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Manley 11809-8 Severe Duty Stainless Steel Exhaust Valves 1.940 in. Diameter Set of 8

(2019-2023 BMW Z4)

Manufacturer

Picture for manufacturer Manley

Part Number

11809-8
4 reviews
Sale Price

$301.07

2 left at this price

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Product Details

The Manley 11809-8 Severe Duty Series stainless steel exhaust valves are engineered for high-performance and racing engines demanding superior durability and flow characteristics. This set of 8 exhaust valves features precision machining and premium materials for reliable operation under extreme conditions.

Key Features:

  • Constructed from XH-428 stainless steel for exceptional heat resistance and longevity
  • 1.940 inch head diameter optimized for improved exhaust flow
  • 0.342 inch stem diameter with chrome finish for reduced friction and wear
  • 5.522 inch overall length designed for Small Block Chevy applications
  • Hardened valve tips resist damage from rocker arm contact
  • Fully machined and swirl polished for superior surface finish
  • Available with undercut Pro Flo stems or straight stems for optimized flow

Manley's Severe Duty series represents their signature product line in the performance and racing industry, combining superior materials with meticulous manufacturing processes. These valves deliver the reliability and performance demanded by professional engine builders and serious enthusiasts alike.

Products specifications

Fits

2019-2023 BMW Z4

Approximate Weight (g)

127

Lock Groove Quantity

1-groove

Lock Groove Style

Conventional

Overall Valve Length (in)

5.522 in.

Overall Valve Length (mm)

140.289mm

Quantity

Sold as a set of 8.

Swirl-Polished

Yes

Undercut Stem

No

Valve Head Diameter (in)

1.940 in.

Valve Head Diameter (mm)

49.276mm

Valve Head Style

7 degree dish

Valve Material

XH-428 stainless steel

Valve Seat Width (in)

0.100 in.

Valve Stem Diameter (in)

0.342 in.

Valve Stem Diameter (mm)

8.687mm

Valve Tip Length (in)

0.250 in.

Valve Tip Length (mm)

6.350mm

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