Header Flanges, Gaskets

 Finished & Plain Header Flanges, Gaskets.

 
     
 
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FORD - Finished Header Flanges, Plain Header Flanges, Header Flanges with formed Starter Tubes, Header Gaskets

Engine Series:

  
 
There are quite a few header flange designs to pick from on this page.  In fact, so many choices that the selection process might be confusing and may be even disturbing. Don't worry about this.  Once you figure out the basics of what you want to accomplish and are ready to place an order, we'll help you select the best header flange design for your headers. 
 
 
Header Flanges
1 3/4" OD Finished Header Flanges
Dart/World Products, etc. Windsor Ford Cylinder heads
with the "spread" (3" center-to-center) bolt hole pattern.
 (Part Number 20625E38.)  Also available with 1 1/2", 1 5/8" and 1 7/8" OD
starter tubes and flange thicknesses of 1/4", 5/16", and 3/8".
    
Header Flanges
1 1/2" OD Finished Header Flanges
4.6 liter SOHC Ford V8.
 (Part Number 20680C38.)  Also available with 1 3/8" and 1 5/8" OD
starter tubes and flange thicknesses of 1/4", 5/16", and 3/8".
    
Header Flanges
1 1/2" ID Plain Header Flanges
4.6 liter SOHC Ford V8.
 (Part Number 25680C38.)  Also available with 1 3/8" and 1 5/8" ID ports
and flange thicknesses of 1/4", 5/16", and 3/8".
    

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Header Kits Finished
Header Flanges		 Plain
Header Flanges		 Header Flanges w/Starter Tubes Header Gaskets Notes Note
Explanations.

(Look at the bottom
HEADER FLANGE COMMENTS
area for more
information.)
Engine Description -
Cubic Inch Range
Flange Port Size1, Description 		Part
Number 		Price2,3 Part
Number		 Price2 Part
Number		 Price2,3 Part
Number		 Price
Photo? Photo? Flange Design Comments
 FLATHEAD V8 123456789A123456789B123 123456789A123456789B12    
 32-53 Ford
 221-239-255"
 1 3/8", 1 7/8" Round		 20600BF $284.002 25600BF $146.952 22600BF $186.902 See Notes ------ 9,9.5 See Note 9.5.
Use 6 of #60D22 Tube Flange Gasket.
    Center Port is larger than end ports.
 32-53 Ford
 221-239-255"
 1 1/2", 2" Round		 20600CG $284.002 25600CG $146.952 22600CG $186.902 See Notes ------ 9,9.5 See Note 9.5.
Use 6 of #60D22 Tube Flange Gasket.
    Center Port is larger than end ports.
 32-53 Ford
 221-239-255"
 1 1/2", 2 1/8" Round		 20600CH $284.002 25600CH $146.952 22600CH $186.902 See Notes ------ 9,9.5 See Note 9.5.
Use 6 of #60D22 Tube Flange Gasket.
    Center Port is larger than end ports.
 32-53 Ford
 221-239-255"
 1 5/8", 2 1/4" Round		 20600DJ $284.002 25600DJ $146.952 22600DJ $186.902 See Notes ------ 9,9.5 See Note 9.5.
Use 6 of #60D22 Tube Flange Gasket.
    Center Port is larger than end ports.
 32-53 Ford
 221-239-255"
 1 3/8", Round		 20600B $284.002 25600B $146.952 22600B $186.90 See Notes ------ 9,9.5 Use 6 of #60D22 Tube Flange Gasket.
    Ports in flange are all the same size.
 32-53 Ford
 221-239-255"
 1 1/2", Round		 20600C $284.002 25600C $146.952 22600C $186.90 See Notes ------ 9,9.5 Use 6 of #60D22 Tube Flange Gasket.
    Ports in flange are all the same size.
 32-53 Ford
 221-239-255"
 1 5/8", Round		 20600D $284.002 25600D $146.952 22600D $186.90 See Notes ------ 9,9.5 Use 6 of #60D22 Tube Flange Gasket.
   Header Flange Ports in flange are all the same size.
 32-53 Ford
 221-239-255"
 1 3/4", Round		 20600E $284.002 25600E $146.952 22600E $186.90 See Notes ------ 9,9.5 Use 6 of #60D22 Tube Flange Gasket.
  Header Flange Ports in flange are all the same size.
 32-53 Ford
 221-239-255"
 1 7/8", Round		 20600F $284.002 25600F $146.952 22600F $186.90 See Notes ------ 9,9.5 Use 6 of #60D22 Tube Flange Gasket.
    Ports in flange are all the same size.
 37-40 Ford (V8-60)
 136"
 1 1/4" Round		 20601A $284.002 20601A $146.952 22601A $186.902 See Notes ------ 9  
    Ports in flange are all the same size.
 Turnpike Cruiser   123456789A123456789B123456789C1234567 123456789A12345678
 52-57 Ford
 279-317-341-368" 
 1 3/4", Round		 20603E $290.502 25603E $146.952 22603E $186.90 ------ ------    
     
 "Y"- Block   123456789A123456789B123456789C1234567 123456789A12345678
 54-62 Ford
 239-272-292-312"
 1 1/2", Round		 20604C $290.502 25604C $146.952 22604C $186.902 28604 $16.65    
     Finished Header Flanges with larger ports - add $24.00.
 54-62 Ford
 239-272-292-312"
 1 5/8", Round		 20604D $290.502 25604D $146.952 22604D $186.902 28604 $16.65    
     
 54-62 Ford
 239-272-292-312"
 1 1/2", Rectangular		 20605C $314.502 25605C $146.952 22605C $186.902 28605 $24.35    
     
 54-62 Ford
 239-272-292-312"
 1 5/8", Rectangular		 20605D $314.502 25605D $146.952 22605D $186.902 28605 $24.35    
     
 Lincoln, Edsel, Mercury, etc.   123456789A123456789B123456789C1234567 123456789A12345678
 58-68 Lincoln, etc.,
 383-410-430-462"
 1 7/8", Rectangular		 20606F $309.502 25606F $146.952 ------ ------ ------ ------   No Header Bolts needed due to head design.
     No Header Bolts w/Finished Header Flanges
 58-68 Lincoln, etc.,
 383-410-430-462"
 2", Rectangular		 20606G $309.502 25606G $146.952 ------ ------ ------ ------   No Header Bolts needed due to head design.
     No Header Bolts w/Finished Header Flanges
 FE Engine Series (332-352-360-390-406-427-428")   123456789A123456789B123456789C1234567 123456789A12345678
 58-70 Ford
 332-428"
 1 5/8", Rectangular		 20610D $314.502 25610D $146.952 ------ ------ 28610 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
     
 58-70 Ford
 332-428"
 1 3/4", Rectangular		 20610E $314.502 25610E $146.952 ------ ------ 28610 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
     
 58-70 Ford
 332-428"
 1 7/8", Rectangular		 20610F $314.502 25610F $146.952 ------ ------ 28610 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
     
 58-70 Ford
 332-428"
 2", Rectangular		 20610D $314.502 25610D $146.952 ------ ------ 28610 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
     
 58-70 Ford
 332-428"
 1 7/8", Rectangular		 20611F $314.502 25611F $146.952 ------ ------ 28611 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
    Ports are 1/4" taller than 610 series flanges.
 58-70 Ford
 332-428"
 2", Rectangular		 20611G $314.502 25611G $146.952 22611G $186.90 28611 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
    Ports are 1/4" taller than 610 series flanges.
 58-70 Ford
 332-428"
 2 1/8", Rectangular		 20611H $314.502 25611H $146.952 ------ ------ 28611 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
    Ports are 1/4" taller than 610 series flanges.
 58-70 Ford
 332-428"
 2 1/4", Rectangular		 20611J $314.502 25611J $146.952 ------ ------ 28611 $17.55   8 Bolt Exhaust Pattern.  Bolt holes above and below each port.
    Ports are 1/4" taller than 610 series flanges.
 58-70 Ford
 332-428"
 See Notes, Rectangular		 ------ ------ 25610E $92.95 ------ ------ 28610 $17.55   8 Bolt Exhaust Pattern.  8 individual plates.  1 1/2" x 2" tall port.
    8 individual plates.  Can be used with 1 3/4" or 1 7/8" tubes.
 58-70 Ford
 332-428"
 See Notes, Rectangular		 ------ ------ 25616E $104.90 ------ ------ 28610 $17.55   8 Bolt Exhaust Pattern.  4 individual plates.  1 1/2" x 2" tall port.
    4 plates w/2 ports per plate. Use with 1 3/4" or 1 7/8" tubes.
 66-70 Ford
 390-428"
 1 5/8", Rectangular		 20613D $322.502 25613D $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern.
     
 66-70 Ford
 390-428"
 1 3/4", Rectangular		 20613E $322.502 25613E $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern.
     
 66-70 Ford
 390-428"
 1 7/8", Rectangular		 20613F $322.502 25613F $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern.
     
 66-70 Ford
 390-428"
 2", Rectangular		 20613G $322.502 25613G $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern.
     
 66-70 Ford
 390-428"
 2 1/8", Rectangular		 20613H $322.502 25613H $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern.
     
 58-70 Ford
 390-428"
 1 5/8", Rectangular		 20617D $330.50 25617D $168.40 ------ ------ 28617 $17.55   14 Bolt Exhaust Pattern.
     
 58-70 Ford
 390-428"
 1 3/4", Rectangular		 20617E $330.50 25617E $168.40 ------ ------ 28617 $17.55   14 Bolt Exhaust Pattern.
     
 58-70 Ford
 390-428"
 1 7/8", Rectangular		 20617F $330.50 25617F $168.40 ------ ------ 28617 $17.55   14 Bolt Exhaust Pattern.
     
 58-70 Ford
 390-428"
 2", Rectangular		 20617G $330.50 25617G $168.40 ------ ------ 28617 $17.55   14 Bolt Exhaust Pattern.
     
 58-70 Ford 332-428"
 Edelbrock brand
 1 5/8", Rectangular		 20618E $322.502 25618D $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern. Port floor is higher than original 428 heads.
    Edelbrock brand.  Port floor is higher than factory 428 heads.
 58-70 Ford 332-428"
 Edelbrock brand
 1 3/4", Rectangular		 20618E $322.502 25618E $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern. Port floor is higher than original 428 heads.
    Edelbrock brand.  Port floor is higher than factory 428 heads.
 58-70 Ford 332-428"
 Edelbrock brand
 1 7/8", Rectangular		 20618F $322.502 25618F $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern. Port floor is higher than original 428 heads.
    Edelbrock brand.  Port floor is higher than factory 428 heads.
 58-70 Ford 332-428"
 Edelbrock brand
 2", Rectangular		 20618G $322.502 25618G $155.302 ------ ------ 28613 $17.55   16 Bolt Exhaust Pattern. Port floor is higher than original 428 heads.
    Edelbrock brand.  Port floor is higher than factory 428 heads.
 SOHC   123456789A123456789B123456789C1234567 123456789A12345678
 SOHC Ford
 427"
 2", Round		 20614G $290.502 25614G $146.952 22614G $186.902 28615 $29.35   5 Bolt Exhaust Pattern.
     
 SOHC Ford
 427"
 2 1/8", Round		 20614H $290.502 25614H $146.952 22614H $186.902 28615 $29.35   5 Bolt Exhaust Pattern.
     
 SOHC Ford
 427"
 2 1/4", Round		 20614J $290.502 25614J $146.952 22614J $186.902 28615 $29.35   5 Bolt Exhaust Pattern.
     
 SOHC Ford
 427"
 2", D port		 20615G $314.502 25615G $146.952 ------ ------ 28615 $29.35   5 Bolt Exhaust Pattern.
    Flat area on top of port.
 SOHC Ford
 427"
 2 1/8", D port		 20615H $314.502 25615H $146.952 ------ ------ 28615 $29.35   5 Bolt Exhaust Pattern.
    Flat area on top of port.
 SOHC Ford
 427"
 2 1/4", D port		 20615J $314.502 25615J $146.952 ------ ------ 28615 $29.35   5 Bolt Exhaust Pattern.
    Flat area on top of port.
 Windsor   123456789A123456789B123456789C1234567 123456789A12345678
 62-up Ford
 221-351"
 1 3/8", Rectangular		 20620B $314.502 25620B $146.952 ------ ------ 28620 $15.40   8 Bolt Exhaust Pattern in a horizontal line.
     
 62-up Ford
 221-351"
 1 1/2", Rectangular		 20620C $314.502 25620C $146.952 ------ ------ 28620 $15.40   8 Bolt Exhaust Pattern in a horizontal line.
     
 62-up Ford
 221-351"
 1 5/8", Rectangular		 20620D $314.502 25620D $146.952 ------ ------ 28620 $15.40   8 Bolt Exhaust Pattern in a horizontal line.
     
 62-up Ford
 221-351"
 1 3/4", Rectangular		 20620E $314.502 25620E $146.952 ------ ------ 28620 $15.40   8 Bolt Exhaust Pattern in a horizontal line.
     
 62-up Ford 221-351"
 Trick Flow Specialties
 1 3/4", Rectangular		 20620E $314.502 25620E $146.952 ------ ------ 28620 $15.40   8 Bolt Exhaust Pattern in a horizontal line.
    25620E port size is best match to the TFS "street" head.
 62-up Ford
 221-351"
 1 3/8", Round		 20621B $290.502 25621B $146.952 22621B $186.902 28620 $15.40   Finished port in flange does not match port in head.
     Finished Header Flanges with larger ports - add $24.00.
 62-up Ford
 221-351"
 1 1/2", Round		 20621C $290.502 25621C $146.952 22621C $186.902 28620 $15.40   Finished port in flange does not match port in head.
    May have to dent tube to provide clearance to header bolts.
 Windsor - SVO & Aftermarket   123456789A123456789B123456789C1234567 123456789A12345678
 62-up Ford 221-351"
 SVO/AR/J302
 1 5/8", Square		 20622D $314.502 25622D $146.952 ------ ------ 28622 $29.35 29 Diagonal Center-to-Center bolt hole measurement is 2.44".
    Two Bolt Patterns - Horizontal (stock) & Diagonal across port.
 62-up Ford 221-351"
 SVO/AR/J302
 1 3/4", Square		 20622E $314.502 25622E $146.952 ------ ------ 28622 $29.35 29 Diagonal Center-to-Center bolt hole measurement is 2.44".
    Two Bolt Patterns - Horizontal (stock) & Diagonal across port.
 62-up Ford 221-351"
 SVO/AR/J302
 1 5/8", Round		 20623D $290.502 25623D $146.952 22623D $186.902 28622 $29.35 29 Diagonal Center-to-Center bolt hole measurement is 2.44".
     
 62-up Ford 221-351"
 SVO/AR/J302
 1 3/4", Round		 20623E $290.502 25623E $146.952 22623E $186.902 28622 $29.35 29 Diagonal Center-to-Center bolt hole measurement is 2.44".
     
 62-up Ford 221-351"
 SVO/AR/J302
 1 7/8", Round		 20623F $290.502 25623F $146.952 22623F $186.902 28622 $29.35 29 Diagonal Center-to-Center bolt hole measurement is 2.44".
    May have to dent tube to provide clearance to header bolts.
 62-up Ford 221-351"
 World Products, Dart II
 1 5/8", Square		 20624D $314.502 25624D $146.952 ------ ------ ------ ------   This flange bolts to the factory bolt pattern.
    Two Bolt Patterns - Both Horizontal (stock and much wider).
 62-up Ford 221-351"
 World Products, Dart II
 1 3/4", Square		 20624E $314.502 25624E $146.952 ------ ------ ------ ------   This flange bolts to the factory bolt pattern.
    Two Bolt Patterns - Both Horizontal (stock and much wider).
 62-up Ford 221-351"
 World Products, Dart II
 1 5/8", Square		 20625D $314.502 25625D $146.952 ------ ------ ------ ------   This flange bolts to the wider 3" Center-to-Center bolt pattern
     Two Bolt Patterns - Both Horizontal (stock and much wider).
 62-up Ford 221-351"
 World Products, Dart II
 1 3/4", Square		 20625E $314.502 25625E $146.952 ------ ------ ------ ------   This flange bolts to the wider 3" Center-to-Center bolt pattern
     Two Bolt Patterns - Both Horizontal (stock and much wider).
 62-up Ford 221-351"
 World Products, Dart II
 1 7/8", Square		 20625F $314.502 25625F $146.952 ------ ------ ------ ------   This flange bolts to the wider 3" Center-to-Center bolt pattern
     Two Bolt Patterns - Both Horizontal (stock and much wider).
 62-up Ford 221-351"
 SVO N351, TFS "R"
 1 5/8", Rectangular		 20626D $314.502 25626D $146.952 ------ ------ ------ ------   Also fits Trick Flow Specialties Twisted Wedge "R" head.
    Non-stock pattern - 2.75" Center-to-Center bolt hole distance.
 62-up Ford 221-351"
 SVO N351, TFS "R"
 1 3/4", Rectangular		 20626E $314.502 25626E $146.952 ------ ------ ------ ------   Also fits Trick Flow Specialties Twisted Wedge "R" head.
    Non-stock pattern - 2.75" Center-to-Center bolt hole distance.
 62-up Ford 221-351"
 SVO N351, TFS "R"
 1 7/8", Rectangular		 20626F $314.502 25626F $146.952 ------ ------ ------ ------   Also fits Trick Flow Specialties Twisted Wedge "R" head.
    Non-stock pattern - 2.75" Center-to-Center bolt hole distance.
 62-up Ford 221-351"
 SVO N351, TFS "R"
 2", Rectangular		 20626G $314.502 25626G $146.952 ------ ------ ------ ------   Also fits Trick Flow Specialties Twisted Wedge "R" head.
    Non-stock pattern - 2.75" Center-to-Center bolt hole distance.
 Cleveland   123456789A123456789B123456789C1234567 123456789A12345678
 70-up Ford 2V
 351-400"
 1 5/8", Oval		 20630D $314.502 25630D $146.952 ------ ------ 28630 $15.85    
     
 70-up Ford 2V
 351-400"
 1 3/4", Oval		 20630E $314.502 25630E $146.952 ------ ------ 28630 $15.85    
     
 70-up Ford 2V
 351-400"
 1 7/8", Oval		 20630F $314.502 25630F $146.952 ------ ------ 28630 $15.85    
     
 70-up Ford 4V
 302-351-400"
 1 5/8", Same As Port		 20631D $314.502 25631D $146.952 ------ ------ 28631 $15.85 30.5 Read Note 30.5 about port/tube sizing issues with this head.
     
 70-up Ford 4V
 302-351-400"
 1 3/4", Same As Port		 20631E $314.502 25631E $146.952 ------ ------ 28631 $15.85 30.5 Read Note 30.5 about port/tube sizing issues with this head.
     
 70-up Ford 4V
 302-351-400"
 1 7/8", Same As Port		 20631F $314.502 25631F $146.952 ------ ------ 28631 $15.85 30.5 Read Note 30.5 about port/tube sizing issues with this head.
     
 70-up Ford 4V
 302-351-400"
 2", Same As Port		 20631G $314.502 25631G $146.952 ------ ------ 28631 $15.85 30.5 Read Note 30.5 about port/tube sizing issues with this head.
     
 70-up Ford 4V
 302-351-400"
 2 1/8", Same As Port		 20631H $314.502 25631H $146.952 ------ ------ 28631 $15.85 30.5 Read Note 30.5 about port/tube sizing issues with this head.
     
 Cleveland - Exhaust Port Plates   123456789A123456789B123456789C1234567 123456789A12345678
 70-up Ford 4V 351-400"
 MPG brand Port Plate
 1 3/4", See Note 30.		 20632E $314.502 25632E $146.952 ------ ------ 28631 $15.85 30 Read Note 30.
     
 70-up Ford 4V 351-400"
 MPG brand Port Plate
 1 7/8", See Note 30.		 20632F $314.502 25632F $146.952 ------ ------ 28631 $15.85 30 Read Note 30.
     
 70-up Ford 4V 351-400"
 MPG brand Port Plate
 2", See Note 30.		 20632G $314.502 25632G $146.952 ------ ------ 28631 $15.85 30 Read Note 30.
     
 70-up Ford 4V 302-400"
 Holmstrom Port Plate
 1 5/8", See Note 30.		 20633D $314.502 25633D $146.952 ------ ------ 28631 $15.85 30 Read Note 30.
     
 70-up Ford 4V 302-400"
 Holmstrom Port Plate
 1 3/4", See Note 30.		 20633E $314.502 25633E $146.952 ------ ------ 28631 $15.85 30 Read Note 30.
     
 70-up Ford 4V 302-400"
 Holmstrom Port Plate
 1 7/8", See Note 30.		 20633F $314.502 25633F $146.952 ------ ------ 28631 $15.85 30 Read Note 30.
     
 Cleveland SVO (aluminum) - 1st & 2nd designs   123456789A123456789B123456789C1234567 123456789A12345678
 70-up Ford Cleveland
 SVO alum. 1st design
 1 7/8", Round		 20635F $290.502 25635F $146.952 22635F $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 1st design
 2", Round		 20635G $290.502 25635G $146.952 22635G $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 1st design
 2 1/8", Round		 20635H $290.502 25635H $146.952 22635H $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 1st design
 2 1/4", Round		 20635J $290.502 25635J $146.952 22635J $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 2nd design
 1 3/4", Round		 20636E $290.502 25636E $146.952 22636E $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 2nd design
 1 7/8", Round		 20636F $290.502 25636F $146.952 22636F $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 2nd design
 2", Round		 20636G $290.502 25636G $146.952 22636G $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 2nd design
 2 1/8", Round		 20636H $290.502 25636H $146.952 22636H $186.95 ------ ------ 31 Read Note 31.
     
 70-up Ford Cleveland
 SVO alum. 2nd design
 2 1/4", Round		 20636J $290.502 25636J $146.952 22636J $186.95 ------ ------ 31 Read Note 31.
     
 Big Block   123456789A123456789B123456789C1234567 123456789A12345678
 68-up Ford V8    370-
 429-460"    Passenger
 1 5/8", Oval 		20640D $314.502 25640D $146.952 ------ ------ 28640 $15.85   Smaller port "Passenger" heads.
     
 68-up Ford V8    370-
 429-460"    Passenger
 1 3/4", Oval 		20640E $314.502 25640E $146.952 ------ ------ 28640 $15.85   Smaller port "Passenger" heads.
     
 68-up Ford V8    370-
 429-460"    Passenger
 1 7/8", Oval 		20640F $314.502 25640F $146.952 ------ ------ 28640 $15.85   Smaller port "Passenger" heads.
     
 68-up Ford V8    370-
 429-460" CJ, SCJ heads
 1 3/4", Oval		 20641E $314.502 25641E $146.952 ------ ------ 28641 $20.75   Larger Port CobraJet, Super CobraJet heads.  Fits CJ SVO/AR heads.
    Also fits aftermarket heads with stock port shapes/locations.
 68-up Ford V8    370-
 429-460" CJ, SCJ heads
 1 7/8", Oval		 20641E $314.502 25641E $146.952 ------ ------ 28641 $20.75   Larger Port CobraJet, Super CobraJet heads.  Fits CJ SVO/AR heads.
Also fits aftermarket heads with stock port shapes/locations.
 68-up Ford V8    370-
 429-460" CJ, SCJ heads
 2", Oval		 20641E $314.502 25641E $146.952 ------ ------ 28641 $20.75   Larger Port CobraJet, Super CobraJet heads.  Fits CJ SVO/AR heads.
    Also fits aftermarket heads with stock port shapes/locations.
 68-up Ford V8    370-
 429-460" CJ, SCJ heads
 2 1/8", Oval		 20641E $314.502 25641E $146.952 ------ ------ 28641 $20.75   Larger Port CobraJet, Super CobraJet heads.  Fits CJ SVO/AR heads.
    Also fits aftermarket heads with stock port shapes/locations.
 68-up Ford V8    370-
 429-460" CJ' SCJ heads
 2 1/4", Oval		 20641E $314.502 25641E $146.952 ------ ------ 28641 $20.75   Larger Port CobraJet, Super CobraJet heads.  Fits CJ SVO/AR heads.
    Also fits aftermarket heads with stock port shapes/locations.
 Big Block - SVO & Aftermarket heads   123456789A123456789B123456789C1234567 123456789A12345678
 68-up Ford V8
 429-460" SVO/TFS
 2 1/8", Square		 20642H $314.502 25642H $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8
 429-460" SVO/TFS
 2 1/4", Square		 20642J $314.502 25642J $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8
 429-460" SVO/TFS
 2 3/8", Square		 20642K $314.502 25642K $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8
 429-460" SVO/TFS
 2 1/2", Square		 20642L $314.502 25642L $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8
 429-460" SVO/TFS
 2 5/8", Square		 20642M $314.502 25642M $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8   
 429-460" SVO/TFS
 2 1/8", Round		 20643H $314.502 25643H $146.952 22643H $186.902 28350H $19.95 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8   
 429-460" SVO/TFS
 2 1/4", Round		 20643J $314.502 25643J $146.952 22643J $186.902 28350H $19.95 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8   
 429-460" SVO/TFS
 2 3/8", Round		 20643K $314.502 25643K $146.952 22643K $186.902 28350H $19.95 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8   
 429-460" SVO/TFS
 2 1/2", Round		 20643L $314.502 25643L $146.952 22643L $186.902 28350H $19.95 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8   
 429-460" SVO/TFS
 2 5/8", Round		 20643M $314.502 25643M $146.952 22643M $186.902 28350H $19.95 32 Read Note 32!!!
TFS = Trick Flow Specialties brand
    Looks like Big Block Chev bolt pattern but actually wider.
 68-up Ford V8
 429-460" Blue Thunder
 2", Square		 20644G $314.502 25644G $146.952 ------ ------ 28352H $15.85 32,33 Blue Thunder brand - definitely read Note 33!
     
 68-up Ford V8
 429-460" Blue Thunder
 2 1/8", Square		 20644H $314.502 25644H $146.952 ------ ------ 28352H $15.85 32,33 Blue Thunder brand - definitely read Note 33!
     
 68-up Ford V8
 429-460" Blue Thunder
 2 1/4", Square		 20644J $314.502 25644J $146.952 ------ ------ 28352H $15.85 32,33 Blue Thunder brand - definitely read Note 33!
     
 68-up Ford V8
 429-460" Blue Thunder
 2 3/8", Square		 20644K $314.502 25644K $146.952 ------ ------ 28352H $15.85 32,33 Blue Thunder brand - definitely read Note 33!
     
 68-up Ford V8
 429-460" Blue Thunder
 2 1/2", Square		 20644L $314.502 25644L $146.952 ------ ------ 28352H $15.85 32,33 Blue Thunder brand - definitely read Note 33!
     
 68-up Ford V8 429-460"
 Extreme Machine brand
 2 1/4", Same as port		 20645J $314.502 25645J $146.952 ------ ------ 28350H $19.95 32 Read Note 32!!!
Extreme Machine
EX514 head
     
 68-up Ford V8 429-460"
 Extreme Machine brand
 2 3/8", Same as port		 20645K $314.502 25645K $146.952 ------ ------ 28350H $19.95 32 Read Note 32!!!
Extreme Machine
EX514 head
     
 68-up Ford V8 429-460"
 Extreme Machine brand
 2 1/2", Same as port		 20645L $314.502 25645L $146.952 ------ ------ 28350H $19.95 32 Read Note 32!!!
Extreme Machine
EX514 head
     
 68-up Ford V8 429-460"
 TFS brand "BBF1 A460"
 2 1/4", Same as port		 20646J $314.502 25646J $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS =Trick Flow Specialties brand
     
 68-up Ford V8 429-460"
 TFS brand "BBF1 A460"
 2 3/8", Same as port		 20646K $314.502 25646K $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS =Trick Flow Specialties brand
     
 68-up Ford V8 429-460"
 TFS brand "BBF1 A460"
 2 1/2", Same as port		 20646L $314.502 25646L $146.952 ------ ------ 28352H $15.85 32 Read Note 32!!!
TFS =Trick Flow Specialties brand
     
 68-up Ford V8 429-460"
 Edelbrock brand
 1 3/4", Same as port		 20647E $314.502 25647E $146.952 ------ ------ 28641 $20.75 32 Edelbrock brand
    Close to stock port shape/size.  Port floor is raised & slanted.
 68-up Ford V8 429-460"
 Edelbrock brand
 1 7/8", Same as port		 20647F $314.502 25647F $146.952 ------ ------ 28641 $20.75 32 Edelbrock brand
    Close to stock port shape/size.  Port floor is raised & slanted.
 68-up Ford V8 429-460"
 Edelbrock brand
 2", Same as port		 20647G $314.502 25647G $146.952 ------ ------ 28641 $20.75 32 Edelbrock brand
    Close to stock port shape/size.  Port floor is raised & slanted.
 68-up Ford V8 429-460"
 Edelbrock brand
 2 1/8", Same as port		 20647H $314.502 25647H $146.952 ------ ------ 28641 $20.75 32 Edelbrock brand
    Close to stock port shape/size.  Port floor is raised & slanted.
 429 BOSS Hemi   123456789A123456789B123456789C1234567 123456789A12345678
 BOSS Hemi Ford V8
 429" Aluminum
 2 1/8", Rectangular		 20650H $314.502 25650H $146.952 ------ ------ 28650 $29.45    
    Stock bolt pattern has 8 bolts - all in a straight line.
 BOSS Hemi Ford V8
 429" Aluminum
 2 1/4", Rectangular		 20650J $314.502 25650J $146.952 ------ ------ 28650 $29.45    
    Stock bolt pattern has 8 bolts - all in a straight line.
 BOSS Hemi Ford V8
 429" Aluminum
 2 3/8", Rectangular		 20650K $314.502 25650K $146.952 ------ ------ 28650 $29.45    
    Stock bolt pattern has 8 bolts - all in a straight line.
 Late SOHC, DOHC   123456789A123456789B123456789C1234567 123456789A12345678
 Late SOHC Ford V8
 4.6l 
 1 1/2", Round		 20680C $290.502 25680C $146.952 22680C $186.902 28680 $22.55    
     
 Late SOHC Ford V8
 4.6l 
 1 5/8", Round		 20680D $290.502 25680D $146.952 22680D $186.902 28680 $22.55    
     
 Late DOHC Ford V8
 4.6l
 1 1/2", Oval		 20681C $314.502 25681C $146.952 ------ ------ 28681 $22.55   Sides of ports slightly flattened to improve gasket sealing
     
 Late DOHC Ford V8
 4.6l
 1 5/8", Oval		 20681D $314.502 25681D $146.952 ------ ------ 28681 $22.55   Sides of ports slightly flattened to improve gasket sealing
     
 Late DOHC Ford V8
 4.6l
 1 3/4", Oval		 20681E $314.502 25681E $146.952 ------ ------ 28681 $22.55   Sides of ports slightly flattened to improve gasket sealing
     
 Late DOHC Ford V8
 4.6l
 1 7/8", Oval		 20681F $314.502 25681F $146.952 ------ ------ 28681 $22.55   Sides of ports slightly flattened to improve gasket sealing
     
 Late DOHC Ford V8
 4.6l
 2", Oval		 20681G $314.502 25681G $146.952 ------ ------ 28681 $22.55   Sides of ports slightly flattened to improve gasket sealing
     
 Late DOHC Ford V8
 4.6l
 2 1/8", Oval		 20681H $314.502 25681H $146.952 ------ ------ 28681 $22.55   Sides of ports slightly flattened to improve gasket sealing
     
 V6   123456789A123456789B123456789C1234567 123456789A12345678
 72-up Ford V6
 2600-2800cc
 1 3/8", Round		 20670B $308.002 25670B $146.952 22670B $186.90 28670 $16.65   3 Exhaust Ports in head
     Finished Header Flanges with larger ports - add $24.00.
 72-up Ford V6
 2600-2800cc
 1 1/2", Round		 20670C $308.002 25670C $146.952 22670C $186.90 28670 $16.65   3 Exhaust Ports in head
     
 82-up 3800cc Ford V6
 86-up 3000cc Ford V6
 1 1/2", Round		 20671C $308.002 25671C $146.952 22671C $186.902 ------ ------   Finished Flange Port will block port in head.  Uses 8mm header bolts.
     Finished Header Flanges with larger ports - add $24.00.
 82-up 3800cc Ford V6
 86-up 3000cc Ford V6
 1 5/8", Round		 20671D $308.002 25671D $146.952 22671D $186.902 ------ ------   Finished Flange Port will block port in head.  Uses 8mm header bolts.
     Finished Header Flanges with larger ports - add $24.00.
 82-up 3800cc Ford V6
 86-up 3000cc Ford V6
 1 3/4", Round		 20671e $308.002 25671E $146.952 22671F $186.902 ------ ------    
     Uses 8mm header bolts which are very hard to find.
 82-up 3800cc Ford V6
 86-up 3000cc Ford V6
 1 7/8", Round		 20671F $308.002 25671F $146.952 22671G $186.902 ------ ------   May have to dent tube to provide clearance for header bolts.
     Uses 8mm header bolts which are very hard to find.
 Inline 6 123456789A123456789B123456789C1234567 123456789A12345678
 52-64 Ford OHV
 215-223-262'
 1 1/2" Rectangular		 20602C $253.902 25602C $126.302 ------ ------ ------ ------    
    One piece flange has BOTH intake and Exhaust ports.
 52-64 Ford OHV
 215-223-262'
 1 5/8" Rectangular		 20602D $253.902 25602D $126.302 ------ ------ ------ ------    
    One piece flange has BOTH intake and Exhaust ports.
 52-64 Ford OHV
 215-223-262'
 1 3/4" Rectangular		 20602D $253.902 25602D $126.302 ------ ------ ------ ------    
    One piece flange has BOTH intake and Exhaust ports.
 60-up Ford OHV
 144-170-200-250'
 1 1/2" Rectangular		 20607C $253.902 25602C $126.302 ------ ------ ------ ------    
    One piece flange has BOTH intake and Exhaust ports.
 60-up Ford OHV
 144-170-200-250'
 1 5/8" Rectangular		 20607D $253.902 25602D $126.302 ------ ------ ------ ------    
    One piece flange has BOTH intake and Exhaust ports.
 60-up Ford OHV
 144-170-200-250'
 1 3/4" Rectangular		 20607D $253.902 25602D $126.302 ------ ------ ------ ------    
    One piece flange has BOTH intake and Exhaust ports.
 4 cylinder   123456789A123456789B123456789C1234567 123456789A12345678
 71-73 Ford
 1600cc
 1 3/8", Round		 20660B $177.802 25660B $87.052 22660C $92.50 28660 $15.25    
     
 71-73 Ford
 1600cc
 1 1/2", Round		 20660C $177.802 25660C $87.052 22660C $92.50 28660 $15.25    
     
 71-74 Ford
 2000cc
 1 3/8", Rectangular		 20661B $177.802 25602B $87.052 ------ ------ 28661 $15.25    
     
 71-74 Ford
 2000cc
 1 1/2", Rectangular		 20661C $177.802 25602C $87.052 ------ ------ 28661 $15.25    
     
 71-74 Ford
 2000cc
 1 5/8", Rectangular		 20661D $177.802 25602D $87.052 ------ ------ 28661 $15.25    
     
 71-74 Ford
 2000cc
 1 3/4", Rectangular		 20661E $177.802 25602E $87.052 ------ ------ 28661 $15.25    
     
 74-up Ford
 2300cc
 1 3/8", Round		 20662B $177.802 25662B $87.052 22662B $92.50 28662 $15.25    
     
 74-up Ford
 2300cc
 1 1/2", Round		 20662C $177.802 25662C $87.052 22662C $92.50 28662 $15.25    
     
 74-up Ford
 2300cc
 1 5/8", Round		 20662D $177.802 25662D $87.052 22662D $92.50 28662 $15.25    
     
 74-up Ford
 2300cc
 1 3/4", Round		 20662E $177.802 25662E $87.052 22662E $92.50 28662 $15.25    
     
123456789A12345678 Header Flange Design Comments and Explanations. 123456789A12345678

 

CUSTOM HEADER FLANGES:  While the above Header Flange Listing is quite comprehensive, because we do so much CUSTOM designing in this area, one must understand that we offer much more.  Based on already existing header flange patterns, over the years we have made header flanges:  (1)  WITHOUT PORTS for customers using the header flanges to seal the exhaust side of the motor or customers machining the exhaust ports in the flanges to match a reshaped/relocated exhaust port;  (2)  WITHOUT BOLT HOLES because the customer wanted to drill the bolt holes themselves so as to locate the ports in the flange relative to the ports in the cylinder head a certain way;  (3)  WITH SMALLER than normal exhaust ports because the flanges were going to be used as SPACERS (between a header and a head) to add clearance to a starter, oil filter, etc.;  (4)  in Finished Header Flanges, WITH PORTS LARGER than normal relative to a tube size so that a smaller tube size header could be built but with a full size exhaust port in the header flange (one that does NOT block exhaust flow out of the head); etc.  In some cases these design revisions are done at no charge but where custom drilling is performed (some movement of the bolt pattern relative to the standard location), there is a $15-25 extra charge for the time involved.  Where only ONE flange is desired out of a set of two, we charge 75% of the pair price due to the setup time involved just to make the first flange.  We do NOT make PURE custom header flanges (i.e. one of a kind designs where only one or two pieces are needed) due to the development time involved.

 

1 Port Size:　 ROUND PORTS:　 This is the Inside Diameter of the ports in the header flange measured in inches.　 ON ALL OTHER PORT SHAPES:　 This is the OD of the header tube measured in inches that, when reshaped, would fit into this port size.　 In other words, this dimension does not truly relate to the size of the port in the header flange but more relates to the tube size specified AFTER being reshaped to approximately match the port in the flange.  Keep in mind that we make many header flanges with several choices of port sizes.  We usually ship the flanges that match the cylinder head port AND the tube size being used as closely as possible.  There are reasons to NOT always ship the best match to the cylinder head port but that is usually due to customer requests or specific needs.  We always ask about this because we see no sense in blocking the exhaust port unless there is a good reason to do so.

To make header building MUCH easier, we supply the header flange with ports (those shaped other than round) sized about 1/16-1/8" oversize from a perfect match so that the tubes do NOT have to be shaped perfectly to be inserted into the port.  Port Shapes:

RD = Round,

OV = Oval,

RE = Rectangular,

SQ = Square,

DD = D-shaped port with flat on bottom in most cases,

SAP = Same Shape(s) As Port(s) in head.

NA = Not Available or Not Applicable

2 Header Flanges are priced as a set which means V8 and V6 sets have two flanges (one for each head).  Most other engines have just one flange in a set. There are several exceptions to these rules but, where applicable, they are all noted.  Unless specifically mentioned otherwise, all header flanges are 1/4" thick. If you would like thicker header flanges, add $16.00 for 5/16" or $24.00 for 3/8".  All thicker header flanges are made to order and delay header parts shipments about 3-5 days. 　　

Made to order Header Flanges and all welded items (Finished Header Flanges, Custom Collectors, parts with Welded Flanges, etc. are NOT returnable.

3 Finished Header Flanges and Header Flanges w/Starter Tubes are shipped with a complete set of header bolts.

 

 

NOTE 9: Center exhaust port is shared by two cylinders.

NOTE 9.5:  Depending on how you want to build the headers, we offer the Flathead Ford header flanges with ports all the same size or with the center port larger to allow the use of a larger tube for the increased gas flow out of the center exhaust port (which is shared by two cylinders).  Again, depending on how you want to build the headers and which header flanges you choose to use, you may want to build the center tube in a "stepped" configuration where you start at the block with a smaller tube size and then progressively step up one tube size at a time to the size you want most of the center tube to be.  Each "step" would only be 2-4" long.  Note that we have Dissimilar Tube Custom Collectors available to match to two different header tube sizes.  (Custom Collector Dissimilar Inlet tube sizes are available in these outside diameter combinations:  2 - 1 3/8" and 1 - 1 7/8", 2 - 1 1/2" and 2", 2 - 1 1/2" and 1 - 2 1/8", 2 - 1 5/8" and 1 - 2 1/4" with each inlet tube combination available with several outlet diameters.  Note that the inside cross-sectional area of the larger tube is approximately equal to the inside cross-sectional area of the TWO smaller tubes so that the gas velocity in the center tube is about equal to the gas velocities in the end tubes.  There are two versions for 1 1/2" end tubes - 2" is the more popular choice with the inside area slightly LESS than twice that of the end tubes.  The 2 1/8" tube inside area is MORE than twice as much as that of the end tubes.  Neither is a perfect match in area.) 
 
Also - we do NOT have 7/16" thread header bolts.  You will have to use standard bolts in the 7/16" thread bolt holes.
NOTE 23:  Uses 8-1.25 x 22mm Header Bolts.  Order extras as these are VERY hard to find!

NOTE 29:  J302/SVO/Alan Rood brand aluminum cylinder heads come with two bolt patterns:
     (1) the factory Windsor bolt pattern where all eight bolts are located in a straight line and
     (2) a staggered bolt pattern that has bolts arranged diagonally across each port.
Our header flanges are drilled to match the staggered bolt pattern as the factory Windsor bolt pattern does NOT have enough room between the bolts to allow a port WIDE enough to match the ports in this head.  The staggered bolt pattern, as measured diagonally center-to-center across the exhaust port, is 2.44".  NOTE 30:   These two flanges match the two different port plates made by MPG and Holmstrom.  Port plates are thin metal plates that have a "tonque" that extends into the exhaust port - blocking exhaust flow attempting to go down into the bottom part of the 351 4V exhaust port.  This blocking gives somewhat the same advantage of a raised exhaust port (and improves flow).  Port plates are sandwiched between the cylinder head and the header flange.  These header flanges allow the construction of a header whose ports match the openings in these port plates correctly - further improving exhaust flow by eliminating the gas expansion and turbulence that would normally occur when the exhaust gases enter the port of a stock 4V port size header.

NOTE 30.5:  Due to the fact that the Cleveland 4V 4 Barrel head has such a large exhaust port it creates some serious construction issues.  The port itself requires a 2 1/8" tube formed to match the shape of the port.  This is horrendously large and requires considerably tube expansion into the port when building smaller than 2 1/8" tube headers (which are usually necessary).  For most, the answer is to buy a Finished Header Flange from us where we initially form a cone out of the tube size wanted in the Finished Header Flange then, by hand, reshape the large end of the cone to match the shape of the header flange port (which matches the port in the head).  We can supply header flanges with ports that are smaller but each reduction in port size increases the amount of port blockage (once we reduce the port size to match smaller than 2 1/8" tubes).

 

NOTE 31:  The SVO Cleveland Ford cylinder head has been manufactured with three different bolt patterns.  We make header flanges for the first two designs.  The first bolt pattern, as measured center-to-center across the exhaust port, is 2.77".  Heads with this bolt pattern can be identified by the "flat" casting area across the top of the exhaust port.  The second bolt pattern, as measured diagonally center-to-center across the exhaust port, is 2.94".  Heads with the later bolt pattern can be identified by the "bump" on the top right hand side of the casting area above the exhaust port (the "bump" comes from the extra metal added so the the bolt hole could be moved upward).

 

NOTE 32:  There have been "issues" with some of these aftermarket cylinder heads as they are described as having a Big Block Chev bolt pattern (which is usually true if you ONLY check the two bolt holes on each port).   Yet, often Big Block Chev header flanges do NOT bolt on to the heads as the overall bolt pattern width on these Ford heads is actually wider.  (Then, when this happens, the ports in the header flanges don't line up with the ports in the head and, to make matters even worse, the port SHAPE and SIZE in these Ford heads can be different than that in the Chev header flange so the Chev header flange blocks the port in the Ford head reducing exhaust flow!).  This misalignment occurs because the cylinder bore center-to-center distance in a Ford block is about 1/16" MORE than that in a Big Block Chev so equally located (relative to the cylinder bore) exhaust ports with correctly located bolt patterns HAVE to be different on a Ford.  One way to check which ACTUAL bolt pattern you have is to simply take a tape measure and measure the full end-to-end center-to-center distance across either horizontal row of 4 bolt holes.  If that distance is 14.53" (14  17/32") your heads probably have the Big Block Chev bolt pattern.  If your heads have equally located exhaust port locations (relative to the cylinder bore) that distance will be 14.72" (14 23/32").  Note that the difference is 3/16" or 3 times the bore center differences between the two engines.

Two other things to consider about using a Chev header flange on these Ford heads:

(1)  These Ford heads often have raised exhaust ports so that the distance from the bottom of the header flanges to the cylinder head bolts is considerably more than the same distance on a factory Big Block Chev head.  A Big Block Chev header flange HAS to clear the top of the cylinder head bolts and is actually design compromised (thinner than ideal) by that requirement.  The header flanges we make for these heads are actually designed for these heads and are considerably more rigid (better gasket sealing) as they have much MORE metal around the ports! 
(2)  The second design improvement in these TRUE Ford header flanges is that the notches on the bottom of the header flange that provide clearance to the spark plugs are not as huge as are those on the Big Block Chev header flanges so, again, this improves header flange rigidity (better gasket sealing) as there is MORE metal in another area than that found in a Big Block Chev header flange.

 

NOTE 33:  While a Big Block Chev header flange may physically bolt to the Blue Thunder brand head, it totally blocks accessibility to the left three spark plugs (you can't get a socket on the spark plugs!) - forcing major header flange modifications.  (OR, every time you want to change spark plugs, you can unbolt your headers and then move them away from the cylinder head so that you can access your spark plugs!).  

Our TRUE "Blue Thunder head" header flange design offers THREE design advantages over a Big Block Chev header flange: 

(1)  It is correctly notched on the TOP to clear spark plug sockets (the Big Block Chev flange is notched on the BOTTOM to clear spark plug sockets);

(2)  It has correctly shaped ports so that exhaust flow out of the head is not obstructed (typical Big Block Chev flanges - even square port flanges - BLOCK all four port corners);

(3)  It is considerably more rigid (less chance of gasket failure) as there is about 25-50% more metal around the ports (even more around the bottom) than found in Big Block Chev header flanges whose bottom width is determined by the cylinder head bolts directly below the header flange (and don't forget the weakening effect of the UNNEEDED spark plug notches on the bottom!).

Another issue is that the manufacturer changed the location of the bolt pattern relative to the exhaust ports at some point in the past.  They deny this but we designed our header flange on one of their heads and sold them for several years without ever a single problem and then, all of a sudden, started to have issues.  The earlier version of these heads had the bolt pattern to the RIGHT of the newer version.  The best way of double checking which head version you have is to compare a Big Block Chev header gasket to your head.  After inserting bolts through the bolt holes in the gasket into the cylinder head bolt holes, if the ports in the gasket are centered correctly - left to right - on the ports in your head, you have what we call the "later" version.  If the ports in the gasket are NOT centered left to right, then you have the "early" version heads.  The error is close to 1/8" so it is easily noticed. 

 

 

HEADER FLANGE DESIGN DISCLAIMER: On ANY header flange made to match ANY performance/racing factory/aftermarket cylinder head, due to the fact that the manufacturer - at any time and without notice, might reshape and/or relocate exhaust ports and/or relocate spark plugs and/or change the angle of the spark plugs - we can NO LONGER guarantee port alignment nor spark plug socket clearance. If you are using ANY of these "non-production" heads (or have ported heads) and are concerned with possible port misalignment, we will select the best possible header flange to match your exhaust ports IF you send us a tracing of all ports, bolt holes, and surrounding machined edges.  (Note that FAXing is not often accurate enough for our needs.)  There is a $10.00 labor charge (no discount) for comparing tracings to current flange designs.  There is also a custom flange drilling charge of $15.00 when it becomes necessary to relocate the bolt pattern to align ports to the port tracings as accurately as possible - and NOTE that custom drilled header flanges are NOT returnable!  Otherwise, should port misalignments occur, grind flange ports where needed. If spark plug or spark plug socket interference occurs, then modify flange as needed.

J1031_pOK__pfOKip

 

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