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ProMaxx Performance 2151

Cast Iron Small Block Chevy Vortec Cylinder Heads Assembled

ProMaxx Performance 2151


ProMaxx Performance 2151 Cast Iron Small Block Chevy Vortec Cylinder Heads Assembled $764.99
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Estimated to ship directly from the manufacturer on 05/30/18
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Chevrolet Performance SBC Cast Iron Vortec Cylinder Head 170cc Intake Ports
Chevrolet Performance 809-12558060
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Cast Iron Small Block Chevy Vortec Cylinder Heads
  • Assembled
  • Straight Plug
  • Intake Ports: 185cc
  • Combustion Chambers: 64cc
  • Valves: 2.02" Intake, 1.60" Exhaust
  • Hyd. Flat Tappet Springs
  • Pair

  • Specifications:

    Accessory Bolt Holes Drilled
    CNC-Machined Combustion Chamber
    CNC-Machined Exhaust Runner
    CNC-Machined Intake Runner
    Combustion Chamber Volume (cc)
    Cylinder Head Finish
    Cylinder Head Material
    Cast iron
    Cylinder Head Style
    Damper Spring Included
    Exhaust Port Location
    Exhaust Port Shape
    Exhaust Runner Volume (cc)
    Exhaust Valve Diameter (in.)
    Exhaust Valves Included
    Guideplates Included
    Heat Crossover
    Intake Port Location
    Intake Runner Volume (cc)
    Intake Valve Diameter (in.)
    Intake Valves Included
    Lock Style
    Locks Included
    Machined for O-Ring
    Maximum Valve Lift (in.)
    Oiling Style
    Through pushrod
    Outside Diameter of Outer Spring (in.)
    Sold as a pair
    Retainer Material
    Retainers Included
    Rocker Arm Nuts Included
    Rocker Arm Studs Included
    Rocker Arms Included
    Spark Plug Style
    Steam Holes Drilled
    Valve Cover Mounting Style
    Center and perimeter bolt
    Valve Guide Material
    Manganese bronze
    Valve Guides Included
    Valve Seat Machine Style
    Valve Seat Material
    Ductile iron
    Valve Seats Machined
    Valve Springs Included
    Valve Stem Seals Included
    Manufacturer's Part Number:

    Manufactured from cast iron, ProMaxx Performance Small Block Chevy Vortec 185cc Cylinder Heads include 2.02" intake/1.60" exhaust valves, valve springs with .575" max lift for hydraulic flat tappet camshafts or .500" max lift for hydraulic roller camshafts, 3/8" screw-in studs, and guideplates.

  • All New Parts and Castings
  • Accepts Center Bolt or Perimeter Bolt Valve Covers
  • Drilled for Vortec and Carbureted Intake Patterns
  • Large Diameter Spring Pockets
  • Perfect for Street, Strip, or Oval Track Applications
  • Stainless Steel Valves
  • Screw-In Studs and Guideplates
  • Sold In Pairs

    JEGS Easy Kits are designed by JEGS professionals so you get all the parts you need.

  • 2151 - ProMaxx Performance Small Block Chevy Vortec Cylinder Heads is rated 2.8 out of 5 by 4.
    Rated 5 out of 5 by from Race Winning Heads - Great Affordable HP Bolted these on with a Jegs Vortec intake and immediately gained a tenth in the 1/4 in a 91 RS Camaro running a stock re-manufactured 350 with a Comp Cams HR cam and Magnum roller rockers and Magnum push rods. Over 125 runs in as of this posting and the heads performed like new. This is great HP for the money. And these can carry over to the next build.
    Date published: 2017-12-08
    Rated 3 out of 5 by from Stock center bolt valve covers would not work Got these heads couple of months ago very nice screw in studs guide plates stainless steel 5 cut valves 202 and160 the only problem the stock center bolt valve covers would not fit they hit on the guide plates which was a problem on the 99 suburban
    Date published: 2014-12-25
    Rated 2 out of 5 by from Promax heads vortec iron Both heads had valve seat problems 3 on one head 2 on the other all on exhaust side assembled heads . (But not bolt on) ( bad build quality)
    Date published: 2015-02-16
    Rated 1 out of 5 by from Don't buy! I purchased these heads for my 50 Chevy pickup engine build. I have to admit they looked great when I took them out of the box. My engine build went on hold for two years so the 3 month warranty was down the toilet before I installed them on my finished short block. I air checked them for valve seal and found that all 8 intake valves were leaking heavily thru the intake port. Disassembly revealed issues with seat height, all the valve guides so tight you had to tap the valves out especially on the exhaust side and after several attempts to seal one intake valve, we found that the leak was caused by a poorly installed intake seat. When the seat was tapped, it fell out. Same thing happened when the seat in the next cylinder was tapped. It fell out also. I'm having all the intake seats replaced now and will have to redo the valve job and hand ream the guides to get proper clearance. Why would it be necessary to install intake seats in a new set of cast iron heads? Poor castings? Oh yea, I forgot to mention that the valve seating area was not concentric. the seat width was thin on one side the thick on the other. If the engine had been fired up and been run thru the cam break in process, I'm sure the end result would have been catastrophic engine failure due to stuck valves and dropped intake seats. I'm lucky because I didn't have to troubleshoot these issues with the engine in the vehicle. Save yourself a lot of grief and purchase a different brand.
    Date published: 2018-03-16
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    Will p/n 2151 work with Edelbrock Performer intake manifold for pre-'86 SBC? Or would it be better to buy a new Performer manifold for Vortec heads? What p/n springs can you recommend for hyd roller cams? Thank you.

    Asked by: VolvoTech
    The manifold will not line up and seal properly with these heads. Depending on the cam lift and machine work you do to the heads you can use Comp Cam #986-16
    Answered by: Dean R
    Date published: 2018-01-18

    I tried using a 1205 gasket and a team g intake the intake and gaskets don't cover the top of the intake runner there is a 1/6"gap at the top of the runner but a vortec intake covers the runner

    Asked by: Choper
    A vortec intake covers the runner because they're vortec heads. Please contact a technical representative so we can get more information on the engine and help from there. 1.800.345.4545
    Answered by: Dean R
    Date published: 2018-01-13

    What plugs should be used? Can Bosch 4458 be used? If not what bosch platinum plus 4 plugs should be used?

    Asked by: jweeks
    The recommended plug is a 739-R56737, but a Bosch 4458 should work for this cylinder head also.
    Answered by: Rusty B
    Date published: 2018-01-14

    If I change the springs can I run hydraulic roller?

    Asked by: Jaybird1
    A hydraulic roller can be used with a spring change.
    Answered by: Jon Jegs Tech
    Date published: 2017-12-01

    Do these heads have the GM part #’s on them, or are they copies of the Vortec heads?

    Asked by: Inline69
    These do not have GM part numbers on them. They are an aftermarket head.
    Answered by: Jon Jegs Tech
    Date published: 2017-11-30

    Do you need to run self aligning rocker arms?

    Asked by: 87trans
    You should run self aligning rocker arms with this cylinder head.
    Answered by: Rusty B
    Date published: 2017-09-06
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