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CALM 2022 5

CALM All Porsche Trophy

The series open to ALL Porsches of any age or persuasion

The CALM All Porsche Trophy Series is designed to offer competitors a great deal of freedom in tuning your Porsche whilst at the same time providing a framework that keeps cars competitive and cost effective. The class structure will be organised on a bhp (at flywheel) per tonne, including the driver. A mixture of sprint, 20, 40 minute and 60 minute races with a mandatory pit stop plus 20 minute qualifying session. Entries may be by single drivers or two drivers sharing the same car. Great value racing – with the ethos of safe and gentlemanly driving standards. 

2022 Calendar

18th April (Easter Monday) - Donington GP on the challenging Donington Park GP circuit layout. Qualifying and a single 40-minute race for one or two drivers

21st & 22nd May - Brands Hatch GP. A double-header of races on a shared grid of retro sports cars, with 80 minutes track time.
9th or 10th July - Thruxton. We are guests for the first time at a British Truck Racing round. A huge crowd is always expected.
31st July - Snetterton 300. Annual trip to Norfolk with 750 Motor Club. Qualifying plus a 40-minute race for one or two drivers.
10th & 11th September - Anglesey Autumn Festival. Double header with 750MC. Qualifying, two 20-min races on Saturday and single 40-min on Sunday for one or two drivers - plus a Saturday night party in the paddock.
22nd October - The 750 Motor Club’s famous Birkett Six-Hour Relay Race. In 2021 we fielded six teams in this fantastic annual event using the full Silverstone GP circuit. Teamwork and camaraderie makes the day.


SP1 - 240 bhp/tonne 
SP2 - 200 bhp/tonne 
SP3 - 180 bhp/tonne 
SP4 - 145 bhp/tonne 
SPDA - Cars previously running in the Supersport Boxster Porsche Racing Drivers Championship
INVITATION - Any car not meeting any of the above but deemed a positive entry by the organisers
Proof of power and weight must be lodged with the organisers before an entry can be accepted. The organisers reserve the right to adjust a competitor's class should lap times in qualifying dictate.



All cars must carry forward facing in cockpit cameras and must be switched on at all times when on track, even in qualifying. The SD card must be surrendered upon demand to the clerks of the meeting as evidence of any incident.


The original silhouette is, largely, to be retained from all angles, with the exception of limited production splitters, wings in the SPDA class.

Engine and Transmission

Original engine and gearbox type to be retained, internals are free, but no sequential gearboxes, unless supplied in original road car. 'Original engine and gearbox type' means the same engine (block and head) and gearbox as was available from the factory in period. 
If fuel-injected, throttle bodies are allowed, fuel-injected cars may run carburettors but not vice-versa. Fuel injection and carburettor type are free. 


Suspension & Tyres

Cars must run on either; MRF ZTR , Dunlop Direzza, Toyo R888-R treaded tyres all in Motorsport UK list 1A/1B/1C. No slick tyres allowed.
Suspension, dampers, springs arms, links and wishbones are free


Pit Stops

A mandatory pit stop is required during the 40 minute or 60 minute races. The duration of the pitstop will be adjusted according to each individual car's lap time during qualification providing the time is at least as quick as a a 'datum' time provided by the organisers before qualification. The minimum length of the pitstop will be 60 seconds.


Awards are given at each round - Class winners, 2nd, 3rd of each SP class will receive a unique trophy.