Weistec Engineering offers two different turbo upgrades for M157 equipped AMG vehicles, the W.3 Turbos, and the W.4 Turbos. This page will lay out the features and benefits of each upgrade as well as a brief comparison of the two to help you decide which is the better fit for your goals.
The W.3 Turbo Upgrade is based on the OEM GT22 turbos. The turbos are disassembled and several components are machined to accept our CNC Machined Billet Aluminum Compressor wheel. This compressor wheel flows approximately 53+lb/min of air compared to the ~28lb/min that the factory wheel is capable of flowing. The turbos are then balanced and assembled using new seals.
The key benefits of the W.3 Turbos are improved performance, stock like response, and externally they appear to be 100% original turbos. The turbos use the same OEM oil and coolant lines that stock turbos use resulting in a very stealthy installation. Perfect for those that are averse to obvious aftermarket products. Most, if not all, Mercedes technicians would not even notice that the vehicle has W.3 Turbos.
On pump gas, the W.3 Turbos provide improved performance over the factory turbos, generating 660+HP to the wheels on pump gas and as much as 730 HP at the wheels on race gas. They can also be paired with other upgrades we offer, such as our M157 Water/Methanol and ASV System.
There are a few options when it comes to purchasing the W.3 Turbo Upgrade. Since they are based on the OEM turbo, cores are required. Any good set of M157 turbos can be sent directly to us for the upgrade, avoiding a core charge. Some prefer to purchase the W.3 Turbos and pay the refundable core charge with plans to send in their original turbos after install has been completed. Others, who want to hold on to their stock turbos, will purchase a spare set to send in for the upgrade.W.4 Turbos
The W.4 turbos are in an entirely different league than the W.3 turbos or any other turbo upgrade on the market. Weistec spent countless hours designing and testing the W.4 Turbos. No effort was spared in creating the best bolt on turbo upgrade system for the M157 AMG engine. The W.4 turbos completely replace the factory turbos and do so without any core charges or exchange required.
Based on 65lb/min billet wheel ball bearing turbochargers, the W.4 Turbos feature Weistec designed and manufactured cast aluminum compressor covers with 3 inch inlets. On the exhaust side are cast stainless steel turbo-folds which are much larger than the OEM turbo-folds that every other turbo upgrade on the market use. The turbo-folds are the key to unlocking serious top end power. Custom heat wrapped stainless steel braided lines and CNC machined coolant/oil fittings are included with the turbos to ensure no fabrication is needed to install the W.4 Turbos.
Further expanding on the desire to provide a complete package, an entire intake system with carbon fiber air boxes AND our M157 Water/Methanol Injection-ASV system are included with every W.4 Turbocharger System. ECU Tuning is also included, of course.
The factory intake tubes are not directly compatible with the W.4 Turbos. We include the intake system rather than trick customers when it comes to pricing by showing a lower price for the turbos, then requiring the purchase of the intake because the factory intake will not bolt up to the new turbos. The M157 Water/Methanol Injection and ASV System is included because pump gas alone would seriously limit the power potential of the W.4 Turbos. The factory intercooler heat soaks very quickly with high power levels. With the M157 WMI/ASV System, this is not an issue allowing you to enjoy consistent performance with the W.4 Turbos thanks to the reduced intake air temperatures and increased octane benefits.
Other offerings on the market sell just turbos, but require several additional purchases, and custom tuning to be complete, drastically overshooting low advertised pricing. Why buy turbos, an intake system, a methanol injection system, and a tune all separately and from multiple different sources? Then there are also the core charges of several thousand dollars for any turbo upgrade that is based on the OEM turbos. All that to still end up with turbos that are based on the OEM turbo-fold which limits top end performance.
Weistec Engineering offers a complete system, while others simply offer parts
The W.4 Turbos are capable of 1000+HP when running race gas and an engine with upgraded internalsW.3 vs W.4
The W.3 and W.4 Turbos suit different needs. Those that are looking for improved performance but wish to have a stock appearing engine should go with the W.3 turbos. The 100% stock external appearance and compatibility with stock intake and downpipe make the W.3 Turbos the obvious choice for anyone that simply wants more power but not added attention. The W.4 Turbos are for anyone looking for maximum performance without compromise. With the hood open, a W.4 Turbocharger System equipped vehicle can be easily identified thanks to the beautiful carbon fiber air boxes and red intake piping. Subtlety is not a concern when the goal is to have double the power the vehicle came with from the factory.