Kb Performance, 3 5/8 Big Bore Forged Piston Kit. Std
Forged 3-5/8 big bore piston set. Used with 3-5/8" big bore cylinders with 5.330" (stock) to 5.530" (+.200") length. Must use 4-1/4" (stock) (88"); 4-1/2" (93''"); 4-5/8" (96") to 4-3/4" (98") stroker flywheels. 8.50:1 CR with 117cc head; 4.250" stroke & Std. cyl. length. 9.38:1 CR with 117cc head & 4.750" stroke & Std. cyl. length. Piston weight 440gr. Piston pin weight 97gr. Piston pin dia. .791" / offset. Head type: Dome with -42.3cc. Compression height 1.285". Bore 3.625". Stroke 1.250" to 4.750". Rod length 7.440". Cyl. length 5.530" Std to +.200" higher. All KB forged pistons are made from 4032 alloy; a 11% silicon alloy that is formed in a forging press. Forging aluminum gives a superior strength and structural integrity on a molecular level; after which it is fully machined. The combination of this alloy and the forging process allows the piston to flex under detonation; or pre-ignition; giving the best resistance to cracking. Although 4032 has a low expansion rate; it is higher than the cast Hypereutectic. Therefore forged KB pistons will require about .001" wider piston to wall clearance. Pistons are sold as sets; complete with wrist pin retaining rings; wrist pins and piston rings. Please note that all KB forged pistons come equipped with offset wrist pins / piston pins. There is a front and rear section on the piston and it is necessary to install it in the correct way. Please refer to the installation instructions; as provided with each pi
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Compatibility
You can verify compatibility in two ways:
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