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Big Mutha' Thumpr 243/257 Hydraulic Flat Cam for Chrysler 426 HEMI

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UPC:
00036584212874
Availability:
This part ships direct from the manufacturer, lead times, stock and shipping may vary.
Weight:
9.79 LBS
$268.74

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A Portion Of The Proceeds From Your Purchase Supports The Development & Reproduction Of High Quality 1963-1991 Restoration Parts.

Big Mutha' Thumpr 243/257 Hydraulic Flat Cam for Chrysler 426 HEMI

Big Mutha' Thumpr 243/257 Hydraulic Flat Cam for Chrysler 426 HEMI

$268.74
Designed to deliver an aggressive, hard-hitting exhaust note at idle, the Thumpr camshaft series from COMP Cams also delivers excellent horsepower gains and a broad torque curve. A perfect choice for muscle cars and street rods, the Thumpr series' early intake valve opening and long exhaust duration create optimum overlap for that race car idle. The Thumpr grinds all require an aftermarket torque converter and lower gear ratio to ensure the drivetrain always puts the engine in its powerband. Additionally, Thumpr camshafts typically deliver reduced vacuum at idle, making a vacuum canister, pump or hydroboost a requirement for vehicles running power brakes.

Installation Instructions

Installation Instructions





Advertised Exhaust Duration296
Advertised Intake Duration279
ApplicationsFits Chrysler 426 HEMI
Assembly Lubricant IncludedYes
Basic Operating RPM Range2,000-5,800
C.A.R.B. E.O. NumberN/A
C.A.R.B. Exempt for California Certified Vehicles Manufactured Before 1965?Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for Federally Certified Vehicles Manufactured Before 1967?Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for Foreign Vehicles Manufactured Before 1967?Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for On-Road Vehicles?No
C.A.R.B. Exempt for Racing and Off-Road Only Vehicles?Yes, but must be a race/competition only vehicle.
C.A.R.B. Exemption ReasonN/A
California Proposition 65WARNING: Cancer and Reproductive Harm P65Warnings.ca.gov
Cam TypeHydraulic Flat Tappet
Camshaft Gear Attachment3-Bolt
Camshaft MaterialCast Iron
Camshaft SeriesThumpr
DescriptionStreet/strip, needs 9.5:1 compression, 2800+ stall, intake, gears and headers, very rough idle.
Engine FamilyChrysler 426 HEMI 8 Cylinder (1966-1971)
Exhaust Duration at .050 inch Lift241
Exhaust Valve Lift0.478
Grind Number295TH7
Intake Duration at .050 Inch Lift227
Intake Valve Lift0.508
Lifter TypeHydraulic Flat Tappet
Lifters IncludedNo
Lobe Separation107
UsageStreet/Strip
Valve Springs RequiredYes

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Parts returned that are not defective, are subject to a 25% restocking charge. JeepRecyclers.com/McDaniel Motor Co. is NOT responsible for any parts that have been altered, modified, disassembled, or damaged by misuse or an accident subsequent to the parts purchase.

Reconditioned parts come with a minimum warranty of 90 days, unless otherwise stated (Refer to product listing for warranty duration). The warranty is void if the parts are not returned in the same condition in which they are sold. Warranties for aftermarket parts are covered by the manufacturer.

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For orders delivered within the continental US where reason for return isn't a result of a JeepRecyclers.com/McDaniel Motor Co. error, the cost of the initial shipping charge and a return fee will be deducted from your refund. A prepaid shipping label(s) will be provided. The flat fee for each item being returned can be found in the chart below:

Retail cost of the item Per Item Return Fee
Less than $25.00 $3.75
From $25.00-$49.99 $5.75
From $50.00-$99.99 $7.75
More than $100.00 $9.75

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