Sunbeam Imp Sport

The Imp Site

Sunbeam / Singer advert 1969

In front (twin headlights) the Singer Chamois Sport and
right behind it the Sunbeam Imp Sport.

After the tuning firms like Hartwell's had had a go at the Imp's eager engine to produce road-going quick Imps, Rootes left it quite late to produce their own sporting model. It took about two years to develop it, but finally...
October 1966 saw the birth of both the

Singer Chamois Sport

and the

Sunbeam Imp Sport
The grown-up's answer to Scalextric

Downunder, in Australia and New Zealand, the Sport was called a Hillman Imp GT.

from an advert:

Features

Gary's lilac Sunbeam Sport

Performance. Luxury. Economy. Easy to handle. Precise in control. Safe. Smart. 55bhp. Top speed up to 90mph. 36 to 43 mpg.

SportStandard
Bore 2.67"; 68mm 2.67"; 68mm
Stroke 2.37"; 60.3mm 2.37"; 60.3mm
Capacity 53.41cu.in. = 875cc 53.41cu.in. = 875cc
Max. bh power (SAE pk)  55 @ 6,100 rpm
 50@5800rpm (DIN)
 42 @ 5,000 rpm
Max. torque 7.7 @ 4,300 rpm 7.7 @ 2,800 rpm
Camshaft. Valve lift 0.310" 0.247"
Overall top gear ratio 4.138 to 1
Brakes front Servo assisted drum type
 two leading shoe
Brakes rear Servo assisted drum type
 leading and trailing shoe
Weight unladen 1,633lb. = 750 kg. 710 kg
Tyres 155 x 12 5,50 x 12
Petrol use 1 liter : 12km 1 liter : 14km
Top speed 90mph = 145kph
 30, 56, 82mph through the gears
 128kph
Cruise speed 130kph 115kph


The block, crank and transmission needed no changes. But the cylinder head was completely new. It had reprofiled ports and water passages, larger inlet valves (1.27 instead of 1.18"), double valve springs, and a high lift camshaft. Not only that, but there was carburation by twin horizontal 1.25" choke Zenith-Stromberg carburettors, a four branch tubular exhaust manifold, and an engine oil cooler mounted behind the engine, close to the rear deck. All these Sports had their engine lids slatted with 'Venetian Blind' to aid oil and water cooling.
To deal with the high temperatures, the exhaust valves were made of a very tough alloy: 28/30/4NS
The head design was slightly altered to make for better cooling around the valve seats.
Carburation was set rich over 4,000 rev. so as not to have a weak mixture at speed -- again to protect the exhaust valves.

Special accessoires: seat belts; Smiths' Radiomobile etc.

    Sunbeam Sport - Chrysler - R 66884
  Sunbeam Sport   (Chrysler UK Ltd. press photo R 66884)

Rootes News : a monthly newspaper for Rootes employees, 1966, Oct. - no.3
frontpage
Big welcome for the new models : London/ Paris debut of Hunter Vogue, Chamois and Imp Sport

REVEALED to Press and public for the first time at the Paris Motor Show, the new Hillman Hunter and the Sunbeam Imp Sport were received with an enthusiasm which augurs extremely well for the future.
The following week the new Singer Vogue and Imp Chamois models were also given a very enthusiastic reception.

From the crisp, modern styling to their performance on the road, few technical details were overlooked by critical motoring journalists. And all have given the new models their full approval.

When the Sunbeam Imp Sport made its bow, journalists were quick to assess its quality and the particular market for which it is intended.

With the approval of a critical Press added to the warmth of public interest in the new cars shown at Paris and London, there can be no doubt that there is a brilliant future in store for these models.

 

In October 1968, with the designation of the Mark 2, the trim of the Sunbeam Imp Sport was downgraded to Super Imp style. Although the instrumentation was more up to date, the ergonomics of the older car were superior.
The name Sunbeam Imp Sport was replaced in April 1970 by Sunbeam Sport. It would gain the same front styling and trim as the Stiletto in September 1970.
Its production would continue until the end of the Imp-era: March 1976.
From October 1966 until March 1976 some 10.336 Sports were produced.

In 1973 the Imp Sport came out tops in a group test (Motor 1973, June 2) against some more modern opposition of those days.

Varying Sports

The differences between the most usual Sports:

 Imp SportImp SportSport
chassis no.B492 seriesB493 series593 series
starting atB492.000.100B493.000.100593.000.000
latest in Club reg.B492.005.707B493.001.539593.139.499
made (approx.)5,6001,450no guessing
based on theMk2 shellMk3 shellChamois Sport
launched inOctober 1966October 1968October 1970
dashboardearly binnacle dashlater type round dial dashboard
seatsreclining
stitched design
non-reclining
moulded design
reclining
Sunbeam badgein black and stainless steel on the front and backon the rear panel, just above the number plate lights
side stripsstainless steel strips with black insertsred insertsred inserts
frontmatching strips on either side of a small round front panel badgefull width aluminium strip between the two headlights, with black surround, with Sunbeam on a red panelas B492, with black inserts
number plate lightin a housing above the number platetwin lights, mounted on the bumper
badge on the sidesthe doors have a shield with the words Imp SportImp Sport badges fitted to the rear wings
Early Sports had the brake servo in the luggage compartment.
The earliest Sport was B 492 000769 HSO (meaning it's the 669th off the line), registered June 1967. It was Signal Red. The earliest registered Sport was blue and had chassis number B 492 000914 HSO. It was registered on 1 November 1966.
The latest Sport was a Sunflower Yellow one, registered 28 August 1975: L 5593139499 BSA H The chassis number of the latest registered Sport isn't known, but it was an R register, and it was entered during November 1976.

"There's more than sizzle
in the Sunbeam Imp Sport
There's spice
and all things nice !"

  Hillman GT (Chrysler)
  Hillman GT - spot the badge next to the fake grill, not on it. (Chrysler brochure)

The Imp Site
   The Imp range
      Hillman Imp Sport (this page)
   The Imp Gallery
      Hillman Imp Sport / Singer Chamois Sport
      Nick's turbo-charged Sport.

This page features two Hillman Imp GTs
Check the orange one on Russell's site.
The metallic light green Sport that Mike Marsh had in SA.
he metallic turqoise Sport on Paul Waites' site.

© Franka
Version: December 25, 2013
File started: January 5, 1996

The lilac Imp (crayon drawing) used to be Gary Hardings' 1971 Sunbeam Sport as seen by an artist friend of his, who will remain nameless until Gary tells me.