HEADER DESIGN QUESTIONNAIRE - what WE need to know to design a BETTER header.

If you want to print this Questionnaire to take advantage of our Header Design Advice Service, go to our Print Header Questionnaire page to do so as that page prints correctly.  Note that the charges for the rendering of the Header Design Advice Service are listed at the bottom of the page.


This is the Header Questionnaire that we ask our Header Customers

or our Header Design Advice Service Customers to fill out.
Note that we ask close to 100 questions to determine

the best possible header design recommendation.

Contrast that to others who only ask

"What vehicle do you have?  What engine do you have?"


ONLY TWO questions?  Questions concerned ONLY with fit?

NO questions about what may or may not have done to the engine,

how the rest of the vehicle is setup, intended usage, where you live and/or race,

what you want the headers to accomplish, etc.?  ONLY TWO questions?  ???????


The purpose of this questionnaire is to give us an accurate description of your
vehicle, its engine and any modifications made to it, plus its intended use.

PLEASE BE REALISTIC where expectations are concerned!

Not all of these questions will concern your vehicle, but try to answer all of
those that do as the information you provide here determines how we will:
(1) Design and Construct the headers for your particular vehicle or 
(2) Recommend Specific Header Dimensions (and possibly Header Parts)
if you are taking advantage of our Header Design Advice Service.






Year, Make, and Model of Vehicle __________________________________________________  Weight __________

If vehicle is used for daily transportation, should header be designed to MAXIMIZE:

          Street Performance _______  or Drag Strip Performance _______?

If not used for daily transportation, is vehicle primarily:

          Raced with occasional street use _______ or Raced ONLY _______?

Track length:  300’ ___, 1/8 Mile ___, 1/4 Mile ___, 1/3 Mile ___, 3/8 Mile ___, 1/2 Mile ___, Other length ___________

Other use (Pulling, Mud racing, Sand dragging, Circle Track, Closed Course Racing, Experimental Aircraft, etc.).   Please describe.



Raced through mufflers? ______ Brand name, body length, inlet/outlet diameters ______________________________

Class(es) and Sanctioning Body(ies) vehicle is competing in _______________________________________________





  A.  Year, Make, Stock Horsepower Rating of Engine ____________________________________________________

  B.  Number of Cylinders ____; Cubic Inches ______; Bore ______; Stroke ______; Compression Ratio ______

  C.  Is the engine:  
          FACTORY STOCK (never been apart) _____; recently rebuilt _____; balanced _____; blueprinted _____?

  D.  Estimated Peak Engine Horsepower __________ 
                 (This value is very IMPORTANT - don’t omit it!  Also, please be realistic.)

  E.  Estimated Peak Rear Wheel Horsepower __________ 
                 (This value can be left out - above Peak Horsepower value can’t be left out.)



  A.  Carburetion (Quantity, Manufacturer, Model, CFM Rating) ______________________________________________

  B.  Intake Manifold - Manufacturer, Model, Design (180o, open plenum, tunnel ram, etc.) _______________________


  C.  Other (Injection, Supercharged, Nitrous Oxide, etc.) __________________________________________________


  D.  If using Nitrous Oxide, should the headers be optimized to work with the Nitrous On _______ or Off _______?

  E.  If using a Supercharger on the street, should the headers be designed to work with it producing
          full boost or designed to work better in more "normal" driving (little or no boost)?

          Full boost ____; Normal Driving ____



  A.  Year, Model/Version, Manufacturer, Cast Iron/ Aluminum _____________________________________________

  B.  Modifications__________________________________________________________________________________

         1.    Intake Valve Size_________________  If oversize, how much?_______________

         2.    Exhaust Valve Size_______________   If oversize, how much?_______________

  C.  Shape and Size of Exhaust Ports (give measurements in blanks)

         1.    ___________ x ____________  Round (Inside Diameter) or Oval (Height x Width)

         2.    _________________________  Square

         3.    ___________ x ____________  Rectangular (Height x Width)

         4.    _________________________  Other Shape (Send tracing of exhaust ports AND bolt holes!)

If ports have been enlarged or reshaped, send a tracing of all exhaust ports, all bolt holes, and surrounding machined edges.  Put an arrow lettered UP on the tracing so we know which way is UP as on the head!  Tracings can be done by taping a piece of paper to the head’s exhaust surface and rubbing the bolt holes, port openings, and casting edges with crayon, carbon paper, the SIDE of a pencil lead, etc.  Remember that if you are PAYING US to build your headers (or make your header flanges) - sending us a tracing allows us to double check our header flange ports against your exhaust ports to insure best port alignment!  (Note that there can be a custom drilling charge assessed IF we must relocate the bolt pattern to better align the ports in the header flange to the ports in your tracing.)

 D.  Maximum Port Flow (if known):  Intake ___________cfm @ .___________" lift,  Exhaust ___________cfm @ .___________" lift

 E.  Location of Exhaust Ports.  Are your exhaust ports AND the related exhaust bolt hole pattern

          raised from factory location?  Yes_______;  No_______.   If Yes, how much?__________________
               (There are cylinder heads that, in comparison to factory production designs, feature raised exhaust port and bolt 
                 hole locations.  These changes can affect the selection of the header flange design and MUST be noted.)

 F  (V-8 Chevrolets ONLY)  Which header flange port shape do you want?

          Round _______; Square _______; “D” shaped _______; Select whatever you feel is best _______

 G.  (Small Block Chevrolets ONLY)  Do you have Straight Plug ______; or Angle Plug ______ heads?

 H.  (290-401 AMCs ONLY)  Year of cylinder heads and/or shape of exhaust port:

          1967-1969 (Rectangular)____________; 1970-1974 (Dog-Leg or “L” shaped)____________

  I.  (352-428 FE Fords ONLY)  Number of bolt holes on exhaust side of head:  8______; 14______; 16______
                (Because there are several different heads in this engine series that have different port sizes AND different
              port locations - send tracing of ports and bolt holes so we can double check header flange port alignment.)



  A.  Factory (horsepower rating) ________ or After market (manufacturer’s name) ________________________

  B.  Cam Specs @ .050" lift or _______" lift.  Rocker Arm Ratio _______.  Factory Rocker Arm Ratio _______.

        1.  INTAKE:      Valve Lift _______________";           Duration _______________o;

                                  Opens _______________o BTDC;   Closes _______________o ABDC

        2.  EXHAUST:   Valve Lift _______________";           Duration _______________o;

                                  Opens _______________o BBDC;   Closes _______________o ATDC

        3.  Overlap _______o;  Lobe Separation _______o;  Intake Lobe Centerline _______o;  Installed at _______o.

        4.  Lifter Type:   Hydraulic ____;  Hydraulic Roller ____;  Solid ____;  Solid Roller ____;  Other _____________.

        5.  MANUFACTURER’S DESCRIPTION of Cam Grind (Street, Street/Strip, Competition, Drag, Pulling, etc.)


             Give useful or recommended RPM range) __________________________________



  A.  Flywheel Material:  Steel____; Aluminum____; Weight_______; Manufacturer_________________________________

  B.  Small Block Chevrolets ONLY - number of teeth on Flywheel/Flexplate:  ______153;  ______168.

(There are two flywheel/flexplate sizes - 153 tooth and 168 tooth - used with the Small Block Chev engine.  This causes the starter to have two different locations.  In some cases, to provide necessary clearances, we must build a header to match the starter location - therefore we need to know your flywheel/flexplate size. If you are NOT sure what size you have, count the teeth and indicate that above.  For your information, 153 tooth flywheels are found on most engines including STOCK production 64-67 Novas.  168 tooth flywheels tend to be found in earlier cars (55-57 Chevs, early Corvettes, etc.), cars equipped with 11" clutches, or with Powerglide/Turbo 400 automatic transmissions.  Flywheel size can also be determined by checking the distance between the starter and the oil pan.  If the starter is about 1" or more away from the oil pan - you have the 168 tooth size.  If the starter is only about 1/4" away from the oil pan, you have the 153 tooth size.  (Distances are relative to using original factory production starters and oil pans.)





  A.  3-Speed ____, 4-Speed ____, 5-Speed ____, 6-Speed ____. Manufacturer/Model___________________________

  B.  Automatic (model, name of company preparing transmission, converter stall speed)


  C.  Transmission Ratios:  1st ________; 2nd ________; 3rd ________; 4th ________; 5th ________; 6th ________.



       Type/Model ____________________________________________________________ Gear Ratio ___________



       Size ________, Width ________, Diameter ________, Manufacturer _________________, Tire Compound _______





  A.  Is mid-range power important to you or your type of usage? _______________

  B.  When in competition, give low/high limits of engine’s RPM range ___________________________________

  C.  Maximum RPMs used in driving/competition _______________

  D.  Shift points in RPMs:  2nd _________; 3rd _________; 4th _________; 5th _________; 6th _________.

  E.  Drag Racing:  RPMs used at starting line: ______________;  at finish line ______________

       Best Elapsed Time _____________, Best MPH _____________, Best 60 foot Time _____________

       Were these Best Times/MPHs turned with the car as described in this Questionnaire? ________________

       If not, list changes made since then ________________________________________________________________



       Expected BEST Elapsed Time and MPH (this is important) _____________________________________________





  A.  Type of Fuel (Gasoline, Alcohol, Nitrous Oxide, etc.) ___________________________________

  B.  Outside Diameter of Exhaust Pipe (between headers and muffler) _________________________

  C.  (Small Block Chevs ONLY)  List the side of the engine that needs brackets for mounting the

           alternator, generator, or coolant tank.  Driver’s Side __________  Passenger’s Side __________

  D.  (Small Block Chevs ONLY)  If your car was originally produced with a manifold mounted

           generator/alternator bracket, your headers can come with a welded mounting bracket

           (that the factory bracket bolts to) but indicate here that you

           DO WANT__________ or DO NOT WANT__________ the bracket.

  E.  (1 7/8" Small Block Chevs ONLY)  Do you want us to use the optional Adapter/Reversion Header

           Flanges (extra cost!) when building your headers?  YES__________ or  NO__________

  F.  Power Options (power steering, power brakes, air conditioning) _____________________________________________

  G.  Are you are still building this vehicle? _______________.  

           If you are attempting to be ready by a certain date, please enter that date here ______________________.

  H.  Driving/racing altitude (height above sea level) __________________ 
           (We’ll assume under 1,000 feet if left blank.)

  I.   Anything else we should know?  Any changes being planned that we should consider?





  J.  Are you using headers now?___________ If so, who made them?________________________________________

       What type of header design are they (Collectored, Zoomies, Tri-Ys, etc.)?_________________________________

       Please list the dimensions of the headers you are currently using:  Lengths must be lengths as measured 
       by you - NOT measurements taken from a listing in a catalog.

         Zoomies (no collectors):        Tube Length____________; Tube OD___________.

         4-Tube Equal Length:          Tube Length____________; Tube OD___________.

         4-Tube NOT Equal Length:  Longest Tube _________; Shortest Tube _________; Tube OD _________.

         Tri-Ys:    Primary Tubes:        Longest Tube _________; Shortest Tube _________; Tube OD _________.

                       Secondary Tubes:    Longest Tube _________; Shortest Tube _________; Tube OD _________.

         4-Tube & Tri-Ys:                    Collector Outlet (OD) ____________;  Total Collector Length___________.

       Other header information _________________________________________________________________________

  K.  If you have headers on your vehicle now, what do you want the new headers to do?




  L.  We would like to know what caused you to contact us - our website, an advertisement (magazine
       and specific issue, if possible), a new products release, a magazine article, etc.  If you happened
       to have been referred to us by another person or a business, we would like to know their name.
       If you know someone already using our headers, if you have used our headers before, or if there
       was a  PARTICULAR reason that prompted your inquiry, please let us know that too!






HEADERS BY “ED” offers a Header Design Advice Service to help people make rational, intelligent decisions regarding the purchase or construction of a set of headers.  We offer this service because we see that most people make decisions based more on LACK of information rather than on OVER-ABUNDANCE of information. (How many times have you said “If I only knew then what I know now!”?) We all learn by our mistakes but quite often these mistakes can be painful (and EXPENSIVE!).  One of our Design Advice Service goals is to help customers AVOID these “hard” learning experiences.

Because of the time that it takes to render this Service, we have to charge for the Service (costs listed at bottom). Payment may be made by either check or Credit Card (enter Card Number and Expiration Date on the bottom of this Questionnaire).  If our Design Advice gives you ONLY five more horsepower, that is actually VERY CHEAP horsepower!  If headers or header parts are ordered from us within SIX MONTHS of the Design Advice payment invoice date, the following schedule of full or partial credits will be applied to your order. Credit will ONLY be given for the SPECIFIC application described in this Questionnaire.  This credit is NOT transferable and can only be obtained by the person or business listed at the bottom of this Questionnaire.  (Please mention your Header Design Advice payment invoice number when ordering headers or header parts so that you get the amount listed below credited to your order.)



Header Purchase$59.95 - FULL Credit Given
Header Kit Purchase$40.00 - Partial Credit Given
Header Parts Order ($250.00 or more)$35.00 - Partial Credit Given
Header Parts Order ($175.00 - $249.99)$30.00 - Partial Credit Given
Header Parts Order ($100.00 - $174.99)$20.00 - Partial Credit Given
Header Parts Order ($50.00 - $99.99)$10.00 - Partial Credit Given
Header Parts Order (Under $50.00)$  0.00 - NO Credit Given


Check here if you are interested in:

HEADERS _____, HEADER PARTS _____, or ADVICE ONLY _____.  

WHAT WE WILL DO:  Design Advice Requests are answered by mail in the form of a 3-5 page letter plus 13 additional pages of interesting examples and explanations that are often referenced in the letter. Design Advice Letters are usually sent within 7-10 days of receiving the Questionnaire but this often changes during the busier times of the year so please keep that in mind and plan ahead. Priority Services:  Quicker Advice Service (1-3 day turnaround) and Quicker Mail Delivery available - see pricing information at the bottom.

WHAT YOU WILL GET:  Depending on the information you supply and which of the above three categories you select, we will recommend tube sizes and lengths and collector sizes (collector lengths should be experimented with if you’re serious about performance). If you already have headers and have described them above, we will usually include very specific design comments as to WHY we feel that our header design recommendations will further improve the performance of your vehicle.  If you are going to build your own headers, we will not only offer header design advice but will also try to give you additional specific construction and part purchase recommendations where appropriate.

COMMENT:  All advice given is based on thousands of “header design experiences” accumulated over the years.  All of our testing and experiences relate to our header designs that have always been Equal Length within +/- ½" on all  tubes and also used our Cross-+- Entry collector design.  It is this design consistency practiced over many years that allows us to make accurate header design recommendations.  If you plan on building your own headers, incorporating these two essential design characteristics plus using our tube and collector recommendations will cause your headers to achieve exactly the same power gains that we would achieve if we were building the headers for you!  If you are going to use our advice to purchase a header from another manufacturer, please keep in mind that you are NOT buying OUR headers from them - you are buying THEIR headers from them.  We see lots of headers that are nowhere near Equal Length (many even represented as being equal length), are too short (for ANY type of use), have inefficient collector shapes, and even have header flanges that block off portions of the exhaust ports in the head.  We also see lots of poor quality headers that don’t fit well, are difficult to install, have poor spark plug accessibility, leak, etc. Avoid being mislead by false claims, misrepresentations, ignorant comments, or assumptions - make sure that you get what you want!


Mail this completed Header Questionnaire to:


 HEADERS BY "ED", INC.    2710 - 16th Avenue South    Minneapolis, MN  55407


   Credit Card:               VISA _______________;  MasterCard _______________.

   Credit Card Number:  ______________________________________;  Expiration Date:  ___________;

                                        CVV2 Code (last three numbers on back of card above signature) __________.

   Amount to be charged to Credit Card:


      _______ $59.95 (U.S.A. Standard Advice Service/USPS 1st Class Mail delivery); 

      _______ $79.95 (U.S.A. Priority Advice Service/USPS Priority Mail delivery);

         _______ $61.95 (Canada & Mexico - Standard Advice Service/USPS surface delivery);
           _______ $76.95 (Canada & Mexico - Standard Advice Service/USPS Global Priority Mail delivery);
           _______ $93.95 (Canada & Mexico - Priority Advice Service/USPS Global Priority Mail delivery); 
           _______ $65.95 (Other Countries - Standard Advice Service/USPS surface delivery);
           _______ $80.95 (Other Countries - Standard Advice Service/USPS Global Priority Mail delivery);
           _______ $97.95 (Other Countries - Priority Advice Service/USPS Global Priority Mail delivery); 



   Mail Name:  __________________________________________________________________________.

   Mailing Address - line 1:  ________________________________________________________________.

   Mailing Address - line 2:  ________________________________________________________________.

   Mail City:  ___________________________________.  State:  ______.  Zip/Postal Code:  __________.

   Mail Country:  _______________________________________________.

   Day Phone:  ______________________.  E-mail:  ___________________________________________.



   Ship Name:  ___________________________________________________________________________.

   Shipping Address - line 1:  ________________________________________________________________.

   Shipping Address - line 2:  ________________________________________________________________.

   Ship City:  ____________________________________.  State:  ______.  Zip/Postal Code:  __________.

   Ship Country:  _______________________________________________.



   Billing Name:  __________________________________________________________________________.

   Billing Address - line 1:  __________________________________________________________________.

   Billing Address - line 2:  __________________________________________________________________.

   Billing City:  ___________________________________.  State:  ______.  Zip/Postal Code:  __________.

   Billing Country:  _______________________________________________.