Slappy Dunbar. His nickname may sound like a cartoon character, or perhaps the 7th stooge (apparently there were 6 throughout the years). Not exactly the name you would expect to be a heavyweight contender in the Volkswagen/Audi performance turbo aftermarket, but his company, Frankenturbo, is just that. Frankenturbo makes a few variations of their K04 hybrid turbocharger for the 1.8t and 2.7t engines.

The F4 turbo is a direct-fit using the stock downpipe flange and oil/coolant lines. It will also bolt directly up to the stock exhaust manifold, but that is a moot point, considering the basic kit comes with a ceramic-coated high-flow exhaust manifold. A custom turbo inlet pipe, designed to be used with a 3″ MAF housing, is also included in the kit.

The turbo itself is assembled to OEM specifications, by OEM suppliers, using an Inconel 713C alloy turbine wheel, a high-strength 42CrMo alloy shaft, and a 360 alloy thrust bearing. Other features include a ported wastegate chamber and oversized wastegate flap, customizable high-lift wastegate actuator, and a dual-ceramic-coated Si-Mo cast iron turbine housing.

For those looking to get a little more out of their 1.8t than the F4 turbo offers, there is also a F23, designed for the 225 hp Audi TT variant of the 1.8t. This version does not include an exhaust manifold, as it is designed for the high-flow TT225 manifold, as well as the stock TT225 downpipe configuration. In addition to the features of the F4, the F23 also boasts a Al-SiMg aluminum alloy compressor wheel. A MK4 fitment up-pipe adapter is available to make installation into a MK4 Golf/Jetta/Beetle a bolt-on affair. A ceramic-coated tubular TT225 manifold is available for those looking to squeeze out a few extra ponies. Keep in mind that the F23 turbo does make enough power to warrant upgrading the connecting rods.

Frankenturbo’s F4 turbos for the 2.7t engine has all the features of the 1.8t F4 turbo, but also has a compressor made of the same Al-SiMg aluminum alloy featured in the F23 turbo. Also available are optional ceramic-coated tubular high-flow manifolds, and optional aluminum inlet pipes.

All of these turbochargers will work perfectly with Unitronic’s Stage 2+ K04 software or Stage 3 Big Turbo software. These turbo/software upgrades require supporting hardware upgrades, which may include larger injectors, higher-flow fuel pump, larger maf housing, upgraded connecting rods, and exhaust upgrades. Contact us to work out the details of your specific setup.

Contact us if you have any questions regarding Frankenturbo’s product line or pricing.

For more information on Frankenturbo’s line of hybrid turbochargers, check out The Frankenturbo Website

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About Apex Tuning is an independent mechanic shop specializing in Service, Repair, Maintenance, Diagnostics and Performance Tuning for VW and Audi vehicles.  Based in Raleigh, NC we are just a short drive from anywhere in the triangle region.
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