We've been seeing quite a few MQB custom tune customers with suboptimal supporting flow mods for their Vortex and similar bolt-on turbos. We usually notice restriction issues within the first couple revisions and try to help consult on the setup.
More often than not, the main issue is the intake and turbo inlet setup. Most aftermarket TIP's (turbo inlet pipes) are sized for the stock IS38 turbo and are too small for these upgraded bolt-on turbos. The smaller inlet diameter and restrictive intake setups cause a major issue when we try to turn up the boost.
As an example, here is a car I'm working on running our Vortex XL turbo. As we turned up the boost to a target of 31psi, I noticed that at higher RPM, the wastegate was hitting 93% while the turbo was struggling to make only 29psi. You can see this in the log snapshot here:
![May be an image of text that says '2D arameters Template Custom Time XAxis 35 二 100 3U YANis1 EngineSpeed|RPH] RPM] AmbientA YAuis2 Temp| (F) a 06 Relstire elalireMaridld lariald Pressure DSi 08 YANie3V TutineAct. TutineAcl.FralVake1 FinalYakue1%) AmbientA Air Temp. F|& Relative Manifold Pressure (psi) Turbine Act. Final Value 2.800 3,000 %)v Engine Speed (RPM) 3.200 3,400 3,600 3,800 4,000 4,200 4,400 4.600 4,800 5,000 5.200 5,400 5.600 5,800 6,000 6.200 6,400 6,600 6.800 7,000 7,200'](https://scontent-sjc3-1.xx.fbcdn.net/v/t39.30808-6/486633999_9856483004402696_8183570949825734595_n.jpg?_nc_cat=108&ccb=1-7&_nc_sid=127cfc&_nc_ohc=n5Wde8_axLcQ7kNvgHsODG3&_nc_oc=AdkR-lf7pqUNhuIuHzmZmJayHDhuJeY_h593AOWCRci3-FdFRLJ-wpsKt3LQc_-FyWs&_nc_zt=23&_nc_ht=scontent-sjc3-1.xx&_nc_gid=R9wNM2pZsDvxHXoO3xdwtQ&oh=00_AYFtpHNKwU8J6ou1JLdnkhZRQgYOPtnE62J3UYmXNLVvTQ&oe=67EA6883)
More often than not, the main issue is the intake and turbo inlet setup. Most aftermarket TIP's (turbo inlet pipes) are sized for the stock IS38 turbo and are too small for these upgraded bolt-on turbos. The smaller inlet diameter and restrictive intake setups cause a major issue when we try to turn up the boost.
As an example, here is a car I'm working on running our Vortex XL turbo. As we turned up the boost to a target of 31psi, I noticed that at higher RPM, the wastegate was hitting 93% while the turbo was struggling to make only 29psi. You can see this in the log snapshot here:
I went over the customer's setup and noticed he was running the Unitronic carbon cold air intake with the unitronic TIP. While this intake system works well for the stock IS20 and IS38 turbos, it is not a good fit for larger turbos like the Vortex XL. I recommended several upgrade options to the customer. He could try to upgrade just the inlet pipe with one of the larger inlets that are sized appropriately (MST or DBV2), or he could upgrade the entire intake system with the Blaze Atom V2 which comes with an integrated inlet flange that is sized correctly for the larger turbo. The customer decided to go with the Blaze Intake to get a complete integrated system that has been proven to work.
After installing the Blaze intake/inlet, the customer took another log on the same tune file to see how things changed. With nothing else changed, the car is now easily making over 31psi with 78% wastegate. So we now gained 2psi of boost and reduced wastegate by 15%, giving us headroom to turn things up further. We also noticed a 100-200RPM improvement in spool. You can see the results in this snapshot:
![May be an image of text that says '2D Parameters Template Custom Time እዞራች Speed (RPM] YANs1 7264 100 10 O5 30 90 AmtientAj Temp (F1 | Relalive elaliveMarioldPressun Mariold Pressure 48 YAnis3V 80 AmbientA Air Temp, FI8 Relative Manifold Pressure () 31.5 Final ValJe 10 Turbine Act, Final a|Value 2,800 3,000 3,200 3,400 %)vs Engine Speed Speed(RPM) ) 3,600 3,800 4,000 4,200 4.400 4,600 4,800 5.000 5,200 5,400 5,600 5,800 6.000 6,200 6,400 6,600 6,800 7.000 7,200 7.400'](https://scontent-sjc3-1.xx.fbcdn.net/v/t39.30808-6/486436498_9856512957733034_2937975877672249960_n.jpg?_nc_cat=105&ccb=1-7&_nc_sid=127cfc&_nc_ohc=IdIAPHlll10Q7kNvgEv5AvV&_nc_oc=Adkic5Y7wmHLeMFuq1dmzKqpwsOMuCNjWlW_HOQkpEfkp5GLMk62-IcyLR54LS5ntmM&_nc_zt=23&_nc_ht=scontent-sjc3-1.xx&_nc_gid=rCpN08Dw8hjKEp4lgbmWEQ&oh=00_AYGdaq7yFVljY_NGlrRoGmNACZLrEkfE3Ete1eFJt8q8xQ&oe=67EA5F15)
After installing the Blaze intake/inlet, the customer took another log on the same tune file to see how things changed. With nothing else changed, the car is now easily making over 31psi with 78% wastegate. So we now gained 2psi of boost and reduced wastegate by 15%, giving us headroom to turn things up further. We also noticed a 100-200RPM improvement in spool. You can see the results in this snapshot:
Please note that conditions for these tests were very similar. The original test with the unitronic intake was actually done in 2F colder weather, so if anything, it had a slight advantage.
We urge our customers to use appropriate supporting mods when upgrading their turbos, and ideally before starting their custom tunes. Please always feel free to reach out to our sales and support staff for parts recommendations.
We urge our customers to use appropriate supporting mods when upgrading their turbos, and ideally before starting their custom tunes. Please always feel free to reach out to our sales and support staff for parts recommendations.