1991 GMC Jimmy Performance Engines

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.

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
• 50 State Street Legal

Fel-Pro gaskets are specifically designed for the repair environment to deliver a reliable seal on even the most troublesome applications. Designed for imperfect sealing surfaces and manufactured with proprietary materials, you can count on Fel-Pro for innovative sealing solutions for the real-world repair environment.

Product Features:

• Fluoroelastomer compound combines optimum resistance to heat, oils and abrasion for longevity.
• Optimizes performance under high crankcase vacuum conditions, elevated temperatures and high RPM levels.
• Not intended for use in emission controlled vehicles.
• Not intended for use in emission controlled vehicles.

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 twelve (12) 3/8 inch-16 x 1 inch bolts & washers

Product Features:

• Zinc plated to resist corrosion and provide a clean professional appearance
• Made from Grade 5 steel for strength and durability
• Flat washers provide uniform clamp load and prevent galling on aluminum intake manifolds
• Allen (socket) Head
• Zinc Plated For Protection

Product Features:

• Case-Hardened Tubing
• Welded Ends
• 5/16 in. Diameter
• Use with or without Hardened Steel Guideplates

Mr. Gasket High Performance Thermostats are designed to resist large variations of coolant pressure at high RPM (revolutions per minute). This allows them to fully open at correct temperature consistently regardless of engine RPM. The design also provides the high flow that engines operated a higher RPM need. This thermostat also features a copper/brass construction to further resist corrosion. Mr. Gasket High Performance / High Flow Thermostats are suitable for street, drag race, or oval track applications.

Product Features:

• Opens At 195 Degrees
• Designed to Resist Large Variations of Coolant Pressure at High RPM
• Fully Opens at Correct Temperature Consistently Regardless of Engine RPM
• For High Performance Street, Drag Race, and Oval Track
• Copper & Brass Construction – Resists Corrosion
• High Flow

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

Complete kit includes retainers and locks. Springs made of highest quality spring wire. Springs precision wound to close tolerances. Includes superior quality steel retainers. Includes 7 degree heat-treated valve stem locks. Retainers and locks are black oxide coated. Non-rotator style: Dyno tested and street proven. Great match to Edelbrock camshaft kit.

Product Features:

• Complete Kit: Includes Retainers And Locks
• Springs Made of Highest Quality Spring Wire
• Springs Precision Wound To Close Tolerances
• Includes Superior Quality Steel Retainers
• Includes 7 deg. Heat-Treated Valve Stem Locks
• Retainers and Locks Black Oxide Coated
• Dyno Tested And Street Proven
• Great Match to Edelbrock Camshaft Kit

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

This Mr. Gasket Deluxe Engine Bolt Kit includes chrome plated grade 5 hex head fasteners with AN type washers for the following: Intake Manifold, Timing Cover, Oil Pan, Fuel Pump, Water Neck, Long Water Pump and Headers. The AN washers have no exposed shoulder which offers a professional appearance.

Product Features:

• Chrome plated
• Grade 5
• AN washers with no exposed shoulder for a professional appearance

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.

Manufactured from high-density cork/rubber blend gasket material. Provides excellent sealing and durability. Complete with molded rubber front/rear oil pan seals. For original equipment replacement and high performance street.

Product Features:

• Manufactured from high-density cork /rubber blend gasket material
• Provides excellent sealing and durability
• Complete with molded rubber front/rear oil pan end seals
• For OE replacement and high performance street use

These Magnum Roller Rocker Arms for Chevy V8 265-400 and V6 200-262 applications are the ultimate street rocker. With a 3/8″ stud diameter and 1.52 ratio, they are designed for serious performance enthusiasts. All Magnum Roller Rocker Arms are constructed

Product Features:

• Roller tip reduces friction while stiff design and superior ratio accuracy yield more effective valve lift
• For applications with less than 350 lbs. of open spring pressure
• Constructed from 8620 chromemoly steel, a superior material that will not flex and ensures maximum lift
• Ultimate street roller rocker arm designed for serious performance enthusiasts

HoleShot 3600 for GM 1965 to 1991 TH400, 425, 375 and 1968 to 1981 TH350, 375B (not 350C) APPLICATION: HoleShot 3600 for GM 1965 to 1991 TH400, 425, 375 and 1968 to 1981 TH350, 375B (not 350C) A higher than stock stall speed as delivered by the Holeshot converter will provide several advantages and benefits in vehicles with modified engines. Many modifications, particularly big cams, tend to reduce low end power and torque. The high stall converter allows the engine to launch the car at higher rpm where more torque is available. The Holeshot is generally a very good choice for the typical street machine that is looking for better launch capability and more strength. Street rods with modified engines will also benefit from a Holeshot converter. If your vehicle is equipped with a plate type nitrous system, you will need a Nitrous Holeshot!! Stall speed listings are based on engines producing 230lb. ft. of torque at 2,500 rpm. More torque at 2,500 rpm will give you more stall speed, less torque at 2,500 rpm will give you less stall speed than the stall speed ratings indicated. Furnace brazed impeller. New precision steel alloy pump drive tube. New heavy duty needle bearing between stator and impeller (not a thrust washer). Needle bearing between stator and turbine. Furnace brazed turbine. Dual pattern drive lugs on some GM Holeshots. New turbine hub. New springs and rollers in stator.

Product Features:

• Furnace Brazed Impeller
• Steel Alloy Pump Drive Tube
• Heavy Duty Needle Bearing
• Between Stator and Turbine
• Furnace Brazed Turbine
• Dual Pattern Drive Lugs
• New Turbine Hub
• New Springs/Rollers In Stator

Product Features:

• 4.37 in. Cylinder Bore Diameter
• 0.039 in. Thickness (Rect. Port)
• 0.38 in. Thickness (Oval Port)
• 9.7cc Vol. (Rect. Port)/10.05cc Vol. (Oval Port)
• Two Piece Configuration

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

Based on performer RPM-series with unique air gap. Air gap cooler and denser mixture for more power. Designed for 1500 to 6500 RPM street-driven power. Dual-plane high-rise intake with 180 degree firing order. Produces incredible top-end horsepower. Retains good throttle response and acceleration. Larger plenum and runners maximize other upgrades. Edelbrock total power package maximizes gains. Available in cast, polished or endurashine finish.

Product Features:

• Based on Performer RPM-Series with Unique Air Gap
• Air Gap Cooler and Denser Mixture for More Power
• Designed for 1500 to 6500 RPM Street-Driven Power
• Dual-Plane High-Rise Intake w/180 deg Firing Order
• Produces Incredible Top-End Horsepower
• Retains Good Throttle Response and Acceleration
• Larger Plenum and Runners Maximizes Other Upgrades
• Edelbrock Total Power Package Maximizes Gains

Product Features:

• For use on Small Block Chevys with 4150 series carb (side mounting) and the Victor Ram base manifold #7075 only
• Made of aluminum with a natural finish
• Hardened washers must be used with intake bolts
• Single Plane
• Made In The USA

VALVE SEALS, O-RING 11/32″ 1 ST

COMP Cams offers a complete line of valve stem seals, from the umbrella seals to the positive-stop Teflon seal. These seals are a must to keep unwanted oil from entering the combustion chamber through the clearance in the valve guides. The umbrella seal is normally used when a larger-than-stock diameter spring is used, in the case of a double spring, the positive-stop Teflon seal is used. The umbrella seals require no machining, but with the Teflon seal it is necessary to disassemble the heads and machine the top of the guide with a special .530 diameter cutter. Whenever you are planning an engine overhaul or a cam change, don’t forget the valve seals.

Product Features:

• Work with .530″ guides and 3/8″ valve stem diameter
• Valve stem oil seals keep unwanted oil from entering the combustion chamber
• Several different types of valve seals are offered

Product Features:

• Clean Positive Seal
• Embossed Silicone Bead Surrounding The Port
• Matched To Manifolds And Cylinder Heads

Mr. Gasket Performance Intake Gaskets are manufactured from cellulose/nitrile composition gasket material. This is a low density material that conforms well to irregular surfaces and has very good crush resistance at high flange pressures. They provide excellent sealing and durability as the material is designed for sealing gasoline, oils, water and coolant in applications up to 350 degrees Fahrenheit. While die-cut for an excellent fit, they can be trimmed if necessary for modified port applications. Comes complete with front & rear manifold end seals. For original equipment replacement, high performance street, drag race and oval track.

Product Features:

• Manufactured from cellulose/nitrile composition gasket material
• Provides excellent sealing and durability
• Die-cut for an excellent fit
• Can be trimmed if necessary for modified port applications
• Complete with manifold end seals & distributor gaskets if applicable
• For OE replacement, high performance street, drag race and oval track use

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

Product Features:

• Steel core gasket construction
• Exclusive design permits significantly faster gasket installation while eliminating potential sealing leak paths.
• Not intended for use in emission controlled vehicles.

Product Features:

• Replacement Gasket Set For PN[4242]

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

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.

An older member of the COMP Cams grind family, the Magnum series of camshafts offers excellent performance gains over stock without the added wear and tear associated with more aggressive camshafts.

Product Features:

• Best with aftermarket torque converters and 9.5:1 compression.
• Great high RPM power.
• Easy on valve train parts.
• Can be used with mild ratio rocker arms and traditional performance valve springs.

HYDRAULIC – Thumpr: High performance street, stock converter ok, best with 2000+ converter and gears. Choppy/thumping idle.

Product Features:

• HYDRAULIC – Thumpr: High performance street, stock converter ok, best with 2000+ converter and gears. Choppy/thumping idle.
• 279/296 Advertised Duration, 227/241 Duration @ .050″, .498″/.483″ Lift, 107 Lobe Separation
• Valve spring upgrade required