Jody Scheckter's Merlyn Mk21 in the pits at
Brands Hatch.
 
Colchester Racing Developments were the company behind Merlyn cars and their first design was the Mk1, a front-engined Formula Junior car designed by Selwyn Hayward in 1960 that was never actually raced. More Formula Junior cars followed, switching to rear-engined designs with the 1961 Mk3. The first F3 design was the Mk7 of 1964 which was also suitable for F2 (depending on the engine fitted), Chris Irwin showed it was a potential front runner in F3 whilst David Hobbs also had some good runs in the F2 version. Several F2 and F3 designs followed and although occasional successful Merlyn never achieved that final surge that would have moved them up with the big boys. Ultimately it was in Formula Ford that they made their biggest mark with a succession of highly competitive cars during the late 60's/early 70s, models such as the 11, 11A, 17 etc. would bring numerous race wins and championships to Merlyn. Financial problems and a switch to precision engineering meant that Merlyn stopped producing racing cars in 1979.
 
  
Chris Irwin in the Mk7 at Oulton Park.

Merlyn's first F3 car the Mk 7 was a dual purpose design also intended for F2, it consisted of a spaceframe chassis that extended behind the rear driveshafts had some aluminium sheet stiffening around the cockpit to increase the torsional rigidity but limited the fuel capacity. Suspension was conventional with the front inboard and the brakes outboard. It showed some promise with Chris Irwin running well in several races with his Holbay engined car taking a win at Aintree and challenging Jackie Stewart on several occasions. Eleven Mk7s were built in both F2 and F3 guise.

 
  
Les Roberts in the S.M.A.R.T. Mk9 at Brands Hatch.

1965's offering, the Mk9, was a rework of the Mk7, the sheet stiffening was removed to help with the fuel capacity and general accessability. The rear opf the chassis now finished in front of the driveshafts whilst the front suspension remained inboard. Results were mixed with Chris Irwin taking very good seconds at Monaco and Clermont Ferrand and John Fenning winning at Montlhéry, but there were few good finishes in the UK. Several cars appeared in Germany and several top six places were taken.

 
  
Another rework for 1966 with the Mk9A, the most obvious change being a switch to outboard front suspension, several MK9s were converted to 9A spec. Merlyn priced their cars at a lower cost than most of their competitors so they sold several, unfortunately not to anyone especially quick. Almost no decent results were recorded with no finishes in the top four at any of the more important races. In total 14 Mk 9 and Mk 9As were constructed in both F2 and F3 versions.
 
  
Tony Lanfranchi's Mk10 at Brands Hatch.
Basically a productionised Mk9A, the low price of £950 (£500 cheaper than a Brabham, a lot of money in 1967) still attracting several customers who all felt the car was an improvement. Merlyn's proudest moment must have been in June when they finished 1-2-3-4 at Opatija in Yugoslavia against, it must be admitted, not very strong opposition. Nevertheless there were several top six finishes from Dave Walker and Tony Lanfranchi took a win at Brands Hatch as well as seconds at Brands Hatch and Silverstone, a third at Enna, all of which indicates there wasn't a great deal wrong with the Mk10.
 
 
  
Lanfranchi again in the Mk14A.
The Mk14 was based on the 1968 F2 model the Mk12 which in turn came from the Mk10. Only one Mk14 was built and it was raced from the Monaco GP support on by Tony Lanfranchi, later in the year the production version, the MK14A, was introduced. There weren't many takers and results were disappointing although Lanfranchi took an early season second at Oulton Park and sixth at the Monaco GP support race. Towards the end of the year Lanfranchi had some promising runs that weren't reflected in the results.
 
  
Harry Stiller in the Mk14AX at Brands Hatch.
Merlyn continued with the Mk14A for 1969 but their season was largely ruined by a road accident to Lanfranchi that kept him out of racing. Later in the season Harry Stiller appeared in the Mk14AX, it had a new body and had some features that were being "tested" for the Mk18 a rumoured monocoque design with a tubular engine frame that never appeared. There were no top six results in any important races.
 
  
Jody Scheckter in his Lucky Strike
sponsored Mk21.
Jody Scheckter began the 1971 season driving the EMC but then switched to the works Merlyn Mk21, he soon had it running at the front with his somewhat hairy but quick style. He won at Oulton Park, Thruxton and Mallory Park showing that this was a very promising design, if only he had driven it all season he might have been able to challenge Dave Walker in the Lotus 69.
The Mk 21 was a space frame design with a conventional double wishbone suspension and inboard rear brakes. Most obvious feature were the prominent bulges on the flanks housing the fuel tanks. A Holbay engine was the chosen power plant.
 
  
The bewinged Mk21 in 1972.
There seems to be some argument about the 1972 car, some sources call it the Mk22 but it usually appears in the results as a Mk21 and according to the Merlyn Cars official web site the Mk22  was a "midget" car built for oval racing in the USA. It would seem that the MK21 was tidied up  with slight bodywork changes for 1972 but whatever the chassis designation surprisingly it was  no longer competitive, the best result being a 6th place for driver Hakan Dahlqvist (also spelt as Dalquist) at Magny  Cours.
 
  
Dahlqvist continued to race his chassis in 1973, it was now nearly always listed as an Mk22, (but see the 1972 entry above), it was occasionally still competitive. Part way through the season ex-works Lotus F3 driver Bernard Vermilio appeared with a newly built Mk21 which again throws doubt on whether the Mk22 was ever a correct designation although on occasions Vermilio's car was also listed as a 21B and a 22.
 
  
The Mk27 was announced as the new Merlyn F3 challenger for 1975, but it would seem it was never actually constructed. One or more chassis with the Mk23 designation appeared in German F3, one again driven by Hakan Dahlqvist of Mk22 fame, according to the Merlyn web site this chassis number was not used.
 
Drivers  
   
1964

Mk7
Roger Brash, Chris Irwin, Alain Leguellec, Tico Martini, Vincent Palmaro, Johnny Rives, Claude Robert.

Mk5
David Baker, Bill Bradley, Howard Bennett.

Mk3
Max Harrieder.

   
1965

Mk9
Ken Bass, Roger Brash, Tim Cash, John Fenning, Jean-Marie Guyot, Chris Irwin, Vincent Palmaro, Richard Peel, Leslie Roberts.

Mk3
Lionel Charlwood.

?
Jean Chicard, Georges Crenier, Dupin, Hughes de Fierlandt, "Fred", Moisset, Gilbert Salles, Börje Sköld, Daniel Vanderborght

   
1966

Mk9
John Andrews, Tim Cash, Chris Craft, Georges Crenier, Dieter Frentzen, Mike Knight, Jeff Roberts.

?
Jean-Marie Guyot, Sten-Olof Pettersson, Börje Sköld, Jürgen Wolz.

   
1967

Mk10
Ian Ashley, Michael Bartle, Ken Bass, Tim Cash, Barry Collerson, Georges Crenier, John Fenning, Roger Keele, Kurt Keller, Tony Lanfranchi, Per-Jonas Qvarnstrom, Martin Stephani, David Walker.

Mk9
Paddy Allfrey, John Andrews, Tim Cash, Gunnar Elmgren, Alan Stubbs.

Mk7
Edward Jacobsson, Roy Johnson.

?
Björn Engström, Börje Sköld, Andre Willem.

   
1968

Mk14A
Tony Lanfranchi.

Mk14
Tony Lanfranchi.

Mk10
Mats Byström, Georges Crenier, Leif Hallgren, Tony Lanfranchi, Lars Lindberg, André Willem.

Mk7
Franz Graf
.

?
Andre Willem.

   
1969

Mk14AX
Harry Stiller.

Mk14A
Patrick Champin, Tony Lanfranchi.

Mk14
Quentin Fraser, Eduard Wahl.

Mk10
Leif Hallgren.

   
1970 ?
Peter Korda.
   
1971

Mk10
Günter Kölmel.

Mk21
Jean Pierre Casegrain, Jody Scheckter.

   
1972   Mk21
Hakan Dahlqvist, Peter Lamplough.
   
1973

Mk21
Conny Ljungfeldt, Bernard Vermilio.

Mk22(?)
Hakan Dahlqvist..

   
1974 Mk23(?)
Hakan Dahlqvist.
   
1975 Mk23(?)
Hakan Dahlqvist
, Lars Olsson.