on cyl 2 by. 001" at a time and see if the misfire goes away. I ran a 93 tune with 91 but ran 3-3.5 gallons of e85

Sent from my SM-G965U using Audizine mobile app

Good idea.

And no there is no issue running 5-7 retard. Again ive seen logs of California bone stock cars retarding 12 degrees and as long as they keep living in that area and filling upnat that station the car will be operating like that its entire life.

That said i read that you recently got a bad tank of fuel. Run some bg44k through a tank of gas

Also if you are seeing not even softcodes for misfires then thats not too much od an issue. Every car has an occasional misfire. The car will first throw a softcode if its excessive and will eventually even give you blinking cel and limp mode.

If you find your fuel quality is consistently poor where you live just flash the file with less timing.

Mike

Sounds great. Yes just add it at the gas station to an empty tank. Throw 10 orc12 gallons on it and then run that tank empty

Will do, thanks! I'll keep ya posted.

[Bartlett]

Sounds great. Yes just add it at the gas station to an empty tank. Throw 10 orc12 gallons on it and then run that tank empty

So, after some more research, I've concluded:

- Can't run Stage 2+ 93 tune on 91 without getting 7-9 degrees of timing pulled
- When I had ~0 degrees timing pulled each time I logged on Stage 2+ 93, coincidentally I had E20 + in my tank
- 7-9 degrees of timing pulled will increase my IATs
- Stage 1 91 tune is about 85% - 90% of the Stage 2+ tune in terms of performance and I see 0-3 degrees pulled on 91
- 2 weeks ago, I added BG 44k prior to a fill-up and ran the tank near empty - I did this twice
- E20 93 octane (12 gal 91, 2.5 gal E98) is still showing 3-4 degrees timing pulled, but it's not that frequent (see logs below)
- Today, I logged for 45 minutes on E20 (same gas above) and saw 1 misfire for 15 seconds during deceleration as well as a few degrees of timing pulled

Attached the 45 min log below:
https://www.mediafire.com/file/aarav..._e98.xlsx/file

I'm confused as to why with my IATs I am seeing timing pulled on E20, and why I am seeing a misfire logged on E20 + after 2 rounds of BG 44k, new coils, and spark plugs less than 8 months old with .028" gap, OEM heat range.

[bhvrdr]

So, after some more research, I've concluded:

- Can't run Stage 2+ 93 tune on 91 without getting 7-9 degrees of timing pulled
- When I had ~0 degrees timing pulled each time I logged on Stage 2+ 93, coincidentally I had E20 + in my tank
- 7-9 degrees of timing pulled will increase my IATs
- Stage 1 91 tune is about 85% - 90% of the Stage 2+ tune in terms of performance and I see 0-3 degrees pulled on 91
- 2 weeks ago, I added BG 44k prior to a fill-up and ran the tank near empty - I did this twice
- E20 93 octane (12 gal 91, 2.5 gal E98) is still showing 3-4 degrees timing pulled, but it's not that frequent (see logs below)
- Today, I logged for 45 minutes on E20 (same gas above) and saw 1 misfire for 15 seconds during deceleration as well as a few degrees of timing pulled

Attached the 45 min log below:
https://www.mediafire.com/file/aarav..._e98.xlsx/file

I'm confused as to why with my IATs I am seeing timing pulled on E20, and why I am seeing a misfire logged on E20 + after 2 rounds of BG 44k, new coils, and spark plugs less than 8 months old with .028" gap, OEM heat range.

1. Yes don't run a 93 file with 91 in the tank. Run the 91 file when 91 is in the tank. Edit: as you've found you can run the 93 file but you're just going to get more timing pull so no reason to

2. 2-3 degrees pull is fine

3. No 7-9 degrees pull is not raising iats. High iats will contribute to reduced timing not the other way around

4. 1 misfire in a 40 min session is normal.

5. How is the car driving running the 91 file on 91 octane? This should be what is right and logs look fine.

Mike

Sent from my SM-G935V using Tapatalk

[Bartlett]

1. Yes don't run a 93 file with 91 in the tank. Run the 91 file when 91 is in the tank. Edit: as you've found you can run the 93 file but you're just going to get more timing pull so no reason to

2. 2-3 degrees pull is fine

3. No 7-9 degrees pull is not raising iats. High iats will contribute to reduced timing not the other way around

4. 1 misfire in a 40 min session is normal.

5. How is the car driving running the 91 file on 91 octane? This should be what is right and logs look fine.

Mike

Sent from my SM-G935V using Tapatalk

1) I will try adding another half gallon of E98. Depending on the timing, I may go back to Stage 1 91.

2) Yes, I can probably agree.

3) But, there is less extraction of mechanical energy from a given amount of heat release. Exhaust gas temperature will probably be higher too.

4) Good to know. What makes you say that though?

5) It should absolutely be 0 timing pulled on Stage 1 91 with E20. It drives pretty alright on 91, but the file seems to slightly lack torque.

[bhvrdr]

1) I will try adding another half gallon of E98. Depending on the timing, I may go back to Stage 1 91.

2) Yes, I can probably agree.

3) But, there is less extraction of mechanical energy from a given amount of heat release. Exhaust gas temperature will probably be higher too.

4) Good to know. What makes you say that though?

5) It should absolutely be 0 timing pulled on Stage 1 91 with E20. It drives pretty alright on 91, but the file seems to slightly lack torque.

1-2. Awesome

3. Look at it this way. Lets say the 93 file is requesting 20 degrees timing but your fuel quality only allows for 13 degrees so youre going to see 8 degrees retard. Lets say the 91 file requests 16 degrees timing so you're only retarding 3 degrees now with that same fuel that allows for 13 degrees of timing. Its the same toming you're running

4. Every car ive logged is going to show some type of misfire activity in a long drive. The simos has different levels of warning and protection for abnormal levels of misfires. First youll see a softcode stored in the ecu when you check for codes stating the cyl and abnormal misfire activity. Next youll get a cel. Finally youll get limp mode. If youre showing zero soft codes and having zero stumbles, hesutation, etc you're fine

5. Sweet.

[Bartlett]

1-2. Awesome

3. Look at it this way. Lets say the 93 file is requesting 20 degrees timing but your fuel quality only allows for 13 degrees so youre going to see 8 degrees retard. Lets say the 91 file requests 16 degrees timing so you're only retarding 3 degrees now with that same fuel that allows for 13 degrees of timing. Its the same toming you're running

4. Every car ive logged is going to show some type of misfire activity in a long drive. The simos has different levels of warning and protection for abnormal levels of misfires. First youll see a softcode stored in the ecu when you check for codes stating the cyl and abnormal misfire activity. Next youll get a cel. Finally youll get limp mode. If youre showing zero soft codes and having zero stumbles, hesutation, etc you're fine

5. Sweet.

3) That does make sense, and that's what I thought at first. But, to me it doesn't seem like it's simply a matter of the effective ignition angle. I'm thinking that existence of correction is the distinct reason why IATs would be higher. These are just my thoughts after random reading over the months.

4) Sounds good to me. I haven't gotten any codes, so it looks like I'm in good shape