Industrial Hard Seat, 1.625" x 1.312" x .219"

M2 Alloy Valve Seats, set of eight

Application: Universal and SBF application listed below.

    Common application:

•  SB Ford GT40 w/ 1.540" Exhaust
  
• SB Ford 351W w/ 1.540" Diameter Exhaust
• Universal applications with exhaust valves diameter between 1.530"-1.590"
  
• Includes eight seats for the listed price

M2 series valve seats are a step up over high chrome, they offer increased resistance to wear while maintaining integrity to higher temperatures. M2 is a good medium to heavy duty valve seat insert.

M2 offers good machinability, they can be machined by cutting and/or grinding.

     Sizes:

• Outside Diameter: 1.625" Plus Press
  
• Inside Diameter: 1.312"
• Depth" .219"
• Chamfered leading edge for ease of installation
• Suggested press fit for iron head- .0045" - .006"
  

    Material:

• M2 Alloy contains: Carbon, Silicon, Manganese, Chrome, Molybdenum, Nickel, Vanadium and Tungsten

Tech Notes-
  

1.     Intake seats do not need to be changed to run unleaded fuel, only exhaust
2.     Iron heads which came from the factory with seats usually require special size replacement seats.
3.     Aluminum heads also use special size seats. Their depth is usually much deeper then unleaded retro fit seats.
4.     Aluminum heads commonly use depths between .275"-.437"
5.     Propane applications require Hi Nickel / Tungsten Alloy seat. 
6.     Aluminum heads require more press fit then iron.
7.     When going to oversize valves, care in selecting a seat size is important. OE iron heads are cast for smaller valves so there might not be enough wall thickness to install the typical seat size used for a oversize valve. Normally, a unique OD seat is required. Under these circumstances, a seat is selected with a .030- .050" bigger OD then the valve. This is normally done by a shop using adjustable seat cutters. (check around) Some seat manufacturers offer oversize OD seats in: +.010", .020", .030", .040" etc. In the case of a BBC w/ 1.880" exhaust, they would select a 1.875" seat +.040" which would be .035" bigger then the valve. Going bigger puts the casting at risk of breaking into the water jacket. Each head brand and model is different. Some castings are thicker then others. Consult your machinist for which heads will accept oversize seats and which ones won't.