{"product_id":"hot-saw-pop-up-piston-compatible-with-husqvarna-371-372-non-x-torq-cha-98-z6to-d0jn","title":"50mm Pop Up Piston Fits Husqvarna 371XP 372XP Early Saw","description":"\u003cp\u003eRaised-crown 50mm pop-up piston kit, with rings, wrist pin and circlips, that fits the earlier Husqvarna 371XP and 372XP chainsaws. Both generations of these saws are 50mm, so check the ring: a 50 x 1.5mm ring is the earlier engine and takes this piston, and a 50 x 1.2mm ring is the later XT engine, which takes a different one. The raised crown reduces combustion chamber volume and raises compression, giving more low-down torque and easier starting, but it does not reliably add peak power on a stock cylinder. Measure squish clearance with solder through the plug hole before running it, and do not delete or shim the base gasket to clear the dome. Set the high speed mixture slightly rich and run the first tank gently.\u003c\/p\u003e\u003cul\u003e\n\u003cli\u003eFITS HUSQVARNA 371XP AND 372XP, EARLIER SAWS - A raised-crown pop-up piston for the 50mm bore, supplied with rings, wrist pin and circlips.\u003c\/li\u003e\n\u003cli\u003eTHE RING TELLS YOU WHICH SAW YOU HAVE - Both generations are 50mm, so the bore does not separate them. A 50 x 1.5mm ring is the earlier engine and takes this piston; a 50 x 1.2mm ring is the later XT engine and takes a different one.\u003c\/li\u003e\n\u003cli\u003eWHAT A POP-UP DOES - The raised crown reduces combustion chamber volume and raises compression, which gives more low-down torque and easier starting. It does not reliably add peak power on a stock cylinder.\u003c\/li\u003e\n\u003cli\u003eMEASURE SQUISH BEFORE YOU RUN IT - A raised crown uses up squish clearance. Check it with solder through the plug hole, turning the engine through top dead center by hand, and do not delete the base gasket as well: the two changes stack and the crown can reach the head.\u003c\/li\u003e\n\u003cli\u003eDO NOT SHIM THE BASE TO CLEAR THE DOME - Extra base gasket retards every port timing figure and gives back what the compression gained. If the dome will not clear, cut the squish band or use a flat-top piston. Set the high speed mixture slightly rich and run the first tank gently.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Lil Red Barn","offers":[{"title":"Default Title","offer_id":68009607921818,"sku":"98-Z6TO-D0JN","price":39.95,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0397\/2346\/6909\/files\/610JR-LL2JL.jpg?v=1793382582","url":"https:\/\/performancesawsupply.com\/products\/hot-saw-pop-up-piston-compatible-with-husqvarna-371-372-non-x-torq-cha-98-z6to-d0jn","provider":"Performance Saw Supply","version":"1.0","type":"link"}