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

[GTIfan99]

All I know is it felt like ass in 3rd gear on 87, and felt significantly better with 93.

You could feel it pulling timing aggressively on 87, smooth and strong on 93.

I'd guess I was getting some knock and not getting knock on the higher octane.

The tank I was getting knock was from the dealer though, for all I know, they pissed in the tank.

 

[mrmatto]

Yeah, could be the difference between cheap gas and good gas too. Try 89 and see if the +2 octane has the same benefit for you.

 

[scrllock]

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?

Right, pre-18.10, they only did low ron. IIRC when @DerHase was testing (on his 18.10 car, 5G...295Q iirc), it would add up to 3 degrees in some parts of the load table. It wasn't consistent when it ran (which is why VanCity's refusal to even try it is not "proof" that it doesn't occur). It makes sense that we've only seen it on GTI/GLI cars that are intended to run regular, since those are commonly filled up with higher octane than required.

It's also not consistently turned on across all boxcodes, so one or two canadian cars also doesn't mean much. Given the possibility, I think it likely explains GTIfan99's improvement on 93. I'd be surprised if that function made it anywhere near a marketing person, tbh. It'd be akin to saying "oh, these ECUs have lambda-based flex-fuel" and you'd get a million people doing dumb stuff based on incorrect assumptions about what that implies.

 

[aspro_gti]

Whats DCC?

 

[GTIfan99]

Whats DCC?

Dynamic Chassis Control. Basically they have adjustable dampening that you can adjust from the cabin. They're also gas charged.

At the end of the day, the shocks resist dive, roll and squat better than the base Sach's shocks.

 

[mrmatto]

FWIW, I’ve noticed no difference on a tank of 93 compared to 89. Until someone can prove or quantify a benefit with running 93, I’m gonna stick with 89 going forward since it’s cheaper and seems to solve the occasional heavy-handed timing pull on 87.

 

[GTIfan99]

FWIW, I’ve noticed no difference on a tank of 93 compared to 89. Until someone can prove or quantify a benefit with running 93, I’m gonna stick with 89 going forward since it’s cheaper and seems to solve the occasional heavy-handed timing pull on 87.

That sounds reasonable to me.

Once I get past break in, I'm going 91 Oct Stg 1 high torque, so I'll just keep putting 93 in it.

I don't drive enough that the cost savings matter.

 

[GTIfan99]

Observations after 2 weeks of ownership.

I'm digging the higher powerband of the mk8 vs the mk7. It's just more usable and fun.

They really got the suspension tuning right for a road car.

The slightly firmer clutch and more consistent engagement makes a massive improvement over the mk7's setup, with no real downside. So much easier to drive around town.

I miss keyless entry more than I thought I would. I'm going to hit up DAP to see if I can retrofit.

Not sure if something is different with 2024, but my OBD11 won't talk to the car.

I think they're using a slightly less aggressive stock front brake pad. That, or the calibration of the abs/braking system requires more effort for the same braking force. Hard to really tell on the street. Easy to modulate though and firmer feel overall. Stock mk7.5 pp brakes felt like an on off switch stock and were hard to modulate


Overall, feels like a tighter mk7 with slightly bigger turbo. I'm liking the interior more than I thought I would. It's what I wanted the Rabbit Edition to feel like, but it never really got there. I went slightly over the mark and compromised it as a street car more than I wanted to and the brakes and clutch never felt decent. I don't regret selling the mk7.5, other than the fact it was paid off.

I'd give the car in this spec 9/10. 380 SE would solve the couple of gripes I have, no keyless entry and no wireless Android Auto, but then I'd be stuck with a sunroof. Overall really happy with the car.

When I get bored, I'm going to look at IC, mk8 CS springs, CS hubs, offset lca bushings and a titanium exhaust. I can't see pushing it power wise more than just a tune.

This car is ALMOST perfect out of the box. The Rabbit was significantly off the mark stock.

 

[Jmitchell4873]

Observations after 2 weeks of ownership.

I'm digging the higher powerband of the mk8 vs the mk7. It's just more usable and fun.

They really got the suspension tuning right for a road car.

The slightly firmer clutch and more consistent engagement makes a massive improvement over the mk7's setup, with no real downside. So much easier to drive around town.

I miss keyless entry more than I thought I would. I'm going to hit up DAP to see if I can retrofit.

Not sure if something is different with 2024, but my OBD11 won't talk to the car.

I think they're using a slightly less aggressive stock front brake pad. That, or the calibration of the abs/braking system requires more effort for the same braking force. Hard to really tell on the street. Easy to modulate though and firmer feel overall. Stock mk7.5 pp brakes felt like an on off switch stock and were hard to modulate


Overall, feels like a tighter mk7 with slightly bigger turbo. I'm liking the interior more than I thought I would. It's what I wanted the Rabbit Edition to feel like, but it never really got there. I went slightly over the mark and compromised it as a street car more than I wanted to and the brakes and clutch never felt decent. I don't regret selling the mk7.5, other than the fact it was paid off.

I'd give the car in this spec 9/10. 380 SE would solve the couple of gripes I have, no keyless entry and no wireless Android Auto, but then I'd be stuck with a sunroof. Overall really happy with the car.

When I get bored, I'm going to look at IC, mk8 CS springs, CS hubs, offset lca bushings and a titanium exhaust. I can't see pushing it power wise more than just a tune.

This car is ALMOST perfect out of the box. The Rabbit was significantly off the mark stock.

Glad to hear that you're happy with your decision.

My ideal spec would have been an anniversary edition car with cloth and manual since they included keyless entry without the moonroof. I never got the chance to see one in person though since they seemed to disappear quickly. I'll make due with my poverty spec S model as I continue to fumble for my keys as a I balance grocery bags.

 

[GTIfan99]

Glad to hear that you're happy with your decision.

My ideal spec would have been an anniversary edition car with cloth and manual since they included keyless entry without the moonroof. I never got the chance to see one in person though since they seemed to disappear quickly. I'll make due with my poverty spec S model as I continue to fumble for my keys as a I balance grocery bags.

I don't think US anniversary got keyless entry either.

Keyless comes on 380 SE and AB, so I should be able to get the door handles in Graphite Gray. I'm just hoping the modules are there already, because car knows when I walk up to it with my keys. I'm hoping it's plug, play and code for it.

 

[GTIfan99]

Got some information on mk8 CS springs.

Mk7 CS, mk7 CSS, mk7.5 TCR, mk8 GTI, and mk8 CS all use the same springs. CS, CSS and TCR use different rear sway and CS, CSS different hubs.

Mk8 R uses same front springs as all the models above.

So there's no OEM solution to lowering the car.

At the end of the day, the ride height it is stock is the best for performance. These cars don't like being lowered, it puts them in a bad part of the camber curve.

So rear sway bar looks like the right call.

 

[mrmatto]

Got some information on mk8 CS springs.

Mk7 CS, mk7 CSS, mk7.5 TCR, mk8 GTI, and mk8 CS all use the same springs. CS, CSS and TCR use different rear sway and CS, CSS different hubs.

Mk8 R uses same front springs as all the models above.

So there's no OEM solution to lowering the car.

At the end of the day, the ride height it is stock is the best for performance. These cars don't like being lowered, it puts them in a bad part of the camber curve.

So rear sway bar looks like the right call.

Did you get a PN for the CSS rear sway? Wondering how different it is from the GTI

 

[GTIfan99]

Did you get a PN for the CSS rear sway? Wondering how different it is from the GTI

I did find it, didn't book mark. It's not much bigger.

I'm going to probably go with the Neuspeed 24mm adjustable to start. .15 toe out front, zero toe and -1.8 camber rear. The mk7.5 was awesome with 26mm RSB and those settings, so I'll use this as a starting point.

When I eventually go to STH, I'll do Eurosport camber kit and offset LCA bushings again. If I do need more rear spring rates, I can always do like I did with the last car, and buy swift springs, a helper spring and adjustable threaded perch.

 

[aspro_gti]

At the end of the day, the ride height it is stock is the best for performance. These cars don't like being lowered, it puts them in a bad part of the camber curve.

So rear sway bar looks like the right call.

I'm not so sure. Lowering a car offers the advantage of lowering the center of gravity at the tradeoff of leaving your roll center behind (control arms now rest at a different angle), have an uneven loaded sway bar, and alignment issues.
There are fixes/bandaids to these.

Roll center - Can be mitigated with "roll center ball joints" which lengthen the control arm attach point which fixes their angle by a small amount. You can also just get a beefier sway bar so that you have better body roll resistance, although this comes at the cost of dropping the subframe for a time consuming job.

Uneven loaded sway bar - adjustable endlinks

Alignment issues - The car from factory is designed to be a fun daily driver and not a weekend track car, so adding some extra camber will benefit at the track but wear the inside of the tires a bit quicker. It's not that bad, and with adjustable coilovers you can raise the car when dailying and drop it + camber it for the track. Or you can get a camber plate, or the ball joints that slide a bit (cheaper and fix your roll center).

No doubt the car from factory has it's suspension tuned for great handling with good ground clearance, but that doesn't mean that lowering the car doesn't offer performance benefits.

 

[scrllock]

I'm not so sure. Lowering a car offers the advantage of lowering the center of gravity at the tradeoff of leaving your roll center behind (control arms now rest at a different angle), have an uneven loaded sway bar, and alignment issues.
There are fixes/bandaids to these.

Roll center - Can be mitigated with "roll center ball joints" which lengthen the control arm attach point which fixes their angle by a small amount. You can also just get a beefier sway bar so that you have better body roll resistance, although this comes at the cost of dropping the subframe for a time consuming job.

Uneven loaded sway bar - adjustable endlinks

Alignment issues - The car from factory is designed to be a fun daily driver and not a weekend track car, so adding some extra camber will benefit at the track but wear the inside of the tires a bit quicker. It's not that bad, and with adjustable coilovers you can raise the car when dailying and drop it + camber it for the track. Or you can get a camber plate, or the ball joints that slide a bit (cheaper and fix your roll center).

No doubt the car from factory has it's suspension tuned for great handling with good ground clearance, but that doesn't mean that lowering the car doesn't offer performance benefits.

None of the "roll center" balljoints on the market do shit to help anything besides add a bit of camber.
You also lose bump travel, of which we have precious little.

These cars perform very well near stock height, you'd end up dropping about $3k on the front half of the verkline catalog to actually correct the kinematics. Camber is much cheaper and efficient than fucking up the ride with lowering springs.