250R Transmission

    The 250R motor, while exceptionally strong and known to be very reliable, does have a weak point when the power output levels are increased.  The transmission is that weak point.  The transmission gears are made of a cast iron alloy that works well with stock power output levels.  Once the power output level is increased the longevity and integrity of the transmission comes into question.  Known trouble spots such as the 2nd gear countershaft gear have been addressed in years past simply by replacing the gear and nothing else. 

    Patriot Racing has found what to date has been the best and most reliable and very importantly repeatable method for ensuring maximum transmission life and strength.  By using state of the art cryogenic tempering processes the weaker cast iron alloy transforms into a denser and much stronger material.  The hardness of the material remains unchanged, just the crystal structure of the material changes from a weak porous one to a denser, stronger structure. 

    The transmission stacks are disassembled and thoroughly cleaned and inspected.  The transmission is precision measured  to ensure compliance with all factory tolerances.  The transmission is then gone over and all sharp edges are broken and all burrs from the gear face, cut-outs, and teeth are removed.  This process while time consuming, removes stress riser points from the gears.  Once completed the transmission is cleaned again and reassembled.  After that it is cryogenically tempered following all industry standards and specifications.

    Your transmission is then returned ready to run.  There is no further process necessary.  The cryogenic tempering process has proven itself to be the best cure for maximizing transmission life and strength. 

Please note all machine work to the transmission i.e. over-ride cut , should be performed prior to the cryogenic process.

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