HI-BOOST (HB series) of performance throttle bodies. Specifically developed for severe duty and high boost applications, the new design provides improved performance and durability. We start with a sealed shaft that is pressure tested to 100 psi and stable under the high engine temperatures and high inlet air temps seen in competition and high-power street applications. Next, we've redesigned the mounting coupler for the TPS sensor to eliminate erratic signals sometimes seen under high boost. Then the blade is installed in a split-shaft for superior strength – counter-sunk mounting screws hold the blade in a contoured design for improved airflow at full throttle.

HI-BOOST (HB series) of performance throttle bodies. Specifically developed for severe duty and high boost applications, the new design provides improved performance and durability. We start with a sealed shaft that is pressure tested to 100 psi and stable under the high engine temperatures and high inlet air temps seen in competition and high-power street applications. Next, we've redesigned the mounting coupler for the TPS sensor to eliminate erratic signals sometimes seen under high boost. Then the blade is installed in a split-shaft for superior strength – counter-sunk mounting screws hold the blade in a contoured design for improved airflow at full throttle.

Racers spoke and we delivered! New for 2021, the 123mm “HB” will join Wilson Manifold’s Hi-Boost throttle body line up. Specifically developed for severe duty and high boost applications, the new design provides industry leading performance and durability. We start with a massive 5/8” (.625”) stainless steel shaft with unmatched sealing strength, Precision fit TPS engagement that is compatible with either Ford or Motec TPS sensor, accompanied by a more versatile two way adjustable linkage system. Also, introducing a unique tapered blade; designed to enhance air-flow and strength. The same 5” V-Band inlet and outlet makes the 123mm HB a direct replacement to our original 123mm throttle body.

Wilson Manifolds High Flow Throttle Bodies were developed using the latest computer modeling software and test equipment available to produce designs that yield the maximum flow per square inch of cross-sectional area. This results in maximum power for any given throttle body type and size. Four barrel style throttle bodies are designed to work with our line of billet spacers and incorporate a tapered and radiused throttle bore and precisely machined progressive linkage for smooth throttle operation. They also feature inward opening throttle blades to eliminate any part throttle directional influence by the blades that can cause poor air distribution. We have also redesigned our Dominator style throttle bodies to incorporate improved throttle linkage and to significantly reduce overall mass. All throttle bodies feature stainless throttle blades to control vibration and reduce thermal expansion Throttle blades are fastened to the throttle shaft using aircraft quality hardware that is both Loctited and peened to assure positive retention of the blades. Throttle shafts are machined to decrease their cross-sectional area, which increases the actual cross-section available for airflow. All throttle bodies are machined from billet 6061-T6 aluminum on precision CNC machining centers for consistent quality and light weight. High flow throttle bodies are available in 4500 and 4150 four-barrel styles as well as many single bore sizes in Ford style.

Throttle Body, 1287 CFM, 4150 Flange, 4-Barrel, Aluminum, Black Anodized, Universal, Each

Throttle Body, 1745 CFM, Dominator Flange, 4-Barrel, Aluminum, Black Anodized, Universal, Kit

Intake Elbow, V-Band Flange Throttle Body, Aluminum, Black, Dominator Flange, Each

Wilson Manifolds open spacers have become the standard in NASCAR NEXTEL Cup racing, but are for use in any application where a top quality light-weight billet spacer is desired. Open spacers increase plenum volume and move the throttle blades away from the roof of the runners, allowing the air/fuel mixture to turn more easily into the runners for improved distribution and mixture quality. Open spacers will add mid range and top end hp. Wilson Manifolds is the only manufacturer to produce open spacers in thicknesses from 1" to 2" in 1/8" increments for 4150 carburetors for precise tuning and for applications where hood clearance is at a premium. The engine builder spacer kit includes all nine open spacers (4150) in 1/8" increments and is a must have for any dyno room and for track tuning. * Adds mid & top end power * Increase plenum volume * Allows the air/fuel mixture to turn more easily into the runners by moving the carburetor up away from the runner roofline * Improved distribution and mixture quality * Will add mid range and top end hp * 1" to 2" Heights in 1/8" increments for 4150 carburetors * Wilson Manifolds is the only manufacturer that offers multiple heights for 4500 carburetors

Wilson Manifolds open spacers have become the standard in NASCAR NEXTEL Cup racing, but are for use in any application where a top quality light-weight billet spacer is desired. Open spacers increase plenum volume and move the throttle blades away from the roof of the runners, allowing the air/fuel mixture to turn more easily into the runners for improved distribution and mixture quality. Open spacers will add mid range and top end hp. Wilson Manifolds is the only manufacturer to produce open spacers in thicknesses from 1" to 2" in 1/8" increments for 4150 carburetors for precise tuning and for applications where hood clearance is at a premium. The engine builder spacer kit includes all nine open spacers (4150) in 1/8" increments and is a must have for any dyno room and for track tuning. * Adds mid & top end power * Increase plenum volume * Allows the air/fuel mixture to turn more easily into the runners by moving the carburetor up away from the runner roofline * Improved distribution and mixture quality * Will add mid range and top end hp * 1" to 2" Heights in 1/8" increments for 4150 carburetors * Wilson Manifolds is the only manufacturer that offers multiple heights for 4500 carburetors * 4150 spacers are designed to pass NASCAR No-Go Gauges

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Intake Elbow, 90-105 mm Throttle Body, Aluminum, Black Anodized, Dominator Flange, Each

Carburetor Spacer, Tapered Lightweight, 1-1/2 in Thick, 4 Hole, Square Bore, Aluminum, Black Anodized, Each

Carburetor Spacer, Tapered Lightweight, 2 in Thick, 4 Hole, Square Bore, Aluminum, Black Anodized, Each

V-Band kit comes with to V-Band clamps with 2- O rings and 5" Male Flange Black Powder Coated Wilson Manifolds High Flow Throttle Bodies were developed using the latest computer modeling software and test equipment available to produce designs that yield the maximum flow per square inch of cross-sectional area. This results in maximum power for any given throttle body type and size. All throttle bodies feature brass throttle blades to control vibration and reduce thermal expansion Throttle blades are fastened to the throttle shaft using aircraft quality hardware that is both Loctited and peened to assure positive retention of the blades. Throttle shafts are machined to decrease their cross-sectional area, which increases the actual cross-section available for airflow. All throttle bodies are machined from billet 6061-T6 aluminum on precision CNC machining centers for consistent quality and light weight. These

Carburetor Spacer, Lightweight, 1 in Thick, Open, Square Bore, Aluminum, Black Anodized, Each

Carburetor Spacer, Tapered Lightweight, 1 in Thick, 4 Hole, Square Bore, Aluminum, Black Anodized, Each

The dual seal connector is designed to secure turbo or supercharger tubing together while still allowing movement to prevent cracked pipes due to chassis flex. This 4" dual seal clamp kit is made to work with our 105mm dual seal throttle bodies (#471105D and #471105DHB and #471090DHB). This kit includes two 4" dual seal clam shells, an aluminum flange, containment ring, ring pin, slic pin, and two o-rings.

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible

Wilson Manifolds Tapered Spacers feature a computer generated variable radius taper design that maximizes the airflow through the carburetor and enhances air/fuel distribution for more horsepower. Part throttle performance and distribution are improved by redirecting the flow pattern created by the partially open throttle blades and gradually reducing the velocity of the air/fuel mixture entering the plenum to allow for a smoother transition into each runner; full throttle performance is improved by increased flow. Our Tapered spacers can increase flow through the carburetor/throttle body by as much as 110 CFM. Wilson Manifolds tapered spacers will increase torque, horsepower and acceleration throughout the entire RPM range. We offer the most complete line of 4-Hole Tapered spacers in 390, 4150, 4500, Q-Jet & 2bbl adapters to provide the high performance consumer with the ability to tune their engine for the maximum performance for any application. Wilson Manifolds is the only manufacturer to offer a choice of tapered spacer heights and produces the only fully CNC machined billet tapered spacer on the market. Wilson Manifolds Tapered spacers will benefit any vehicle that operates under both part and full throttle conditions such as bracket racing using a throttle stop, drag racing, circle track, road racing, off shore power boats, street/strip engines and towing vehicles. * Up To 30+ Bolt On Horsepower * Improves Throttle Response * Improves Distribution * Increases Signal To The Carburetor * Increases Flow Through The Carburetor / Throttle Body * Oval, Drag, Street, Marine & Towing * Works Through The Entire RPM Range * Light Weight Design * Over 30 Years Experience Making Tapered Spacers * Alcohol Compatible