GT4 2.176 Close Ratio 2nd – 6th Gears with Mainshaft Kit

• High grade fine-grained 9310 VAR material Mainshaft
• High grade fine-grained EN36A VAR material Gears
• CNC-machined
• Formula One tooth profile
• Shot-peened
• REM-polished
• Close Ratio Gears optimized for race use

Maximize the performance potential of your Porsche GT4 with our meticulously crafted Close Ratio Mainshaft Kit upgrade. Engineered from high-grade fine-grained 9310 VAR material for the mainshaft and EN36A VAR material for the gears, this kit ensures exceptional strength and durability under the most demanding race conditions.

Precision CNC-machining and Formula One tooth profile design guarantee seamless gear transitions and optimal power delivery. Shot-peened and REM-polished for enhanced surface integrity and reduced friction, our close ratio gears are meticulously optimized for track-focus use, providing you with unrivaled acceleration and responsiveness on the track. Elevate your driving experience to the next level with our Close Ratio Mainshaft Kit upgrade – because every second counts on the raceway.


Gears & Mainshaft Ratios


Mainshaft 17:37 2.176
2nd Gear 17:37 2.176
3rd Gear 19:31 1.632
4th Gear 23:30 1.304
5th Gear 24:26 1.083
6th Gear 26:25 0.962
GT4 2.176 Close Ratio 2nd - 6th Gears with Mainshaft Kit info


Porsche GT4 with manual transmission

Preferred Installer

bill-rader logo

No Politics Racing is happy and very grateful for the collaboration with Mr. Bill Rader at Bill Rader Motorsports, Las Vegas to partner in the development of this product. Mr. Bill Rader is one of the foremost minds in Porsche Racing and transaxle preparation as many know. At NPR we strive to create the highest quality products on the market from the materials used to the knowledge put into every product we manufacture.