400 Aluminum Tall Deck Bare Race Block


  • A-356 aluminum tall deck competition block
  • Splayed 4-bolt steel mains
  • 4.117″ rough bore; 4.135″ max bore
  • Dry sump use only
  • Tested to over 800 HP


Shipping is free, but there is a delivery fee for residential addresses.

400 Aluminum Tall-Deck Bare Race Block

P/N 24502495

– A-356 aluminum competition block
– CNC-machined
– Siamesed bores with increased wall thickness
– 4.117″ rough-finished bore
– 4.135″ maximum bore
– 4.125″ maximum stroke
– Splayed 4-bolt steel mains
– 400 main size
– Dry sump use only
– Tested to more than 800 horsepower!


400 Aluminum Tall Deck Bare Race Block

24502495 Chevrolet Cylinder Block

Less weight and the same great horsepower are the benefits of a Chevrolet Performance Aluminum Race Block. Chevrolet Performance Aluminum Race Blocks provide the same competition-level strength and reliability of our cast-iron Race Blocks, but their lighter weight improves chassis dynamics. The super-tough A-356 aluminum competition blocks are CNC-machined to +/- 0.005-inch tolerances. Chevrolet Performance Aluminum Race Blocks are ideal for competition applications or high horsepower turbocharged engines.

Race Block Technical Notes:

ユ Extra-thick deck surface with blind-tapped head bolt holes for improved head gasket sealing
ユ Centrifugally spun cast-iron cylinder sleeves
ユ 2-piece rear-main crankshafts and pre-1986 oil pans required
ユ Enlarged cam bosses allow machining for larger cam bearings
ユ 2.000″ O.D. (1.867″ I.D.) cam bearings P/N 12370843 required
ユ Blocks may require clearancing at top of lifter bores (0.842″) for some roller lifters
ユ Timing system clearance should be checked before engine assembly
ユ Extra-thick main bearing bulkhead machined at 5ᄚ
ユ Premium main studs and steel main bearing caps
ユ Priority main oiling system
ユ Billet wet sump rear main cap can be converted to dry sump with plugs
ユ Oil dipstick holes not drilled
ユ Comes with dowel pins

Note: Proposed applications have not been specifically tested or validated by Chevrolet Performance.

Prop65WARNING: These auto parts can expose you to chemicals including phthalates and lead. Installing or using these parts can expose you to other parts containing these chemicals and to engine exhaust, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.