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Universal Fit

Need parts that work across platforms? Our Universal Fit collection includes components...

Universal Fit

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Welcome to WrenchIt — premium performance parts for serious builders.

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Collection: Mopar Small Block

Mopar Small Block specialists — featuring parts for 318, 340, and 360 engines. Designed to enhance performance and preserve the legacy of Chrysler’s small block power.

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193 products

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Speedmaster (193 products)

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193 products

Pontiac 455 4340 Forged Steel Crankshaft ST-4.25 M-3.25 RJ-2.200 RMS-2Pc Ext

Sale

Pontiac 455 4340 Forged Steel Crankshaft ST-4.25 M-3.25 RJ-2.200 RMS-2Pc Ext

Vendor:
Speedmaster

Regular price $965.30 USD

Regular price ~~$1,135.70 USD~~ Sale price $965.30 USD

Sale
Ford FE 390 427 4340 Forged Steel Perform Crankshaft ST-4.125 M-2.7488 RJ-2.4384

Sold out

Ford FE 390 427 4340 Forged Steel Perform Crankshaft ST-4.125 M-2.7488 RJ-2.4384

Vendor:
Speedmaster

Regular price $938.40 USD

Regular price Sale price $938.40 USD

Sold out
Chevy BBC 454 4340 Forged Steel ST-4.500 8-Counterweight Peformance Crankshaft

Sale

Chevy BBC 454 4340 Forged Steel ST-4.500 8-Counterweight Peformance Crankshaft

Vendor:
Speedmaster

Regular price $820.90 USD

Regular price ~~$965.70 USD~~ Sale price $820.90 USD

Sale
Ford 351C 4340 Forged Steel Crankshaft ST-3.750 M-2.749 MRL-6.2 Bal-Int

Ford 351C 4340 Forged Steel Crankshaft ST-3.750 M-2.749 MRL-6.2 Bal-Int

Vendor:
Speedmaster

Regular price $1,173.50 USD

Regular price Sale price $1,173.50 USD
Chevy LS 4340 Forged Crankshaft ST-4.000 M-LS RJ-2.1 MRL-6.098 RMS-1Pc Bal-Int

Chevy LS 4340 Forged Crankshaft ST-4.000 M-LS RJ-2.1 MRL-6.098 RMS-1Pc Bal-Int

Vendor:
Speedmaster

Regular price $1,198.10 USD

Regular price Sale price $1,198.10 USD
Ford 351C 4340 Forged Steel Crankshaft ST-4.170 M-2.749 MRL- 6.0 Bal-Ext

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Ford 351C 4340 Forged Steel Crankshaft ST-4.170 M-2.749 MRL- 6.0 Bal-Ext

Vendor:
Speedmaster

Regular price $680.00 USD

Regular price Sale price $680.00 USD

Sold out
Ford 351C 4340 Forged Steel Crankshaft ST-4.100 M-2.749 MRL- 6.0 Bal-Ext

Sold out

Ford 351C 4340 Forged Steel Crankshaft ST-4.100 M-2.749 MRL- 6.0 Bal-Ext

Vendor:
Speedmaster

Regular price $868.40 USD

Regular price Sale price $868.40 USD

Sold out
Ford 351W Windsor 4340 Forged Crankshaft ST-4.250 M-351C RJ-2.100 Ext

Ford 351W Windsor 4340 Forged Crankshaft ST-4.250 M-351C RJ-2.100 Ext

Vendor:
Speedmaster

Regular price $868.40 USD

Regular price Sale price $868.40 USD
Ford 351W Windsor 4340 Forged Crankshaft ST-4.170 M-351C RJ-2.100 Ext

Ford 351W Windsor 4340 Forged Crankshaft ST-4.170 M-351C RJ-2.100 Ext

Vendor:
Speedmaster

Regular price $868.40 USD

Regular price Sale price $868.40 USD
Ford 351W Windsor 4340 Forged Crankshaft ST-4.100 M-351C RJ-2.100 Ext

Ford 351W Windsor 4340 Forged Crankshaft ST-4.100 M-351C RJ-2.100 Ext

Vendor:
Speedmaster

Regular price $868.40 USD

Regular price Sale price $868.40 USD
Ford 351W Windsor 4340 Forged Crankshaft ST-4.100 M-351W RJ-2.100 Ext

Sale

Ford 351W Windsor 4340 Forged Crankshaft ST-4.100 M-351W RJ-2.100 Ext

Vendor:
Speedmaster

Regular price $1,240.50 USD

Regular price ~~$1,459.50 USD~~ Sale price $1,240.50 USD

Sale
Ford 351W Windsor 4340 Forged Crankshaft ST-3.750 M-351W RJ-2.310 Ext

Sale

Ford 351W Windsor 4340 Forged Crankshaft ST-3.750 M-351W RJ-2.310 Ext

Vendor:
Speedmaster

Regular price $692.10 USD

Regular price ~~$814.30 USD~~ Sale price $692.10 USD

Sale
Ford 351W Windsor 4340 Forged Crankshaft ST-3.850 M-351W RJ-2.310 Bal-Int

Sold out

Ford 351W Windsor 4340 Forged Crankshaft ST-3.850 M-351W RJ-2.310 Bal-Int

Vendor:
Speedmaster

Regular price $868.40 USD

Regular price Sale price $868.40 USD

Sold out
Ford 289 302 5.0L 4340 Forged Crankshaft ST-3.400 M-2.2486 RJ-2.123 Bal-Int

Ford 289 302 5.0L 4340 Forged Crankshaft ST-3.400 M-2.2486 RJ-2.123 Bal-Int

Vendor:
Speedmaster

Regular price $1,036.16 USD

Regular price Sale price $1,036.16 USD
Chevy BBC 454 4340 Forged Steel Crankshaft ST-4.250 M-Std RJ-2.2 RMS-1Pc Bal-Int

Sale

Chevy BBC 454 4340 Forged Steel Crankshaft ST-4.250 M-Std RJ-2.2 RMS-1Pc Bal-Int

Vendor:
Speedmaster

Regular price $1,287.10 USD

Regular price ~~$1,514.20 USD~~ Sale price $1,287.10 USD

Sale
Chevy BBC 454 4340 Forged Steel Crankshaft ST-4.500 M-Std RJ-2.2 RMS-2Pc Bal-Int

Sale

Chevy BBC 454 4340 Forged Steel Crankshaft ST-4.500 M-Std RJ-2.2 RMS-2Pc Bal-Int

Vendor:
Speedmaster

Regular price $728.70 USD

Regular price ~~$857.10 USD~~ Sale price $728.70 USD

Sale
Chevy BBC 454 4340 Forged Steel Crankshaft ST-4.250 M-Std RJ-2.2 RMS-2Pc Bal-Int

Chevy BBC 454 4340 Forged Steel Crankshaft ST-4.250 M-Std RJ-2.2 RMS-2Pc Bal-Int

Vendor:
Speedmaster

Regular price $1,213.50 USD

Regular price Sale price $1,213.50 USD
Chevy 400 4340 Forged Steel Crankshaft ST-4.000 M-400 RJ-2.1 RMS-2Pc Bal-Int

Chevy 400 4340 Forged Steel Crankshaft ST-4.000 M-400 RJ-2.1 RMS-2Pc Bal-Int

Vendor:
Speedmaster

Regular price $1,112.00 USD

Regular price Sale price $1,112.00 USD
Chevy 400 4340 Forged Steel Crankshaft ST-3.750 M-400 RJ-2.1 RMS-2Pc Bal-Int

Chevy 400 4340 Forged Steel Crankshaft ST-3.750 M-400 RJ-2.1 RMS-2Pc Bal-Int

Vendor:
Speedmaster

Regular price $861.10 USD

Regular price Sale price $861.10 USD
Chevy SBC 350 4340 Forged Steel Crankshaft ST-3.750 M-350 RJ-2.1 RMS-1Pc Bal-Int

Chevy SBC 350 4340 Forged Steel Crankshaft ST-3.750 M-350 RJ-2.1 RMS-1Pc Bal-Int

Vendor:
Speedmaster

Regular price $1,112.00 USD

Regular price Sale price $1,112.00 USD
Chevy SBC 350 4340 Forged Steel Crankshaft ST-3.480 M-350 RJ-2.1 RMS-1Pc Bal-Int

Sold out

Chevy SBC 350 4340 Forged Steel Crankshaft ST-3.480 M-350 RJ-2.1 RMS-1Pc Bal-Int

Vendor:
Speedmaster

Regular price $732.00 USD

Regular price ~~$861.10 USD~~ Sale price $732.00 USD

Sold out
Chevy SBC 350 4340 Forged Steel Crankshaft ST-4.000 M350 RJ21 RMS-2Pc Bal-Int LW

Sold out

Chevy SBC 350 4340 Forged Steel Crankshaft ST-4.000 M350 RJ21 RMS-2Pc Bal-Int LW

Vendor:
Speedmaster

Regular price $751.50 USD

Regular price Sale price $751.50 USD

Sold out
Chevy SBC 350 4340 Forged Steel Crankshaft ST-4.000 M-350 RJ-2.1 RMS-2Pc Bal-Int

Sale

Chevy SBC 350 4340 Forged Steel Crankshaft ST-4.000 M-350 RJ-2.1 RMS-2Pc Bal-Int

Vendor:
Speedmaster

Regular price $1,079.90 USD

Regular price ~~$1,079.94 USD~~ Sale price $1,079.90 USD

Sale
Chevy SBC 350 4340 Forged Steel Crankshaft ST-3.750 M-350 RJ-2.1 RMS-2Pc Bal-Int

Chevy SBC 350 4340 Forged Steel Crankshaft ST-3.750 M-350 RJ-2.1 RMS-2Pc Bal-Int

Vendor:
Speedmaster

Regular price $1,001.50 USD

Regular price Sale price $1,001.50 USD

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