Jetta 118 Tsi - underground performance stage 1

[pocketpunch]

Hi team,

I'm back with a review of sorts.
I contacted Alex from Underground Performance on their Facebook page the other day and organised they do a simple stage 1 tune on the mk6 Jetta - Manual Transmission.

After an initial obd read, the map took about 25 minutes to be generated followed by you driving your car with Alex to log some data.

Now - to the juicy part.
I was charged $775 for the tune which puts it down to a great deal since its a custom written tune with your specific car in mind.
They look at the engines reaction to being subject to higher outputs and see if any problems can rise.
They prefer to make their power through fuelling and ignition optimisation rather than just ramping up the boost.

Anyway,

The car is incredible now.
It really feels like this is how it should have been from factory.
The pedal is now a linear input not that factory delayed response you get from the stock car.
The engine is really snappy to your inputs and the power delivery is savage.
The low end mostly feels the same but the car will now pull like a Mo#######er after 3000 Rpm.
It generates power to redline and doesn't bog out like the stock car did.

Haven't done a dyno, but we're definitely sitting on 200 Hp as this feels like a stock Gti now.

Only mods I've done was a dv+ and the plastic airbox grille delete.

Guys, seriously urge a good custom tune for the twinchargers - for those of you who have the latest generation of the engine ofcourse.

I'll record a few videos demonstrating the cars acceleration and post.

Any questions, fire away.

[pocketpunch]

Coming back with an update.

2 weeks in and the car is giving me no trouble.
I even had my car serviced and Vw mentioned nothing of my mods.
Fuel consumption has dropped slightly, I'm finding it very easy to manage 6.2L/100km in mixed conditions if I'm not being silly.
I've gone as low as 5.8 with a trip to Melbourne airport and through the city coming from S.E Suburbs.

The car warms up quicker but I always drive gently until it's up to operating temp.
Oil temperatures stay on stock levels until you start boosting regularly.
You can expect to hit 100degrees with just a few traffic light launches but this is to be expected - turbo is now pumping 18psi and is both oil and water cooled.

Drivability has been vastly enhanced, even off turbo boost.
The car just seems happier to accelerate.

Also, I've installed a Whiteline 24mm Rear sway bar with stock endlinks.

This involved getting the rear of the car on ramps, and using 12-point triple square bit.
I think they're called xzn spline drivers and you'll need the m6 and m10.

All in all, car now sits flat with absolutely no body roll in regular driving, with very little roll in corners at speeds of 80kmh and less.
Corners that are faster do induce more roll but it is vastly less than stock.

Since the sway bar I have yet to encounter understeer, I have even had the back end step out under hard cornering and braking at Mt Highway.
The car is eager to turn in and you can feel the back of the car lifting and carrying it into corners.
I simply haven't come across a corner I couldn't manage now.
Corner speeds and confidence have drastically improved.
Oem Jetta seats are now an issue as they don't bolster you in enough and I'm being thrown around the car a fair amount.

Next on the table

- the 1K0145803BP intercooler just to help the engine cool charge in upcoming summer.

- Golf Gti dampers and springs to firm up and drop the ride, but maintain oem levels of comfort.

- kumho ku31's, I've had pleasant experience with these tyres in the past and the price is good.

- maybe install golf R valve springs just to be safe when rpms are high.

2014 118 TSi Twincharged Jetta
-GFB DV+
-RNS510
-Underground Performance 18 psi map
-Whiteline 24mm Rear sway bar

Soon: Gti shocks, Audi wheels, short shifter.

[ope126]

Good review mate, keep up the good work!!!

[pocketpunch]

A way overdue update.
Now at 45000kms.
Jetta still going strong, zero issues.
I have had to remove my whiteline swaybar due to some insanely irritating squeaking that started with the bushings.
I feel as if the stock sway bar links don't align the bar correctly so I've taken it off for the time being - back to stock.
I also forgot to set my torque wrench nut on lock so I've actually snapped the triple square bit inside the socket of the sway bar link.
Its tight, but if i remove the link I'll need to replace now anyway.

I'm tempted to sell my RNS510 - no issues with it but tempted to buy the rcd330 to get the app connect feature as I use my phone heavily for media.


Next also will be making a custom intake using a universal pod.
The stock Jetta grilled has a perfect ram scoop for this application.
Cant say it'll help with making power but to hear the turbo spool from inside the cabin will be well worth the adventure.

Sent from my SM-G935F using Tapatalk

[pocketpunch]

Super late update.

80,000 km.

Car still ticking away like a Swiss clock.

No issues with normal maintenance only.

Reinstalled my 24mm RSB from Whiteline but now with adjustable end links.

Once everything was tightened and aligned parallel to the road, no squeaks and annoying noises have been made since.

I've also set the bar in it's "hard" position which makes it act like a 25mm.

Feels tighter again and I really should balance it out with a front away bar now too.

I got my hands on some OEM mk6 GTI springs for pocket change, so I'll be installing those as a temporary solution which I work out my new plans for the car.

I've also dropped in a K&N panel filter which seems to have helped with some of the on and off throttle hesitation this engine can experience with a manual gearbox.

I've got some pretty big plans for this car in the coming months so may start a new thread to discuss with the guys who have already undertaken similar projects.


I guess this rounds up this old thread.

Stage 1 on twin chargers is a must and if you have the later revision engines, it absolutely won't cause any trouble.

Sent from my SM-N950F using Tapatalk