Product Summary

305, 350, .375" Overall Thickness, Gasket(s) Included

  • Bolts to centerbolt heads allowing user to use standard valve covers and stud girdles
  • O-ring seal on head side
  • Use standard gaskets on valve cover side
  • Compatible with '60-'86 "straight bolt" & '55-'59 staggered bolt valve covers
  • Will not work with aluminum roller rocker arms

Key Specs

MFG. Part #91017157
BrandSpeedway Motors

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Speedway Motors 91017157 Details

As you know, you can't run a stud girdle when using centerbolt valve covers. These handy adaptors simply bolt to your centerbolt heads which allows you to use standard valve covers and stud girdles. O-ring seal on head side. Use standard gasket on valve cover side. Has bolt holes to use with early '60-'86 "straight bolt" valve covers as well as '55-'59 staggered bolt valve covers.

Will not work with aluminum roller rocker arms.

CARB Warning

For race/ off road use or for use on pre-1966 vehicles.

Emissions warning: this part only legal for sale or use in California for racing (competition) vehicles which may never be used, registered, or licensed for use upon a public highway, or if installed in vehicles model-year 1965 or older; motorcycles model-year 1977 or older; or off-highway recreational vehicles (such as off-road motorcycles and all-terrain vehicles) model-year 1996 and older. Any other use renders the vehicle tampered and not legal for use on California public highways (any public street or roadway, public dirt road, public park, or publicly maintained right of way open to the use of the public for vehicular travel). Violations subject to $37,500 penalty per violation per vehicle, revocation of registration, loss of use on California public right of ways, and proof of correction for tampering. There are similar restrictions and penalties under federal law and the laws of all other states with penalties under federal law of up to approximately $45,268 per tampered vehicle and/or engine.

Speedway Motors 91017157 Specifications

MFG. Part #91017157
BrandSpeedway Motors
Overall Thickness.375"
Gasket(s) IncludedYes
Hardware IncludedYes
Material TypeAluminum
Sold in QuantityPair
NotesMade to mount "perimeter" style valve covers on '86-newer heads.