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Cylinder Heads - Aluminum (6)
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Cylinder Heads - Cast Iron (2)
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Cylinder Heads - Cast Iron
SD Performance spends an extensive amount of time on the dyno, at the track and on the street to develop some of the best performing Pontiac ported cylinder heads on the market today. SD Performance is the first head porting business to offer ultra precise 5 Axis CNC ported Cast Iron Heads for Pontiacs. All of our heads are flow tested on our state of the art computerized Superflow 600 flowbench equipped with velocity probes, but we’ve learned that what really counts, is how our heads work in the real world. A flowbench is a great tool which we use daily, but there is more to an efficient head than just flow, too many put their faith in flowbench numbers alone.

Note: SD Peformance has a large inventory of Pontiac cylinder head castings in stock, give us a call if you are looking for something specific, we can apply all the below packages to any Pontiac head casting. (flow numbers will vary on different castings) Give us a call or shoot us an e-mail for more details, we are here to help you make the best choice to meet your specific needs.

Do you have a set of RAII,RAIV,RAV,455HO, SD455 heads that you need to be prepped? Give us a call, we've done them all!

All Cast iron heads include: (Unless stated otherwise)

  • New Flanged Full Bronze guides installed and sized to exact tolerances

  • High Flowing 4 angle intake seats, cut on our state of the art Rottler SG8 seat and guide machine

  • High Flowing 4 Angle exhaust seats when converting to 1.77” valves or 3 angle on factory 1.77” valve heads or 4 when hardened seats are installed

  • Now included in all iron head packages!!! Deck, Intake and exhaust flanges!!! are Ultra Precisely CNC Machined with 12" CBN cutter head for the ultimate finish and gasket seal

  • Ferrea 5000 series stainless steel valves

  • New springs good to at least .600” lift for hyd. or solid cams

  • Spring seats machined to postively locate the bottom of the springs, depending on the application cups or locators may be used

  • Positive Viton seals on intake and exhaust

  • 10 deg Chrome Moly retainers with machined locks

  • New heater nipple

  • New Freeze plugs

  • ARP 7/16 studs**

  • Precision assembly*

    *SD Performance precision assembly means, we test ALL valve springs on a digital spring tester, and set ALL installed heights individually to equalize the springs as close as possible.

** Please note: There is an additional $150.00 charge to convert cylinder heads that have press in studs to screw in studs. We can also drill and tap missing exhaust bolt holes for $5.00 each

*** Note: Core charges will vary, depending on casting number.

Hardened Exh. Seats add $15.00 per seat to any of our head packages, ONLY $120.00 extra on a pair of heads, give us a call for more details and recommendations

CNC Ported 230-240cfm 389/421 Heads
CNC Ported 389/421 Head Packages!!

Intake ports are fully CNC ported to flow 230-240cfm @ .550" lift with hand blended bowls and short turns on the exhaust ports to achieve 70+% exhaust to intake flow ratio. Hardened exhaust seats, Full bronze guides, spring cups, chrome-moly retainers, Comp 995 springs, and Stainless 1.940" and 1.650" valves are installed. Conversion to 7/16" screw in studs is available at an extra charge.

Complete ready to bolt on packages starting at $1695.00US using your cleaned and magnafluxed cores. Call or e-mail for more details. Our customers asked for it and we delivered another great power building head package for those wanting to retain their 389/421 heads while also wanting to produce a lot more power over stock heads!!!

Note: with the 7/16" rocker stud conversion you can run PRW stainless rockers with short nuts under the stock 389 valve covers!!

Programs available for 1963/64 #716, 1965 #76,77 1966 #092,093,094

Additonal Options for above heads

  • Cleaning + magnafluxing your cores $100 per pair

  • Fill exhaust crossovers with aluminum add $100.00

  • Convert to ARP 7/16" screw in studs add $195.00

  • Custom guide plates for heads with worn pushrod slots add $100.00

$ 1695.00

$ 2305.20

CNC Ported 255-265cfm D-port cast iron heads
CNC Street port D-port heads (available for 670, 16, 62, 46, 47, 48, 11, 12, 13, 17, 18, 96, 7K3, 4X, 5C, 6X and other castings). Includes everything above, plus fully CNC ported 255+ cfm @ .600” lift @ 28” intake ports, fully CNC ported exhaust ports, valve springs setup for either flat tappet or hyd. roller cams, positively located spring seats for increased spring stability and longevity, ARP 7/16” rocker studs, pushrod holes notched for 1.65 rockers, flow chart included. Complete ready to bolt on package using customers cleaned and magnafluxed cores from $1795.00 or complete package including SD supplied cores starting from $2095.00 (core charges vary with casting numbers - please call for availability and pricing)
Most mild street applications will experience an easy 50+hp gain over stock heads and even more with more aggressive combo's!!!

Additonal Options for above heads

  • Cleaning + magnafluxing your cores $100 per pair

  • Fill exhaust crossovers with aluminum add $100.00 per pair

  • Hardened exhaust seats machined and installed add $120.00 per pair

For more details or questions e-mail us at techsupport

$ 1795.00

$ 2441.20

  * SD Performance reserves the right to change prices without notification.  
  * Canadian customers, please add GST. BC customers, please add GST and PST