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Manley 12843-8 Severe Duty Exhaust Valves Big Block Chevy 1.880" Head Diameter

Manufacturer

Picture for manufacturer Manley

Part Number

12843-8
8 reviews
Sale Price

$301.07

4 left at this price

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Usually delivered within 2 days

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Product Details

The Manley 12843-8 Severe Duty exhaust valve set is engineered for high-performance Big Block Chevy applications. This 8-valve set features 1.880" head diameter exhaust valves crafted from premium XH-428 stainless steel, a material exclusive to Manley that delivers exceptional strength and durability in extreme operating conditions.

Key Specifications:

  • Head Diameter: 1.880 inches
  • Stem Diameter: 5/16" (0.3110")
  • Overall Length: 5.422 inches
  • Tip Length: 0.250 inches
  • Installed Height: Stock
  • Underhead Angle/Radius: 12° x 3/8"
  • Margin: 0.075 inches
  • Seat Width: 0.100 inches
  • Top of Head: 7° Dish
  • Weight: 107 grams per valve

Premium Features:

  • XH-428 stainless steel construction with nearly double the tensile strength at 1500°F compared to competitive materials
  • Chrome stems and hardened valve tips for superior wear resistance
  • Swirl polished under head areas for optimized airflow
  • Fully machined combustion faces for improved efficiency
  • Proven to endure up to 100 million cycles in rigorous fatigue testing at 40,000 psi and 1400°F

Important Note: These 5/16" stem valves feature Bead Loc keeper grooves and require Bead Loc valve locks (sold separately).

Ideal for bracket racing, oval track competition, and high-performance street engines, Manley Severe Duty valves deliver unmatched reliability and performance for demanding Big Block Chevy builds.

Great so far. I'll know better once I receive and get to use it.

They had the lowest price and great communication. Will order from them again thanks

For as cheap as what I paid for my product I will admit I was scared!!! Got what I asked for in perfect condition, came fast and wonder where have you been all my shopping life? Thanx for such a great deal and fast shipping!!!

Ok so far

Incredible prices! I purchased a name brand leveling kit for 40% less than any one else is selling them for. Item shipped out within 2 days. Shipping cost is reasonable, and if you leave a review here after your purchase, they'll credit you back $5! BEST DEAL GOING!

I looked around for the best peice for a set of Sparco seats. I found them on autoplicity much cheaper then anywhere else. I figured it would take a few days to ship, but by the time i decided to call for a tracking #, I got an email with tracking # and that my seat was all ready to be delivered the next day. They didnt ship together because they were out of stock for a day or 2. I called about my other seat a few days later and it was already delivered at my door. Any future purchases will be checked with autoplicity 1st.

Great site. Provided needed technical specs. Shipped promptly. Although I had to ask for the tacking number, it was not emailed, one was provided promptly upon request.

best price, cheap shipping, easy to order, thank you Order Number: 4829<br>

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