SRP 206072 Oldsmobile 455 forged flat top pistons. This piston is .030 oversized providing 461 cubic inches. Bore size is 4.155, stroke 4.250, use rod length of 6.735. Compression height is 1.750, dome volume is -5cc. Weights in at 557 grams per piston. Made of 4032 low expansion, high silicon aluminum alloy, heat treated to SRP specifications. Forced pin oiler for increased wrist pin lubrication. CNC machined ring grooves accept 1/16", 1/16" and 3/16" rings. Sold as a set of 8 forged Oldsmobile 455 pistons. Wrist pins and double spiro locks are included. Provides 12.1 compression with a 72cc chamber cylinder head Provides 11.6 compression with a 80cc chamber cylinder head. Provides 10.9 compression with a 84cc chamber cylinder head. Made of 4032 wrought aluminum alloy, designed for street and strip applications utilizing compression ratios that are compatible with pump gas. These pistons also provide a quieter engine on cold start-up. Features symetrical valve pockets fully radiused. Honed pin bore, forged side relief. Full floating wrist pin. Double spiro locks. Machined oil drain back holes (not slotted). Pressure fed pin oilers. SRP pistons are forged from wrought alluminum alloys. Wrought aluminum is 20% stronger than aluminum bar stock and 50% stronger than cast aluminum pistons. SRP uses only the highest grade wrought aluminum alloys to make a stronger, lighter piston. These aerospace quality alloys have been rigourously tested and found to be the most durable material for this application. To optimize the weight of the piston, application specific forgings are designed in 3D computer modeling programs. This makes it possible to have consistent dome thickness which will not compromise the durability of the piston. All SRP pistons feature fully CNC machined domes, dishes and valve reliefs to give you precise compression ratios and consistent weights. All SRP pistons incorporate CNC diamond turned skirts to provide you with a better, more consistent finish, and have CNC honed pin bores and are thoroughly deburred prior to cleaning and packaging so no prep work is required. SRP pistons are ready to run right out of the box. ORDERING NOTE: Pistons are not returnable. Please be sure to check your engines oversize requirements, cam requirements and head and piston to valve clearance requirements before ordering. We recommend that this be done by an experienced and competant engine builder. SRP 206072 forged pistons Oldsmobile 455 flat top pistons .030 oversize 206072 We welcome CANADIAN customers! For ordering information, click on "Canadian Order Info" at the top left side of this page. LOW COST SHIPPING! Just $12.95 to ship your entire order by U.P.S. ground within the continental United States. Purchase any quantity of items and you pay just $12.95 to have it shipped! The more you order, the more you save! (Orders to Hawaii, Puerto Rico, Virgin Islands, and some parts of Alaska will have additional shipping charges. Customers located in these areas will be emailed the shipping costs for approval before we ship the order.) We use Postal Priority for APO and FPO addresses only. Additional shipping charges may apply to these addresses.