Adjustable Idler-Tensioner Assembly Small Block Chevy(Crate Kit Replacement)
InfoVehicle Info Needed
KRCPART NUMBER: 612-40400360

Adjustable Idler-Tensioner Assembly Small Block Chevy(Crate Kit Replacement)

$24052
ShippingShips on 11/06/2026
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Chevy
    Adjustable Idler-Tensioner Assembly
  • Small Block Chevy(Crate Kit Replacement)

    Why is an idler tensioner necessary?
    KRC's idler tensioner is essential on dirt cars. Belt slippage can occur on cars that exceed 7,000 RPM and/or use a large or heavy fixed fan blade or a fan blade with a lot of pitch, which potentially causes overheating & pulleys to wear faster. This occurs on both single drive belt and pulley systems with a power steering pump mounted on the front of the engine.

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    The reason for this problem is the centrifugal force from the fan as it decelerates. The fan belt and pulleys are required to work like brake shoes to slow the fan. The belt stretches so it slips while braking, inducing heat into the belt. The belt will continue to stretch as the race goes on, causing engine temperature to slowly climb. KRC's extensive testing has proven the only way to properly tension the belt to prevent slippage is with an idler pulley mounted on the passenger side of the engine. This helps the engine run cooler and keeps the belt tighter, allowing faster acceleration out of turns & harder braking on corners.

Part TypePulley Kit
Product LineKRC Idler & Tensioner Pulley Kits
BrandKRC
Package Height2.3
Package Width8.1
Package Length12.2
Weight2.47 PG
Part CategoryPerformance Parts
Part FitmentSemi Universal
Vendor Part Number40400360
Package Qty1
Package TypeEA
Some parts are not legal for use in California or other states with similar laws / regulations
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