{"title":"Underdrives","description":"","products":[{"product_id":"8-rib-underdrive-pulley","title":"8 RIB UNDERDRIVE PULLEY","description":"Hard Anodized 7\" Billet 8 rib hard anodized 7\" Billet 8 Rib Belt Pulley.  Profiled and milled to go on and off Undrdrive unit without taking off yoke.  Uses ARP Inserts.","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225373909205,"sku":"2700100","price":281.88,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0683\/7400\/3925\/files\/2700100.01-e1518982337248-2.jpg?v=1724981311"},{"product_id":"v-belt-underdrive-pulley","title":"V-BELT UNDERDRIVE PULLEY","description":"HARD ANODIZED 7\" BILLET V-BELT PULLEY. PROFILED AND MILLED TO GO ON AND OFF UNDERDRIVE UNIT WITHOUT TAKING OFF YOKE. USES ARP INSERTS","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225379250389,"sku":"2700200","price":281.88,"currency_code":"USD","in_stock":true}]},{"product_id":"underdrive-1-31","title":"UNDERDRIVE WITH 1.31 RATIO","description":"The Tubeworks Underdrive is a must for off-road truck applications using a Turbo 400 Transmission.  Simply stated, the underdrive increases the RPM of the driveshaft  which allows a ring and pinion ratio to be much higher and stronger.  With 37, 39, or even 42 inch tires, the need for a high final drive number becomes even more important because the  underdrive allows the drivetrain to use as high as a 4.11 Ring and Pinion and have as low as a 5\/83 final drive.   Depending on engine RPM, top speed desired and wheel diameter, we can set you up with the proper planetary ratio and rear end combo for maximum torque or MPH.\u003cbr\u003e\u003cbr\u003eThis unit also allows for a quick interchange of planetary ratios for those competitors that wish to have an extremely low final drive for qualifying. The final drive can change from a 5.43 to a 6.29 or lower in a matter of minutes.\u003cbr\u003e\u003cbr\u003ePictured on the underdrive is the 8-rib pulley that is used for alternator applications.  The pulley is not included in the price of the underdrive and would be an upgrade. 8-rib or v-rib style pulleys are available.\u003cbr\u003e\u003cbr\u003eEach Planetary Underdrive is lubricated and cooled from the transmission.\u003cbr\u003e\u003cstrong\u003eTHE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.31 PLANET SET. (LOWEST RATIO)\u003c\/strong\u003e 1.31 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 4.86 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.11 = 5.38 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.29 = 5.61 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e1.31 X 4.56 = 5.97 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003eT\u003cstrong\u003eHE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.48 PLANET SET. (QUALIFYING RATIO)\u003c\/strong\u003e 1.48 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 5.49 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.11 = 6.08 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.29 = 6.34 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.56 = 6.74 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e(COMPLETE CHART)\u003cbr\u003e1.56 X 3.79 = 5.91\u003cbr\u003e1.56 X 4.11 = 6.41\u003cbr\u003e1.56 X 4.29 = 6.69\u003cbr\u003e1.56 X 4.56 = 7.11\u003cbr\u003e\u003cbr\u003e1.48 X 3.79 = 5.61\u003cbr\u003e1.48 X 4.11 = 6.08\u003cbr\u003e1.48 X 4.29 = 6.35\u003cbr\u003e1.48 X 4.56 = 6.75\u003cbr\u003e\u003cbr\u003e1.41 X 3.79 = 5.34\u003cbr\u003e1.41 X 4.11 = 5.80\u003cbr\u003e1.41 X 4.29 = 6.05\u003cbr\u003e1.41 X 4.56 = 6.43\u003cbr\u003e\u003cbr\u003e1.37 X 3.79 = 5.19\u003cbr\u003e1.37 X 4.11 = 5.63\u003cbr\u003e1.37 X 4.29 = 5.88\u003cbr\u003e1.37 X 4.56 = 6.25\u003cbr\u003e\u003cbr\u003e1.34 X 3.79 = 5.08\u003cbr\u003e1.34 X 4.11 = 5.51\u003cbr\u003e1.34 X 4.29 = 5.75\u003cbr\u003e1.34 X 4.56 = 6.11\u003cbr\u003e\u003cbr\u003e1.31 X 3.79 = 4.96\u003cbr\u003e1.31 X 4.11 = 5.38\u003cbr\u003e1.31 X 4.29 = 5.62\u003cbr\u003e1.31 X 4.56 = 5.97\u003cbr\u003e\u003cbr\u003e","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225383805141,"sku":"2800131","price":8356.37,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0683\/7400\/3925\/files\/2840034.04-e1516584647832-1.jpg?v=1724981331"},{"product_id":"t400-output-shafts","title":"T400 OUTPUT SHAFTS","description":"Transmission output shaft with our 300m Billet input shaft.  This Combination is required when installing a Tubeworks Underdrive System on a Turbo 400 Transmission.","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225386688725,"sku":"2801100","price":1230.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0683\/7400\/3925\/files\/2840100.01-e1516252026771-2.jpg?v=1724981343"},{"product_id":"mounting-plate","title":"MOUNTING PLATE","description":"Mounting Plate 1","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225389605077,"sku":"","price":937.88,"currency_code":"USD","in_stock":true}]},{"product_id":"underdrive-1-34","title":"UNDERDRIVE WITH 1.34 RATIO","description":"THE TUBEWORKS UNDERDRIVE IS A MUST FOR PROFESSIONAL OFF-ROAD TRUCKS. USING A TURBO 400 TRANSMISSION, THE UNDERDRIVE DECREASES THE RPM OF THE DRIVESHAFT WHICH ALLOWS THE RING AND PINION RATIO TO BE MUCH LOWER AND STRONGER. WHEN USING 37\", 39\", OR EVEN 42\" TIRES, THE NEED FOR A HIGH FINAL DRIVE NUMBER IS CRUCIAL. THE UNDERDRIVE ALLOWS THE DRIVETRAIN TO USE A LOW RATIO SUCH AS A 4.11 RING AND PINION, AND CORRECTS IT TO A FINAL DRIVE RATIO SUCH AS A 5:83. DEPENDING ON MOTOR COMBINATION (AS WELL AS TOP SPEED PREFERENCE AND WHEEL SIZE) WE CAN SET YOU UP WITH THE PROPER PLANETARY RATIO AND REAR END COMBO FOR MAXIMUM TORQUE OR MPH.\u003cbr\u003e\u003cbr\u003eTHIS UNIT WILL ALSO ALLOW A QUICK INTERCHANGE OF PLANETARY RATIOS FOR THOSE COMPETITORS THAT WISH TO HAVE A NUMERICALLY HIGH FINAL DRIVE RATIO FOR QUALIFYING SCENARIOS. IN A MATTER OF MINUTES THE FINAL DRIVE CAN GO FROM 5.43 TO 6.29 OR LOWER.\u003cbr\u003e\u003cbr\u003ePICTURED ON THIS UNDERDRIVE IS THE 8-RIB PULLEY THAT IS USED FOR ALTERNATOR APPLICATIONS.\u003cstrong\u003e[\u003c\/strong\u003e\u003cstrong\u003e\u003cem\u003ePULLEY IS AN UPGRADE AND IS NOT INCLUDED IN PRICING.\u003c\/em\u003e 8-RIB OR V-RIB STYLE PULLEYS ARE AVAILABLE.]\u003c\/strong\u003e EACH PLANETARY UNDERDRIVE IS LUBRICATED AND COOLED FROM THE TRANSMISSION.\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[THE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.31 PLANET SET. (LOWEST RATIO)]\u003c\/strong\u003e 1.31 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 4.86 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.11 = 5.38 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.29 = 5.61 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e1.31 X 4.56 = 5.97 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[\u003c\/strong\u003e T\u003cstrong\u003eHE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.48 PLANET SET. (QUALIFYING RATIO)]\u003c\/strong\u003e 1.48 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 5.49 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.11 = 6.08 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.29 = 6.34 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.56 = 6.74 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[COMPLETE CHART]\u003c\/strong\u003e 1.56 X 3.79 = 5.91\u003cbr\u003e1.56 X 4.11 = 6.41\u003cbr\u003e1.56 X 4.29 = 6.69\u003cbr\u003e1.56 X 4.56 = 7.11\u003cbr\u003e\u003cbr\u003e1.48 X 3.79 = 5.61\u003cbr\u003e1.48 X 4.11 = 6.08\u003cbr\u003e1.48 X 4.29 = 6.35\u003cbr\u003e1.48 X 4.56 = 6.75\u003cbr\u003e\u003cbr\u003e1.41 X 3.79 = 5.34\u003cbr\u003e1.41 X 4.11 = 5.80\u003cbr\u003e1.41 X 4.29 = 6.05\u003cbr\u003e1.41 X 4.56 = 6.43\u003cbr\u003e\u003cbr\u003e1.37 X 3.79 = 5.19\u003cbr\u003e1.37 X 4.11 = 5.63\u003cbr\u003e1.37 X 4.29 = 5.88\u003cbr\u003e1.37 X 4.56 = 6.25\u003cbr\u003e\u003cbr\u003e1.34 X 3.79 = 5.08\u003cbr\u003e1.34 X 4.11 = 5.51\u003cbr\u003e1.34 X 4.29 = 5.75\u003cbr\u003e1.34 X 4.56 = 6.11\u003cbr\u003e\u003cbr\u003e1.31 X 3.79 = 4.96\u003cbr\u003e1.31 X 4.11 = 5.38\u003cbr\u003e1.31 X 4.29 = 5.62\u003cbr\u003e1.31 X 4.56 = 5.97\u003cbr\u003e\u003cbr\u003e","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225414738133,"sku":"2800134","price":8169.25,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0683\/7400\/3925\/files\/TW_Underdrive1.jpg?v=1724981444"},{"product_id":"underdrive-1-37","title":"UNDERDRIVE WITH 1.37 RATIO","description":"THE TUBEWORKS UNDERDRIVE IS A MUST FOR PROFESSIONAL OFF-ROAD TRUCKS. USING A TURBO 400 TRANSMISSION, THE UNDERDRIVE DECREASES THE RPM OF THE DRIVESHAFT WHICH ALLOWS THE RING AND PINION RATIO TO BE MUCH LOWER AND STRONGER. WHEN USING 37\", 39\", OR EVEN 42\" TIRES, THE NEED FOR A HIGH FINAL DRIVE NUMBER IS CRUCIAL. THE UNDERDRIVE ALLOWS THE DRIVETRAIN TO USE A LOW RATIO SUCH AS A 4.11 RING AND PINION, AND CORRECTS IT TO A FINAL DRIVE RATIO SUCH AS A 5:83. DEPENDING ON MOTOR COMBINATION (AS WELL AS TOP SPEED PREFERENCE AND WHEEL SIZE) WE CAN SET YOU UP WITH THE PROPER PLANETARY RATIO AND REAR END COMBO FOR MAXIMUM TORQUE OR MPH.\u003cbr\u003e\u003cbr\u003eTHIS UNIT WILL ALSO ALLOW A QUICK INTERCHANGE OF PLANETARY RATIOS FOR THOSE COMPETITORS THAT WISH TO HAVE A NUMERICALLY HIGH FINAL DRIVE RATIO FOR QUALIFYING SCENARIOS. IN A MATTER OF MINUTES THE FINAL DRIVE CAN GO FROM 5.43 TO 6.29 OR LOWER.\u003cbr\u003e\u003cbr\u003ePICTURED ON THIS UNDERDRIVE IS THE 8-RIB PULLEY THAT IS USED FOR ALTERNATOR APPLICATIONS.\u003cstrong\u003e[\u003c\/strong\u003e\u003cstrong\u003e\u003cem\u003ePULLEY IS AN UPGRADE AND IS NOT INCLUDED IN PRICING.\u003c\/em\u003e 8-RIB OR V-RIB STYLE PULLEYS ARE AVAILABLE.]\u003c\/strong\u003e EACH PLANETARY UNDERDRIVE IS LUBRICATED AND COOLED FROM THE TRANSMISSION.\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[THE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.31 PLANET SET. (LOWEST RATIO)]\u003c\/strong\u003e 1.31 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 4.86 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.11 = 5.38 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.29 = 5.61 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e1.31 X 4.56 = 5.97 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[\u003c\/strong\u003e T\u003cstrong\u003eHE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.48 PLANET SET. (QUALIFYING RATIO)]\u003c\/strong\u003e 1.48 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 5.49 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.11 = 6.08 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.29 = 6.34 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.56 = 6.74 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[COMPLETE CHART]\u003c\/strong\u003e 1.56 X 3.79 = 5.91\u003cbr\u003e1.56 X 4.11 = 6.41\u003cbr\u003e1.56 X 4.29 = 6.69\u003cbr\u003e1.56 X 4.56 = 7.11\u003cbr\u003e\u003cbr\u003e1.48 X 3.79 = 5.61\u003cbr\u003e1.48 X 4.11 = 6.08\u003cbr\u003e1.48 X 4.29 = 6.35\u003cbr\u003e1.48 X 4.56 = 6.75\u003cbr\u003e\u003cbr\u003e1.41 X 3.79 = 5.34\u003cbr\u003e1.41 X 4.11 = 5.80\u003cbr\u003e1.41 X 4.29 = 6.05\u003cbr\u003e1.41 X 4.56 = 6.43\u003cbr\u003e\u003cbr\u003e1.37 X 3.79 = 5.19\u003cbr\u003e1.37 X 4.11 = 5.63\u003cbr\u003e1.37 X 4.29 = 5.88\u003cbr\u003e1.37 X 4.56 = 6.25\u003cbr\u003e\u003cbr\u003e1.34 X 3.79 = 5.08\u003cbr\u003e1.34 X 4.11 = 5.51\u003cbr\u003e1.34 X 4.29 = 5.75\u003cbr\u003e1.34 X 4.56 = 6.11\u003cbr\u003e\u003cbr\u003e1.31 X 3.79 = 4.96\u003cbr\u003e1.31 X 4.11 = 5.38\u003cbr\u003e1.31 X 4.29 = 5.62\u003cbr\u003e1.31 X 4.56 = 5.97\u003cbr\u003e\u003cbr\u003e","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225420210389,"sku":"2800137","price":8562.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0683\/7400\/3925\/files\/2840034.04-e1516584647832-1_9dcaa681-06f6-4287-8978-3b7259327aaa.jpg?v=1724981456"},{"product_id":"underdrive-1-41","title":"UNDERDRIVE WITH 1.41 RATIO","description":"THE TUBEWORKS UNDERDRIVE IS A MUST FOR PROFESSIONAL OFF-ROAD TRUCKS. USING A TURBO 400 TRANSMISSION, THE UNDERDRIVE DECREASES THE RPM OF THE DRIVESHAFT WHICH ALLOWS THE RING AND PINION RATIO TO BE MUCH LOWER AND STRONGER. WHEN USING 37\", 39\", OR EVEN 42\" TIRES, THE NEED FOR A HIGH FINAL DRIVE NUMBER IS CRUCIAL. THE UNDERDRIVE ALLOWS THE DRIVETRAIN TO USE A LOW RATIO SUCH AS A 4.11 RING AND PINION, AND CORRECTS IT TO A FINAL DRIVE RATIO SUCH AS A 5:83. DEPENDING ON MOTOR COMBINATION (AS WELL AS TOP SPEED PREFERENCE AND WHEEL SIZE) WE CAN SET YOU UP WITH THE PROPER PLANETARY RATIO AND REAR END COMBO FOR MAXIMUM TORQUE OR MPH.\u003cbr\u003e\u003cbr\u003eTHIS UNIT WILL ALSO ALLOW A QUICK INTERCHANGE OF PLANETARY RATIOS FOR THOSE COMPETITORS THAT WISH TO HAVE A NUMERICALLY HIGH FINAL DRIVE RATIO FOR QUALIFYING SCENARIOS. IN A MATTER OF MINUTES THE FINAL DRIVE CAN GO FROM 5.43 TO 6.29 OR LOWER.\u003cbr\u003e\u003cbr\u003ePICTURED ON THIS UNDERDRIVE IS THE 8-RIB PULLEY THAT IS USED FOR ALTERNATOR APPLICATIONS.\u003cstrong\u003e[\u003c\/strong\u003e\u003cstrong\u003e\u003cem\u003ePULLEY IS AN UPGRADE AND IS NOT INCLUDED IN PRICING.\u003c\/em\u003e 8-RIB OR V-RIB STYLE PULLEYS ARE AVAILABLE.]\u003c\/strong\u003e EACH PLANETARY UNDERDRIVE IS LUBRICATED AND COOLED FROM THE TRANSMISSION.\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[THE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.31 PLANET SET. (LOWEST RATIO)]\u003c\/strong\u003e 1.31 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 4.86 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.11 = 5.38 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.29 = 5.61 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e1.31 X 4.56 = 5.97 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[\u003c\/strong\u003e T\u003cstrong\u003eHE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.48 PLANET SET. (QUALIFYING RATIO)]\u003c\/strong\u003e 1.48 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 5.49 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.11 = 6.08 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.29 = 6.34 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.56 = 6.74 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[COMPLETE CHART]\u003c\/strong\u003e 1.56 X 3.79 = 5.91\u003cbr\u003e1.56 X 4.11 = 6.41\u003cbr\u003e1.56 X 4.29 = 6.69\u003cbr\u003e1.56 X 4.56 = 7.11\u003cbr\u003e\u003cbr\u003e1.48 X 3.79 = 5.61\u003cbr\u003e1.48 X 4.11 = 6.08\u003cbr\u003e1.48 X 4.29 = 6.35\u003cbr\u003e1.48 X 4.56 = 6.75\u003cbr\u003e\u003cbr\u003e1.41 X 3.79 = 5.34\u003cbr\u003e1.41 X 4.11 = 5.80\u003cbr\u003e1.41 X 4.29 = 6.05\u003cbr\u003e1.41 X 4.56 = 6.43\u003cbr\u003e\u003cbr\u003e1.37 X 3.79 = 5.19\u003cbr\u003e1.37 X 4.11 = 5.63\u003cbr\u003e1.37 X 4.29 = 5.88\u003cbr\u003e1.37 X 4.56 = 6.25\u003cbr\u003e\u003cbr\u003e1.34 X 3.79 = 5.08\u003cbr\u003e1.34 X 4.11 = 5.51\u003cbr\u003e1.34 X 4.29 = 5.75\u003cbr\u003e1.34 X 4.56 = 6.11\u003cbr\u003e\u003cbr\u003e1.31 X 3.79 = 4.96\u003cbr\u003e1.31 X 4.11 = 5.38\u003cbr\u003e1.31 X 4.29 = 5.62\u003cbr\u003e1.31 X 4.56 = 5.97\u003cbr\u003e\u003cbr\u003e","brand":"Tubeworks","offers":[{"title":"Default Title","offer_id":49225423552725,"sku":"2800141","price":8169.25,"currency_code":"USD","in_stock":true}]},{"product_id":"underdrive-1-48","title":"UNDERDRIVE WITH 1.48 RATIO (QUALIFYING RATIO)","description":"THE TUBEWORKS UNDERDRIVE IS A MUST FOR PROFESSIONAL OFF-ROAD TRUCKS. USING A TURBO 400 TRANSMISSION, THE UNDERDRIVE DECREASES THE RPM OF THE DRIVESHAFT WHICH ALLOWS THE RING AND PINION RATIO TO BE MUCH LOWER AND STRONGER. WHEN USING 37\", 39\", OR EVEN 42\" TIRES, THE NEED FOR A HIGH FINAL DRIVE NUMBER IS CRUCIAL. THE UNDERDRIVE ALLOWS THE DRIVETRAIN TO USE A LOW RATIO SUCH AS A 4.11 RING AND PINION, AND CORRECTS IT TO A FINAL DRIVE RATIO SUCH AS A 5:83. DEPENDING ON MOTOR COMBINATION (AS WELL AS TOP SPEED PREFERENCE AND WHEEL SIZE) WE CAN SET YOU UP WITH THE PROPER PLANETARY RATIO AND REAR END COMBO FOR MAXIMUM TORQUE OR MPH.\u003cbr\u003e\u003cbr\u003eTHIS UNIT WILL ALSO ALLOW A QUICK INTERCHANGE OF PLANETARY RATIOS FOR THOSE COMPETITORS THAT WISH TO HAVE A NUMERICALLY HIGH FINAL DRIVE RATIO FOR QUALIFYING SCENARIOS. IN A MATTER OF MINUTES THE FINAL DRIVE CAN GO FROM 5.43 TO 6.29 OR LOWER.\u003cbr\u003e\u003cbr\u003ePICTURED ON THIS UNDERDRIVE IS THE 8-RIB PULLEY THAT IS USED FOR ALTERNATOR APPLICATIONS.\u003cstrong\u003e[\u003c\/strong\u003e\u003cstrong\u003e\u003cem\u003ePULLEY IS AN UPGRADE AND IS NOT INCLUDED IN PRICING.\u003c\/em\u003e 8-RIB OR V-RIB STYLE PULLEYS ARE AVAILABLE.]\u003c\/strong\u003e EACH PLANETARY UNDERDRIVE IS LUBRICATED AND COOLED FROM THE TRANSMISSION.\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[THE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.31 PLANET SET. (LOWEST RATIO)]\u003c\/strong\u003e 1.31 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 4.86 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.11 = 5.38 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.31 X 4.29 = 5.61 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e1.31 X 4.56 = 5.97 (FINAL DRIVE)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[\u003c\/strong\u003e T\u003cstrong\u003eHE MATH TO DETERMINE FINAL DRIVE IS AS FOLLOWS USING A 1.48 PLANET SET. (QUALIFYING RATIO)]\u003c\/strong\u003e 1.48 (PLANET RATIO) X 3.71 (R\u0026amp;P RATIO) = 5.49 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.11 = 6.08 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.29 = 6.34 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e1.48 X 4.56 = 6.74 (FINAL DRIVE RATIO)\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cbr\u003e\u003cstrong\u003e[COMPLETE CHART]\u003c\/strong\u003e 1.56 X 3.79 = 5.91\u003cbr\u003e1.56 X 4.11 = 6.41\u003cbr\u003e1.56 X 4.29 = 6.69\u003cbr\u003e1.56 X 4.56 = 7.11\u003cbr\u003e\u003cbr\u003e1.48 X 3.79 = 5.61\u003cbr\u003e1.48 X 4.11 = 6.08\u003cbr\u003e1.48 X 4.29 = 6.35\u003cbr\u003e1.48 X 4.56 = 6.75\u003cbr\u003e\u003cbr\u003e1.41 X 3.79 = 5.34\u003cbr\u003e1.41 X 4.11 = 5.80\u003cbr\u003e1.41 X 4.29 = 6.05\u003cbr\u003e1.41 X 4.56 = 6.43\u003cbr\u003e\u003cbr\u003e1.37 X 3.79 = 5.19\u003cbr\u003e1.37 X 4.11 = 5.63\u003cbr\u003e1.37 X 4.29 = 5.88\u003cbr\u003e1.37 X 4.56 = 6.25\u003cbr\u003e\u003cbr\u003e1.34 X 3.79 = 5.08\u003cbr\u003e1.34 X 4.11 = 5.51\u003cbr\u003e1.34 X 4.29 = 5.75\u003cbr\u003e1.34 X 4.56 = 6.11\u003cbr\u003e\u003cbr\u003e1.31 X 3.79 = 4.96\u003cbr\u003e1.31 X 4.11 = 5.38\u003cbr\u003e1.31 X 4.29 = 5.62\u003cbr\u003e1.31 X 4.56 = 5.97\u003cbr\u003e\u003cbr\u003e","brand":"Tubeworks","offers":[{"title":"1.54 \/ 1.54","offer_id":51402453385429,"sku":"2800148","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.54 \/ 1.48","offer_id":51402453418197,"sku":"2800149","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.54 \/ 1.46","offer_id":51402453450965,"sku":"2800150","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.48 \/ 1.54","offer_id":51402453483733,"sku":"2800151","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.48 \/ 1.48","offer_id":51402453516501,"sku":"2800152","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.48 \/ 1.46","offer_id":51402453549269,"sku":"2800153","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.46 \/ 1.54","offer_id":51402453582037,"sku":"2800154","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.46 \/ 1.48","offer_id":51402453614805,"sku":"2800155","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.46 \/ 1.46","offer_id":51402453647573,"sku":"2800156","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.44 \/ 1.54","offer_id":51402453680341,"sku":"2800157","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.44 \/ 1.48","offer_id":51402453713109,"sku":"2800158","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.44 \/ 1.46","offer_id":51402453745877,"sku":"2800159","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.41 \/ 1.54","offer_id":51402453778645,"sku":"2800160","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.41 \/ 1.48","offer_id":51402453811413,"sku":"2800161","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.41 \/ 1.46","offer_id":51402453844181,"sku":"2800162","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.37 \/ 1.54","offer_id":51402453876949,"sku":"2800163","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.37 \/ 1.48","offer_id":51402453909717,"sku":"2800164","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.37 \/ 1.46","offer_id":51402453942485,"sku":"2800165","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.34 \/ 1.54","offer_id":51402453975253,"sku":"2800166","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.34 \/ 1.48","offer_id":51402454008021,"sku":"2800167","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.34 \/ 1.46","offer_id":51402454040789,"sku":"2800168","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.31 \/ 1.54","offer_id":51402454073557,"sku":"2800169","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.31 \/ 1.48","offer_id":51402454106325,"sku":"2800170","price":8958.5,"currency_code":"USD","in_stock":true},{"title":"1.31 \/ 1.46","offer_id":51402454139093,"sku":"2800171","price":8958.5,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0683\/7400\/3925\/files\/TW_Underdrive1_76963db1-4cad-495b-8a68-752a89201233.jpg?v=1745286732"}],"url":"https:\/\/tubeworks.com\/collections\/underdrives.oembed","provider":"Tubeworks","version":"1.0","type":"link"}