Spitfire Mk 4 Options and Changes

Mk IV	year	changes from previous model	number made	com #	body #	engine #
	Oct 1970 (1971)	Engine: 3.89:1 final drive, heavier crankshaft and everything associated: larger big & main bearings (same bearings as 2.0 liter engines) timing cover, crank nut now 1″, heavier push rods, orange 7-bladed fan. Transversely mounted muffler, lower 3.89 final drive ratio,”sealed for life” water pump, 6V coil & ballast resistor (attached under coil bracket) now fitted, Horn relay fitted to either batttery box or bulkhead, square type Lucus 4ST starter solenoid, two-speed wiper motor (grey/silver), master cylinder mounting bracket changed slightly Interior: adjustable seats with headrests, black dash with Speedo/Tach in front of driver with black bezels, high beam switch moved to steering column, “propeller” choke knob art (early cars had “N”), wiper switch incorported pump-action washer, redesigned dash pad (center above fuel/temp guages no longer flaired out into interior & now recessed around ash tray), headlight rocker switch flush mounted without trim ring, vinyl covered dash support bracket, shift knob changed from ball to conical shape, pedals now had “L” on the rubber, interior light switch (black plastic) fitted to drivers side only, new simpler door trim, door locks changed slightly, top end of door (above lock) had slot/hole in edge to prevent stress cracks, better redesigned seats with slide handle coming out from under front of seat and long tilt handle at rear, seatbelts standard, padded sunvisors w/pass side mirror and no longer swivel to the sides, break-away rear view mirror, Body: new body style comprising of: headlight rim changed to aluminium, revised nose & rear, license plate lights, windshield unique to Spitfire & frame no longer detatchable, boot lock, 13 x 4.5″ wheels with circular holes, black wheel covers, trunk lock, 2-speed wipers, new supports under bonnet, bonnet no longer had raised edge with finishing strip, BL house badges added to bonnet near latches, plastic covers over tail lights inside boot, square door glass Suspension/Transmission:revised rear suspension”swing spring” (5 leaves not 6, mounting to differential changed), new transmission (1st gear: syncromesh and 3.5:1 from 3.75:1) based on GT6 casting (5/8″ longer), output flange increased to 3 5/8″ from 3 7/16″, differential based on GT6 except with 4 studs (6 for GT6) holding spring, 3.89:1 final drive,	70021	FH3-FH19461 FK1 (US)-?	–	FK1UE
	72	8:1 compression, 4.1 to 1 final drive, black paint around tail lights, shoulder belts with buzzer and warning light		FH25001-FH45740	–	FK25001UE
	73 (Feb)	see FH50000 changes below		FH50001-FH59689 FM1 (US)	1FH	FH1UE
	74 up to November	–		FH10001 FH 64995 (last car) FM10002 (US)	10000FH	FH10001UE

Spitfire Mk 4 changes	after commission #
	FH4169	rear view mirror stem changed from straight to curved moving mirror away from driver
	up to FH25000	Engine: 15 ACR alternator (Lucas or AC Delco) now standard, AE full-flow oil filter, crankcase breather changed, old style oil filler cap, “bump” in valve cover, AAN needles in carbs, wire style hose clamps no longer used except on radiator hoses, throttle linkage bracket attached to intake manifold, green accelerator cable, new air filter box with pipes with air pipes from front of car, timing involved a single pointer (from timing chain cover) and a hole drilled in the engine pulley,
	FH25000	sporty cam (25°-65°-25°-65°) replaced with more fuel efficient cam (18°-58°-18°-58°), Toledo engine block, coolant drain on block changed to plug, Delco Remy D204 distributor, plastic needle valves instead of brass,
	FH25501	vacuum advance tube changed from metal to black plastic
	FH28430	7.25 gallon fuel tank replaces 8.25 gallon
	FH30795	An “ECC” label was fixed to the right-hand a-post (Non-US cars only)
	FH38271	155 x 13 SR radial tires
	FH40001	US cars get smaller plastic reservoirs on brake master cylinder
	FH50000 (FM1 in US) (Feb. 1973)	1500 cc engine, Reclining seats with chrome lever, shorter seat tilting catch knob, flame retardant interior trim, course grain vinyl, wood dash, non-ferruled shift knob, chrome bezels on guages, green tint lights illuminating the Speedo/Tach, wiper knob art revised (wipe symbol top, spray bottom), TR6 steering wheel with “TRIUMPH” lettered button, improved rear suspension, night dimming brake lamp relay (was supposed to reduce the intensity of the brake lights at night or when the side lights were on to keep from blinding motorists behind), white hood was no longer available, front spoiler, fuel and vacuum lines rerouted to rear of engine thus new carbs with rear fitments, Unitac fuel pump with 5/16″ (from 1/4″) fuel line, Nylon fuel line between pump & carb bracketed to rear of head, heater core water return pipe connected to exhaust manifold stud not rear of cylinder head, larger 7.25″ (20 spline) clutch disk from 6.5″, thermostat housing no longer had large “lug” on alternator side, left side engine valance no longer attached to suspension turret, drive shafts lengthened by 1″ (along with longer hand brake cable & brake hoses), brake hoses were attached to rear cylinders via a metal pipe (previously directly connected), rear radius arms lengthened, radius arms mounting brackets changed, front roll bar diameter increased to 7/8″ from 1/16″
	FH51203	center badge on optional wire wheels changed to British Leyland logo from “Spitfire” words around the circumference
	FH53956	fuel line between pump & carb now attached to bell housing, step down connector between 5/16″ fuel line and carb, color-coded metal fuel pipe clips: green for 1/4″, dark blue for 5/16″, black for connections between fuel tank and pump
	FH5?3211	timing pointer changed to graduated timing plate
	FH60000	Front chassis changed to meet front impact regs., black rubber seal around tailights changed to cheaper sponge rubber seal, pipe between carb and fuel pump changed to metal, carb had revised float at rear, exiting the carb required a step down connector between it and t the 5/16″ fuel line, fuel line held in place at rear of head by bracket with rubber grommet, new intake manifold with t-shaped coolant exit, interior light switch in door changed to metal from plastic, optional overdrive changed to stronger J-type from D-type with switch on shift lever (previously on steering column)
	FH60977	Ugraded Lucas 16 ACR alternator, ignition wires exited the distributor at 90°
	FH62271	2 rubber bumpers (water drainage) were added to the corners of the boot lid to help prevent rust.
	FH63214	an extra support bracket added to prevent exhaust down pipe and/or exhaust gasket failure

Spitfire Mk 4 changes	after date
	February 1973	front axle stub material changed
	January 1974	tonneau covers became standard equipment (came with & without headrest cups)

*Options (dealer)	option	price (1970)
	Base Price	£735
	Hard-top kit (body color with beige headlining)	$175
	Soft-top conversion kit	?
	Bolt-on (not knock off) wire wheels (13×4.5) up to FH 60000	£47.50
	Oil cooler	?
	Tow bar attachment	?
	Continental touring kit	?
	Wooden gear knob	?
	Touch-in paints	?
	Lucas headlamp conversion mask	?
	Hood stowage cover-for use with hard-top	?
	Radio-aerial and speaker installation	?
	Skid plate	?
	Mud flaps	?

*Options (special order)	option	price (1970)
	Overdrive	£68.75
	Tonneau cover-standard from 1974	£11.41
	145-SR13 radial tires-up to FH 38271 only	£10.00
	Whitewall tires	£62.50
	Front upper ball joint with grease nipple	?
	Grease nipple for rear bearing housing and front vertical link	?
	Toughened (Zebra-Zoned) windscreen	£8.75
	Leather seats-up to FH 50000 only	?
	Head rests-after FH 60000 only	?
	Competition DS11 brake pads	?

FYI: the 200,000 the Spitfire rolled off the assembly line July 9, 1973 (US model)