GMC K25 Performance Engines

Your One-Stop Shop For Trusted GMC K25 Performance Engines

If you’re in search of GMC K25 Performance Engines aftermarket or OEM parts, consider your search over! Advance Auto Parts carries 281 Performance Engines from top brands with prices ranging from $7.99 to $1,645.99.

Beyond great prices, we stock trusted brands manufacturing all types of Performance Engines for your GMC K25.

And don’t forget to read customer reviews across all Performance Engines categories in our catalog. Buy with confidence by leveraging past customer experiences of our aftermarket and OEM parts.

At Advance Auto Parts, we don’t think top quality Performance Engines have to cost top dollar, and we prove it. Browse our top GMC K25 Performance Engines below, order online to ship to your home, or head into your nearest Advance Auto Parts location to get started.

Essential GMC K25 Performance Engines

Competition Cams – Big Mutha’ Thumpr 243/257 Hydraulic Roller Cam (Part No.12-602-8)

Big Mutha' Thumpr 243/257 Hydraulic Roller Cam

from

$549.99
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.

Product Features:
  • Early intake valve opening and long exhaust duration create optimum overlap for powerful, hard-hitting exhaust note.
  • Best with aftermarket converters and more rear gear.
  • Three unique cam designs for each application that deliver excellent horsepower gains and broad torque curve; perfect choice for muscle cars and street rods.
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Mr. Gasket – Ultra Seal: Cylinder Head Bolts (Part No.941G)

Ultra Seal: Cylinder Head Bolts

from

$73.99
These grade 8 alloy steel, longer length bolts are designed to compensate for thread length lost when using head bolt washers. This allows increased torque and clamping. Set of 16 does one cylinder head.

Product Features:
  • Cylinder Head Bolts
  • Longer-Than-Stock
  • High Quality Grade 8 Alloy
  • Increase Torque Settings
  • Higher Clamp Loads On Gasket
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Edelbrock – Performer Big-Block Chevy Oval Port Hydraulic Flat Tappet Cam (Part No.60499)

Performer Big-Block Chevy Oval Port Hydraulic Flat Tappet Cam

from

$1251.99
Product Features:
  • Complete Single For Flat Tappet
  • 100cc Combustion Chamber Volume
  • 290cc Intake/110cc Exhaust Runner Volume
  • 2.19 in. Intake/1.88 in. Exhaust Valve Diameter
  • 0.562 in. Deck Thickness
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Edelbrock – Sure Seat Valve Springs for Chevy 262-400 V8 1957-95 (Part No.5802)

Sure Seat Valve Springs for Chevy 262-400 V8 1957-95

from

$64.99
Springs made of highest quality spring wire. Springs precision wound to close tolerances. Non-Rotator style: Dyno tested and street proven. Great match to Edelbrock camshaft kit.

Product Features:
  • For Use With Cast Iron Heads
  • Springs Made of Highest Quality Spring Wire
  • Springs Precision Wound To Close Tolerances
  • Use with Original Equipment Heads Only
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Mr. Gasket – Intake Manifold Bolts (Part No.957G)

Intake Manifold Bolts

from

$29.99
These grade 5 hex head bolts are brite zinc plated for protection and appearance. Hardened flat washers provide uniform torque & prevent galling on aluminum manifolds. Includes sixteen (16) 3/8 inch-16 x 1-1/4 inch bolts & washers

Product Features:
  • Zinc plated Grade 5 steel
  • Flat washers provide uniform clamp load and prevent galling on aluminum intake manifolds
  • Ideal For Minimal Space
  • 12-Point Head And Flange
  • Zinc Plated For Protection
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Competition Cams – Set of 16 O-Ring Valve Seals for Stock Guide Size, 11/32" Valve Stem (Part No.501-16)

Set of 16 O-Ring Valve Seals for Stock Guide Size, 11/32" Valve Stem

from

$223.99
VALVE SEALS, O-RING 11/32″ 1 ST
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Mr. Gasket – Engine Dress-Up Kit (Part No.9834BP)

Engine Dress-Up Kit

from

$134.99
Includes: 2 short flat black valve covers 2 valve cover gaskets 1 flat black push-on breather 1 flat black dipstick & tube 1 flat black timing chain cover 1 flat black timing tab 1 rubber grommet for valve cover PCV hole 1 breather grommet

Product Features:
  • Ideal Starter Kit
  • Enhances Appearance
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FEL-PRO Performance – Cylinder Head Gasket: Steel Core Composite, Without Head Bolts (Part No.1010)

Cylinder Head Gasket: Steel Core Composite, Without Head Bolts

from

$51.99
Fel-Pro Performance Gaskets deliver reliable sealing under grueling racing conditions

Product Features:
  • PROPRIETARY COATING – Nonstick anti-friction coating seals small surface imperfections
  • NO RETORQUE DESIGN – Steel core helps eliminate the need for retorquing head bolts
  • SUPERIOR SEAL – Precise embossed Printoseal sealing beads at all vital areas to eliminate leak paths
  • STRONG AND DURABLE – Features graphite or reinforced fiber facing material and steel armor for strength and durability
  • DESIGNED FOR IMPERFECT SEALING SURFACES – Engineered and manufactured specifically for the repair environment to help seal imperfect sealing surfaces
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Weiand – Action +Plus; Water Pump (Part No.9242P)

Action +Plus; Water Pump

from

$249.99
Weiand’s light weight, performance aluminum mechanical Action-Plus water pumps give a weight saving of 30 percent to 50 percent over stock cast-iron pumps. These pumps feature a premium quality bearing and seal that have twice the load capacity of stock pumps. Weiand’s exclusive housing counter bore keeps the bearing form walking out. All pumps are designed with the necessary bracket bosses and water connections to fit popular street applications.

Product Features:
  • Twisted Snout Water Pump Design For Updated Style
  • Street Performance
  • Heavy Duty Shaft w/5/8 in. Pilot
  • Six-Blade Stamped Steel
  • Anti-Cavitation Impeller
  • 100 Percent Leak Tested
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Edelbrock – Street Tunnel Ram Big Block Chevy 2-O Intake Manifold (Part No.7115)

Street Tunnel Ram Big Block Chevy 2-O Intake Manifold

from

$838.99
For 3500 to 7500 PRM. Use where low-end torque is not a prime factor. Great for engines with slightly modified heads. HEI ignition will not clear manifold. Street machines, street rods, pro-street and marine.

Product Features:
  • For 3500 to 7500 RPM
  • Use Where Low-End Torque is Not a Prime Factor
  • Great For Engines w/Slightly Modified Heads
  • Top Has Vacuum Outlet for Power Brakes
  • Will Accept Forward and Sideways Mounted Carbs
  • Carburetor Center-to-Center Dimensions 9.38 in
  • HEI Ignition Will Not Clear Manifold
  • Street Machines; Street Rods; Pro-Street; Marine
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Edelbrock – Performer Series Retainer (Qty 16) (Part No.9721)

Performer Series Retainer (Qty 16)

from

$100.99
Valve spring retainers for use OE cast iron heads. Superior quality heat-treated steel. Machined for strength with black oxide finish. Finish ensures rust and corrosion protection.

Product Features:
  • Valve Spring Retainers for Use OE Cast Iron Heads
  • Superior Quality Heat-Treated Steel
  • Machined for Strength with Black Oxide Finish
  • Finish Ensures Rust and Corrosion Protection
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Mr. Gasket – Cam Bolt Lock Plate Kit (Part No.948G)

Cam Bolt Lock Plate Kit

from

$20.99
Mr. Gasket cam locking plates feature a steel retainer plate designed to secure the cam gear bolts from coming loose and backing out, preventing costly engine damage. Retainer plate fits under bolt heads allowing tabs to be bent against hex head flats creating a secure positive lock.

Product Features:
  • Black oxide finished steel
  • Includes (3) grade 5 bolts & locking plate
  • Fits Chevrolet Small and Big Block without OE roller cam
  • Tabs bend up around bolt head to secure
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Mr. Gasket – Rear Main Seal Gasket (Part No.1960)

Rear Main Seal Gasket

from

$27.99
This Mr. Gasket Rear Main Seal is made from silicone to allow the seal to handle extreme engine oil temperature. It also provides for an upgrade for that leaky rope style seal and is a direct replacement for a rubber main seal. It’s also injection molded for a precise fit.

Product Features:
  • Repairs That Leaky Rear Main Sail
  • Silicone Rubber to Withstand Extreme Engine Oil Temperatures
  • Upgrade for Rope Seal Equipped Cars or Direct Replacement for Rubber Main Seal
  • Injection Molded for Precise Fit
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FEL-PRO Performance – Oil Pan Gasket Set: High-Temperature Rubber-Coated Fiber, 5 Piece Set (Part No.1803)

Oil Pan Gasket Set: High-Temperature Rubber-Coated Fiber, 5 Piece Set

from

$26.99
Fel-Pro Performance Gaskets deliver reliable sealing under grueling racing conditions

Product Features:
  • Felcoid/Plus gaskets have a fiber sheet core and a latex rubber coating to eliminate potential leakage paths. The core material resists crushing and splitting, while providing excellent blowout resistance.
  • With steel core to provide ultimate excellent blowout resistance.
  • Not intended for use in emission controlled vehicles.
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Mr. Gasket – Cylinder Head Dowel Pins (Part No.4375)

Cylinder Head Dowel Pins

from

$17.99
Dowel pins are precision machined and case hardened for accurate head alignment. Two per set. 5/16 inch x 5/8 inch

Product Features:
  • Precision Machined
  • Case Hardened
  • Give Accurate Alignment
  • 2 Per Set
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Mr. Gasket – Timing Cover Seal (Part No.17)

Timing Cover Seal

from

$34.99
If you are changing your camshaft or replacing the timing set, make sure to replace this seal at the same time! Made from Nitrile rubber.

Product Features:
  • Nitrile Rubber And High Density Cork
  • Will Not Shrink Or Stick
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Edelbrock – Performer-Link Adjustable True-Roller Timing Chain Set (Part No.7810)

Performer-Link Adjustable True-Roller Timing Chain Set

from

$78.99


Product Features:
  • Solid Bushing Chain Resists Stretching
  • For Use with Stock or Edelbrock Camshafts
  • Stressproof Steel Crank Gears
  • 3 Keyway Setting Points To Ensure Accurate Timing
  • True Bearing Surface Rolls with the Sprockets
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Edelbrock – Pushrod Set for S/B Chevy (Part No.9630)

Pushrod Set for S/B Chevy

from

$199.99


Product Features:
  • Case-Hardened Tubing
  • Welded Ends
  • 5/16 in. Diameter
  • Use with or without Hardened Steel Guideplates
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Competition Cams – High Energy 212/212 Hydraulic Flat Cam/Lifter Kit (Part No.CL11-203-3)

High Energy 212/212 Hydraulic Flat Cam/Lifter Kit

from

$596.99
Ideal for use with mainly stock components like rocker arms, intake manifolds, cylinder heads, compression ratio, torque converters and rear gear ratios, the High Energy camshaft grind family is a great choice for street performance applications.

Product Features:
  • Good blend of efficiency and performance.
  • Perfect choice for performance street rebuilds.
  • Work well with mainly stock components such as rockers, manifolds, heads, compression, torque converters and gears.
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Competition Cams – Ultra Pro Magnum Rocker Arm Set with 1.6 Ratio for Chevrolet SBC with 7/16" Stud (Part No.1605-16)

Ultra Pro Magnum Rocker Arm Set with 1.6 Ratio for Chevrolet SBC with 7/16" Stud

from

$476.99
Ultra Pro Magnum Rocker Arm Set with 1.6 Ratio for Chevrolet SBC with 7/16" Stud

Mr. Gasket – Ultra Seal: Harmonic Balancer Bolt/Washer Kit (Part No.945G)

Ultra Seal: Harmonic Balancer Bolt/Washer Kit

from

$15.99
This is a high quality bolt set that is made of grade 8 steel and will meet your requirements for a quality bolt set, this set will work on original equipment, high performance street, drag or circle track applications.

Product Features:
  • Has A Zinc Dichromate Finish
  • Made Of High Quality Grade 8 Steel
  • Has A Tall Hex Head To Prevent Wrench Slipping Off
  • Extra Thick Parallel Ground Washer
  • Washer Provides More Accurate And Uniform Torque
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Mr. Gasket – Water Neck (Part No.9845)

Water Neck

from

$34.99
Precision die-cast for a great fit, these water necks are first polished to a high luster, then chrome plated. Comes with gasket and mounting bolts.

Product Features:
  • Prevents Water Leaks
  • Precision Die Cast
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Mr. Gasket – Premium Quality Thermostat Gasket with Solid Aluminum Carrier (Part No.738G)

Premium Quality Thermostat Gasket with Solid Aluminum Carrier

from

$34.99
Edge molded rubber water outlet gasket is reusable, great for engines that require regular disassembling for maintenance. Incorporates solid aluminum carrier for strength and rigidity. Can be used with OE replacement or aftermarket chrome water outlets. Requires no gasket sealer.

Product Features:
  • Edge Molded Rubber Water Outlet Gasket Is Reusable
  • Requires No Gasket Sealer
  • Solid Aluminum Carrier For Strength/rigidity
  • Reusable – Ideal for Engines That Are Frequently Taken Apart & Reassembled
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FEL-PRO Performance – Engine Valve Cover Gasket Set (Part No.1606)

Engine Valve Cover Gasket Set

from

$29.99
Fel-Pro Performance Gaskets deliver reliable sealing under grueling racing conditions

Product Features:
  • Blue Stripe performance cork-rubber gaskets use cork particles evenly distributed throughout a rubber binder resulting in a compressible gasket without leak paths.
  • Not intended for use in emission controlled vehicles.
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FEL-PRO Performance – Engine Valve Cover Gasket Set (Part No.1640)

Engine Valve Cover Gasket Set

from

$22.99
Fel-Pro Performance Gaskets deliver reliable sealing under grueling racing conditions

Product Features:
  • Blue Stripe performance cork-rubber gaskets use cork particles evenly distributed throughout a rubber binder resulting in a compressible gasket without leak paths.
  • Not intended for use in emission controlled vehicles.
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Performance Engines Brands You Can Trust For Your GMC K25

7 trusted brands of Performance Engines line our shelves, ready to help keep your GMC K25 running smooth. Below are some of the most popular brands and their top Performance Engines offerings:

Popular B & M Performance Engines

B & M products for the GMC K25 span several categories. Some of the highest-rated B & M Performance Engines that will fit your GMC K25 are:
Tork Master 2400
from $373.99
(1)
Tork Master 2400
Performance Torque Converters

Top GMC K25 Performance Engines from Mr. Gasket

Your GMC K25 will be purring again thanks to Mr. Gasket brand Performance Engines available for online order or in-store pick up. Popular Mr. Gasket parts include:
High Performance 180 Degree Thermostat for Increased Flow
from $29.99
(20)
High Performance 180 Degree Thermostat for Increased Flow
Performance Engine Coolant Thermostats
High Performance Thermostat - 160 Degree Brass & Copper
from $29.49
(12)
High Performance Thermostat – 160 Degree Brass & Copper
Performance Engine Coolant Thermostats
Ultra Seal: Harmonic Balancer Bolt/Washer Kit
from $15.99
(12)
Ultra Seal: Harmonic Balancer Bolt/Washer Kit
Performance Engine Harmonic Balancers

Most Purchased GMC K25 Performance Engines from Edelbrock

When you buy the most frequently purchased Edelbrock brand Performance Engines, you can be confident it will be the right part for your GMC K25. Here are the Edelbrock Performance Engines Advanced Auto customers buy the most:
Performer EPS Intake Manifold for 1955-86 Small-Block Chevy
from $195.99
(7)
Performer EPS Intake Manifold for 1955-86 Small-Block Chevy
Performance Intake Manifolds
High Performance 180 Degree Thermostat for Increased Flow
from $29.99
(20)
High Performance 180 Degree Thermostat for Increased Flow
Performance Engine Coolant Thermostats
Cylinder Head Gasket: Multi-Layered Steel, Without Head Bolts
from $42.49
(1)
Cylinder Head Gasket: Multi-Layered Steel, Without Head Bolts
Performance Engine Cylinder Head Gaskets

FAQs for GMC K25 Performance Engines

What are the most purchased Performance Engines for the GMC K25?

Out of 281 Performance Engines for the GMC K25, the most popular in our inventory are:
Performer EPS Intake Manifold for 1955-86 Small-Block Chevy
from $195.99
(7)
Performer EPS Intake Manifold for 1955-86 Small-Block Chevy
Performance Intake Manifolds
Intake Manifold Gasket for 1958-1986 Small-Block Chevy
from $28.99
(12)
Intake Manifold Gasket for 1958-1986 Small-Block Chevy
Performance Engine Intake Manifold Gaskets

What are the top-rated GMC K25 Performance Engines?

Top-rated Performance Engines for your GMC K25 based on customer reviews/ratings are:
Big Mutha' Thumpr 243/257 Hydraulic Flat Cam/Lifter Kit
from $914.99
(13)
Big Mutha’ Thumpr 243/257 Hydraulic Flat Cam/Lifter Kit
“Worked prefect. Gave me the Hi speed blower back”
Ultra Seal: Intake Gasket
from $56.99
(5)
Ultra Seal: Intake Gasket
“I bought this to replace the CV Axle because the inner boot on my old axle was flinging grease. This part was a perfect replacement for my 2008 Honda ”