1999 Pre-1973 Historic Formula Ford Regulations

The engine shall be the standard Ford 1600 pushrod crossflow, as installed in the following vehicles:

Original version: Cortina 1600 GT, through 1970 model.
Uprated version: Cortina GT 1600 (1971), Capri 1600 (1971), Pinto (1971).

Components shall not be interchanged from the original and uprated versions of the engine. Regulations pertain to both versions unless otherwise stated.

The engine shail not be altered, modified or changed in any respect, unless specifically stated herein.

Balancing of all moving parts of the engine is permitted provided that such balancing does not remove more material than is necessary to achieve such balance.

Bore may be enlarged to increase clearance between piston and cylinder. Cylinder liners may be fitted. The top surface of the block may be milled to obtain the maximum compression ratio, as specified above. Any steel centre main bearing cap is permitted.

Ports may be reshaped by the removal of metal as long as the port diameter at the manifold face of the head does not exceed the following:

Minimum volume per cylinder: 7.8cc.
Reshaping is prohibited.
A standard dimension head gasket shall be used. Head gaskets may be exchanged between the original and uprated engines. (See permitting modifications, S(ii).)

The ports may be reshaped by the removal of metal as long as the following dimensions are maintained.

The carb face of the inlet manifold may be machined to the horizontal to compensate for the fore/aft tilt of the engine.

Water passages in the inlet manifold may be plugged.

Standard .015" oversize or .030" oversize may be used in the original engine. Only standard size pistons may be used in the uprated engine.

Piston make is free provided:

(i) one oil control and two compression rings are used
(ii) no modification is made to the piston for the installation of rings.

Reshaping of the valve is specifically prohibited.

The camshaft lobe profile shall not be altered. The following specs are provided for checking only.

Valve springs and valve spring shims are free except that:

Minimum weight: both engines 640 grams
Note that weight includes cap, bolts and small end bush, but not the bearing shells.

Weber: 32DFM, 32DFD or 32/36DGV
Venturi diameter: Primary—26mm, Secondary—27 mm.

Permitted modifications:

Distributor: Standard Autolite, Lucas, or Bosch with single points only. The vacuum advance mechanism may be removed. Transistorized/electronic ignition is prohibited. Mechanically operated breaker points are to be the only means allowed to trigger the ignition.  The use of more than one set of points is not permitted.

The replacement of "metalastic" and plastic type bushings with spherical type is not prohibited.  They must, however, not result in any extra adjustability, or change the outward appearance of the original component.  Sound engineering practices must be observed.

Suspension and Running Gear - The substitution of CV joints for donuts is specifically prohibited.  All historic Formula Fords must use donuts in the drive line with the specific exception of the Merlin Mark 20A.

The driver's seat must be capable of being entered without the removal or manipulation of any part or pannel.

Wings (airfoils) are prohibited.

Monoposto Racing Historic Formula Fords will use only the following:

Note that this is approximately 5% above the original rules.  The intent is to encourage the use of all safety related items.  The use of full height rollbars, with additional fore and aft braces, dash hoops and fire-systems should not be omitted for fear of a weight penalty.

All body panels originally supplied with the model, with the exception of the engine undertray, must be used.  They must be the original shape. The car must be restored to the original period specs, unless otherwise approved in writing.