K04 Turbo Upgrade Notes


K04: Stage 3 Turbo Upgrade Setup Notes for Skoda Laura TSI

Even though APR states that the turbo kit is more or less plug and play, with all bits included in the kit, there are a few more items that as per me are an absolute necessity for the car to perform.

– Upgraded Diverter Valve (DV): You have the choice of a BOV (Best ones are Forge and CTS Turbo) or a GFB DV+ which removes the weak parts of the stock dv and replaced them with stronger parts. I went with the DV+ because it helps throttle response as it retains the factory solenoid and improves low-end, while holding boost as good as a mechanical BOV.

– Spark Plugs: THE CORRECT ONES gapped correctly too. APR originally sent me the NGK (2667) BKR7EIX Iridium IX Spark Plug gapped at 0.031″, which are meant for the TT. The car faced a lot of misfire issues with the car at lower rpms and it affected the boost response. The low-end of the car was terrible also there was timing pull in the higher rev range. After speaking to a few tuner friends from the US, I moved to the BKR8EIX Iridium (2668), gapped at 0.032 from the factory, re-gapped to 0.024”. That solved my low-end misfires and cleaned up my top end pull.

– Cat-Less or High Flow Cat Downpipe and Full Exhaust: let’s face it, you’re going about putting a bigass turbo on a 1.8L engine, so no point choking it with CATS and Resonators. You NEED a free flowing exhaust to get the full potential of the turbo. I know of people running this setup with the stock exhaust, but that’s plain STUPID in my opinion. With stock exhaust u end up making the car nearly undriveable with huge turbo lag and a non-existent top end.

– Upgraded Coilpacks: The APR kit came with optional TT coilpacks(INR 25k) which are supposed to be better. My OEM’s had just 12k on them and had no issues, but we swapped them out regardless. I was having constant misfire issues with these. So I got the R8 coilpacks from the Audi dealership (~3.4k INR each). Sorted all the misfires out and the car purrs like a cat. A cat with a big ass turbo.

– 3Bar Map Sensor (Bosche from the Golf R or S3): All tunes available for the K04 Kits support the existing 2.5BAR Bosche MAP sensor that exists on the 1.8TSI. But I faced issues with the senor as the boost was building up too fast and overshooting the sensor’s limits and putting the car into limp mode. Pete’s tunes this out with their map so you can retain the 2.5Bar sensor. APR replaces the sensor with a 3Bar unit from the Audi S3/Golf R and provides a separate map for it. This map makes MORE power than the 2.5Bar Map as the boost threshold is increased and the boost resolution is better. Now other tuners get power levels of up to 320hp with the 2.5Bar while the APR with the 3Bar gets u ~338hp! if you’re going with an APR kit, I’d highly recommend you replace the Sensor with a 3Bar one and ask APR to provide you with the 3Bar sensor map. Also note, this is NOT a plug and play device. Make sure u have the map for it or your car will not perform.

– High Flow Turbo Outlet Pipe (specifically for K04 TSI turbo): The pipe from the Turbo outlet to the intercooler coupler. This is the best mod you can do for the K04, as it replaces the restrictive pancake pipe with one that has a lot more volume. This relieves stress on the turbo, allows it to spool faster and make better peak boost. For the pipe vendors, avoid Neuspeed as they have fitment issues with the APR kit. I’d go for Spullen, as their fitment is spot on and they sell the Pipe as a Kit with the throttle pipe as well.

– Throttle Body Pipe (same for K04 and K03 (stock turbo), but make sure it’s for the EA888 Mk2 engine and not the MK3): Again this hugely helps throttle response while removing restrictions from the pipes and adds volume to cater for the significant increase in boost from the K04 turbo.

– Intake Kit: Several out there, APR/Spullen/CTS Turbo/VW Racing etc. Choose one with a closed enclosure for the filter so that it doesn’t suck in the hot engine bay air. Even though there are people running it with the OEM intake, the flow of the OEM intake just get choked when the turbo hits boost.

– Clutch: The stock clutch will take the power for some time unless you’re constantly launching the car and being very aggressive on the shifts and repeated high rpm pulls. Ideally it a good idea to get a n upgraded clutch and you will need it in about 10-15k kms. But if you have to, the stock clutch does hold well till the time to upgrade arrives. I cooked my clutch in under 8000kms and upgraded to a Spec Stage 3+ Clutch kit that comes with a semi-metallic sprung disc and a single mass lightened flywheel. Feels nearly as good as stock and is rated to 400lbft of torque. This also didn’t last for more than 3000kms of hard driving. So I switched to the Spec Stag 5 clutch.

– Upgraded Clutch Slave Cylinder without the Clutch Delay Valve

– Intercooler(IC): The Stock IC will NOT suffice the K04. Whoever said it would has never driven a big turbo car in India. The IC heat soaks so easy and the small core of the stock will choke the top end. The sheer volume of airflow from the K04 overwhelms the IC and chokes the engine up with hot air. There are a few options out there for larger core. There are intercoolers available from APR, Integrated Engineering, Wagner Tuning, Neuspeed Intercooler and a few others. All work more or less same replacing the OEM core sandwiched between the Radiator and the Condenser except for the Neuspeed which is a proper FMIC, albeit with less volume than the rest. I ran the car with the OEM intercooler for 6 months and I just kept seeing the IATs shoot up to 70 degrees causing the car to pull timing.
Eventually I got the Integrated Engineering Intercooler and not only were IATs down and consistent to around 10-15 degrees over ambient, it gave me a power bump to 355hp and 499NM Torque!

– Dogbone mount: this was recommended to me by Pete’s to help reduce torque steer and wheel hop that’s associated with most high HP VAG cars. And boy does it make a huge difference. Car feels planted, power delivery is much more consistent in lower gears, and the wheel hop is gone. I can go full throttle much faster and put the power down to the ground better and steering feel improves as well. I cannot emphasise how much better this will make your car feel. It adds a bit more NVH at idle but I’ve noticed it only when the A/C is on.

– Brakes: I cannot emphasize more on this part. YOU WILL NEED A BIG BRAKE KIT if you intend to survive the K04. There are several brake disc/brake pad upgrades in the market but the stock brake setup (discs n callipers) are just not enough stopping power for the K04. There are several options out there now. Tarox 320mm-340mm 6Pot/8Pot setup, Brembo 320mm 4pot setup, and the D2 Racing 340mm 8Pot setup. Pick your poison. You are going to need it.

– Suspension: Let’s face it, your building a car with over 300 horsepower, it’d be suicidal to run it on the stock suspension. Ideally you should move to a Coilover kit, but if budget is a constraint, get some stiffer springs and B6 shocks. It will not only help you put the power down to the ground, but also help braking and overall handling. I already had the Bilstien B14 coilovers. Best option is a damping adjustable coilover like Bilstien B16 and KW V1/V2/Street Comfort, that allows you to dial in the front damping to get the best traction off the line and in corners.

– Tires: Let’s face it, the stock 195 tires were pathetic at handling the stock 160 horses of the car, let alone 210 horses of stage 2, do you really think its going to take the 300+horses of the K04. Ideally you should get 245 section tires to put the power down properly, BUT 225 section with GOOD tires also gets the job done to a certain extent without braking the bank.