-25%
Manley Performance Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)
Manley Performance Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)
Manley Performance Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)
Manley Performance Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)
Manley Performance Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)
Manley Performance Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)
Click to zoom in

Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)

MAN12349-8
807298086057
Valves
5 Units In Stock - Ships Next Business Day
$ 685.44 $ 514.08
$ 514.08

SKU: 12349-8 | UPC: 807298086057

Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8) 1969-1982 Small Block Chevy LT1 Heads

Manley Pro Flo exhaust valves deliver high-flow performance for Chevy Small Block LT1 cylinder heads found on 1969-1982 Camaro Corvette and other models. This set of 8 valves with 1.590 inch head diameter suits Top Fuel Funny Car drag racers Big Block Chevy marine setups and Small Block Chevy circle track engines with restricted carbs. Engineered with swirl polishing these valves increase exhaust flow while handling extreme duty conditions.

Key Features

  • Swirl Polished Design: Computer controlled process adds 10 percent more exhaust flow compared to standard polished valves for better engine breathing and power
  • Undercut Stem Tip: Proprietary Manley tip design reduces valve guide wear and friction during high RPM operation
  • Stainless Steel Construction: Extreme duty XH-426 stainless steel withstands heat and stress in racing and marine environments
  • Precise Dimensions: 1.590 inch head diameter 4.910 inch length 11/32 inch stem and 0.080 inch margin ensure drop-in fit for LT1 heads
  • Set of Eight: Complete exhaust valve kit covers one V8 engine for full performance upgrade

Product Notes

  • Inspect cylinder head valve seats and guides before installation
  • Apply valve seat compound during break-in for longest life
  • Special order item expect 3-5 business days processing time

Installation Notes

  • Professional installation recommended.
  • Valve job required to match swirl polished profile and margins
  • Compatible with stock LT1 head hardware and aftermarket springs up to 180 lbs seat pressure

This Part Fits

Year Make Model Submodel
1969 Chevrolet Camaro Z28
1970 Chevrolet Camaro Z28
1970-1972 Chevrolet Corvette LT1
1971-1972 Chevrolet Camaro Z28
1963-1982 Chevrolet Small Block LT1 Heads

Why Choose Manley?

  • Trusted by Top Fuel and Funny Car teams for proven racing results
  • Valves built to endure high heat and RPM in competition engines
  • Precision machined in USA for exact tolerances and reliability

Frequently Asked Questions

  • Q: Which cylinder heads are compatible with these valves?
    A: Designed for Chevrolet Small Block LT1 heads casting numbers 336299 487399 or equivalent aftermarket LT1 heads on 1969-1982 engines
  • Q: What material are these valves made from?
    A: High strength XH-426 stainless steel alloy for superior heat resistance and durability in extreme applications
  • Q: What is the warranty on Manley valves?
    A: Limited lifetime warranty against manufacturing defects when installed by certified engine builder

Shipping & Handling

  • Method: UPS Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Protective cardboard box 7 x 4 x 2 inches
  • Weight: 1.1 lbs

Request For Information

Have questions about Manley Chevy LT-1 1.590 Head Diameter Pro Flo Exhaust Valves (Set of 8)? Fill out the form below and we'll get back to you by the next business day.
Manley Performance

Manley Performance

Manley Performance is a New Jersey-founded engine internals manufacturer stocked at Black Ops Auto Works, supplying forged pistons, connecting rods, valves, and crankshafts across domestic and import platforms. Shop Manley H-Beam and H-Tuff connecting rods, Race Master Series valves, forged crankshafts, and valve springs for Ford Modular and Coyote, Chrysler HEMI, Subaru EJ and FA, Nissan SR20 and 2JZ, Honda B and H-series, and Mitsubishi 4B11T and Mazda MZR platforms. Every product is filterable by year, make, model, and engine code so the correct part ships the first time. Black Ops Auto Works carries 270 Manley Performance SKUs across pistons, rotating assembly, and valvetrain components. About Manley Performance Founded in 1966 by Hank Manley as Manley Speed Equipment, Manley Performance has grown into one of the most established names in high-performance engine internals. From grassroots drag racing roots in New Jersey to a second manufacturing facility in Orange, Californi...

View Manley Performance Products
Valves

Valves

Engine valves for import, domestic, and European performance builds are stocked at Black Ops Auto Works. Shop intake valves, exhaust valves, single-groove and triple-groove valves, Inconel and titanium valves, and complete valve sets for 2JZ, RB26, RB25, VR38DETT, K-series, EA888, EA113, FA20, S58, B58, and HEMI 5.4L and 5.7L applications. Every product is filterable by year, make, model, trim, engine, and drivetrain so the correct part ships the first time. Black Ops Auto Works carries 577 valve SKUs across intake, exhaust, and material specification categories. What This Category Covers The Valves category covers replacement and upgraded intake and exhaust valves for naturally aspirated, turbocharged, and supercharged cylinder heads. Coverage spans budget-focused OE-spec valves through race-grade Inconel and titanium valves built for sustained high RPM and boosted horsepower. Categories Included Intake valves, exhaust valves, single valves sold individually, and full valve set...

View Valves Products
Valves & Components

Valves & Components

Valves and valvetrain components for import, domestic, and performance engine platforms are stocked at Black Ops Auto Works. Shop intake valves, exhaust valves, valve covers, valve cover gaskets, valve guides, valve springs, retainers, valve locks, valve seals, and lash caps for Toyota 2JZ and Supra, Honda K-Series, Nissan RB and SR20, BMW B58 and S58, Subaru FA20, Ford Coyote, and GM LS platforms. Every part is filterable by year, make, model, and engine so builders and tuners can confirm fitment before ordering. Black Ops Auto Works carries 1,391 valvetrain SKUs from proven performance brands. What This Category Covers Valves and valvetrain components manage airflow into and out of the combustion chamber and keep the valvetrain sealed and stable at high RPM. This collection spans intake valves, exhaust valves, valve covers, valve cover gaskets, valve guides, valve springs, retainers, valve locks, valve seals, lash caps, and cam follower shims. Why the Valvetrain Matters for Pe...

View Valves & Components Products
Military & First Responder Discounts

Military & First Responder Discount Program

Black Ops Auto Works proudly honors active duty military, veterans, National Guard, reserves, police officers, firefighters, and EMTs with an exclusive 5% discount on all performance parts and carbon fiber upgrades. Verify instantly and start saving today.

Learn More & Apply

Your cart

×