GTIfan99 mk8 GTI 380 S review and "build" thread.

[mrmatto]

With DSG, are you feeling any big drop off in 3rd, probably 4th for you, based on gearing?

Yeah 3rd feels pretty good. Top of 3rd starts to feel the heat if it’s warmer out. But not too noticeable.

 

[GTIfan99]

Yeah 3rd feels pretty good. Top of 3rd starts to feel the heat if it’s warmer out. But not too noticeable.

I'm going to miss the 16th, but I can't wait to hear how your car feels on course.

 

[mrmatto]

Look at the mk8 vs mk7 dyno power band too. There’s a difference there we might just not be used too. More top end pull with a little less 3-3.5k.

 

[mrmatto]

I'm going to miss the 16th, but I can't wait to hear how your car feels on course.

I’m likely gonna miss it too lol

 

[GTIfan99]

I’m likely gonna miss it too lol

We're slackers.

Remember last month when I bought 245 40 17 RE71RS's over the V730, because they were same price in 17's?

235 35 19 there's a $100 per tire difference. Still went with the stones, they were so impressive in the month I had them, I just bit the bullet.

 

[mrmatto]

We're slackers.

Remember last month when I bought 245 40 17 RE71RS's over the V730, because they were same price in 17's?

235 35 19 there's a $100 per tire difference. Still went with the stones, they were so impressive in the month I had them, I just bit the bullet.

Damn dude . Open your own tire shop already.

 

[scrllock]

You're probably right, but was looking at the 2 piece, some titanium spacers, RS3 deflectors, because I'm going to have to use the stock calipers. I'd keep the 2 piece for track only and use stockers for street and autocross, you're probably right, blanks make more sense.

i switched to blanks because the only 2pc fcp stocks in 340mm are 034 shit, at least from what i found

 

[GTIfan99]

i switched to blanks because the only 2pc fcp stocks in 340mm are 034 shit, at least from what i found

I was mistaking the mk8 R rotors, which are 357mm. You're right, they don't have them. ECS seems to seem the CS 2 piece though.

You're probably right though. Blanks are the route I'll probably go.

 

[GTIfan99]

Yeah 3rd feels pretty good. Top of 3rd starts to feel the heat if it’s warmer out. But not too noticeable.

So I filled up with 93 Oct and ran the car a couple of days. I know it's tuned to run on 87, but 3rd gear feels much better with 93. It must have been pulling timing and/or boost.

 

[mrmatto]

So I filled up with 93 Oct and ran the car a couple of days. I know it's tuned to run on 87, but 3rd gear feels much better with 93. It must have been pulling timing and/or boost.

Makes sense. I’ve been running 89 and it seems to do well. 93 is prob overkill but who knows.

 

[scrllock]

So I filled up with 93 Oct and ran the car a couple of days. I know it's tuned to run on 87, but 3rd gear feels much better with 93. It must have been pulling timing and/or boost.

From what we know 2019+ cars have a high-octane learning mode, so they should be adding at least a few degrees of timing on premium.

 

[mrmatto]

From what we know 2019+ cars have a high-octane learning mode, so they should be adding at least a few degrees of timing on premium.

I don't know if that's the same on the mk8. A few people have dyno'ed these engines on 87 vs. 93 and there's essentially no power difference. The main thing I noticed in those videos was the higher octane fuel produced more consistent runs, which supports @GTIfan99's experience above trying out 93, and it supports my experience with 89.

Obviously higher octane is less likely to result in knock and timing pull when IAT's go up. But, there is a limit to this because the ECU uses IAT timing tables that will automatically pull some timing advance when IAT's go up anyways as a precaution. But it's controlled and predictable. Conversely, a single knock event usually results in -3* of sudden timing pull that lasts for several hundred RPM. That's a noticeable power suck. MOAR OCTANE PLZ.

 

[GTIfan99]

All the octanes pleaz

 

[scrllock]

I don't know if that's the same on the mk8. A few people have dyno'ed these engines on 87 vs. 93 and there's essentially no power difference. The main thing I noticed in those videos was the higher octane fuel produced more consistent runs, which supports @GTIfan99's experience above trying out 93, and it supports my experience with 89.

Obviously higher octane is less likely to result in knock and timing pull when IAT's go up. But, there is a limit to this because the ECU uses IAT timing tables that will automatically pull some timing advance when IAT's go up anyways as a precaution. But it's controlled and predictable. Conversely, a single knock event usually results in -3* of sudden timing pull that lasts for several hundred RPM. That's a noticeable power suck. MOAR OCTANE PLZ.

VanCity did shitty testing that likely wouldn't have triggered the high ron learning. He refused to acknowledge that he may have presented poor data and never re-tested. We would need a Simos19 FR to know for sure but I really doubt they took it out post-18.10.

 

[mrmatto]

VanCity did shitty testing that likely wouldn't have triggered the high ron learning. He refused to acknowledge that he may have presented poor data and never re-tested. We would need a Simos19 FR to know for sure but I really doubt they took it out post-18.10.

He's not the only one that's done a dyno test, and he did the same test on another vehicle (Audi something?) with the same results.

It doesn't make sense that VW would implement a tune that makes more power on higher octane and not use that in marketing or even mention it.

What "triggers" high ron learning? Based on what I know about the SIMOS setup on mk7/7.5, it's simply running aggressive knock detection to safely pull timing to safely run lower octane, and when high octane is run it just doesn't knock and pull timing. That would happen immediately. Is there something else in the tables for 2019+ mk7.5 that triggers different timing tables or something?