• 1987-1991 Corvette (Centerbolt Valve Covers)
• Springs for Hydraulic Flat Tappet Camshaft
• Port Volumes: 165cc/65cc
• Valve Size: 2.02"/1.60"
• 60cc Combustion Chamber
• Assembled, Sold Individually
  
  Designed for 1986-91 Tuned Port Injected (T.P.I) 5.7L small-block Chevy Corvette engines originally equipped with centerbolt valve covers. Performer centerbolt cylinder heads are 50-state street legal and accept factory centerbolt valve covers. The intake bolt pattern utilizes the 1986-91 (straight) 90° angle on all bolts. Spark plugs are angled like stock O.E. heads.
  
  

  Combustion Chamber Volume:	60cc
  Intake Runner Volume:	165cc
  Exhaust Runner Volume:	65cc
  Intake Valve Diameter:	2.02'
  Exhaust Valve Diameter:	1.60'
  Valve Stem Diameter:	11/32'
  Valve Guides:	Manganese Bronze
  Deck Thickness:	5/8'
  Valve Spring Diameter:	1.46'
  Valve Spring Maximum Lift:	0.575'
  Rocker Stud:	3/8'
  Guideplate:	Hardened Steel
  Pushrod Diameter:	5/16'
  Valve Angle:	23°
  Exhaust Port Location:	Stock
  Spark Plug Fitment:	14mm x 3/4' Reach, Gasket Seat

  
  
  

  Valve Lift	Intake	Exhaust
  .100'	64	54
  .200'	122	96
  .300'	177	124
  .400'	217	147
  .500'	229	166
  .600'	232	175
  .700'	N/A	N/A
  Flow Numbers as tested by Edelbrock's SuperFlo SF-1020 flow bench @ 28' H2O

  
  
  Technical Notes: Recommended spark plugs are Champion RC12YC or equivalent 14mm x 3/4" reach with flat gasket seat.

Emissions Note:

This part is legal for sale and use on Emissions Controlled Vehicles, in all 50 states, when used in accordance with the manufacturer's application guide because it has a California Air Resources Board (CARB) Executive Order (EO) # D-215-94

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