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CALM 2024_6

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. Great value racing – with the ethos of safe and gentlemanly driving standards. 

2024 Provisional Calendar

1st April (Easter Monday) - Donington National - 1x40min pitstop race
4th May - Thruxton - 1x40min pitstop race 
29th June - Brands Hatch GP - 2x25min races
3rd & 4th August - Snetterton 300 - 2x15min sprint races plus 1x40min pitstop race
21st/22nd September - Croft -  2x15min sprint races plus 1x40min pitstop race
26th October - Silverstone GP - Birkett Six-Hour Relay Race - End of season team event


The class structure will be organised on a bhp (at wheels) per tonne, including the driver. A mixture of 15 and 40 minute races (40 minute with a mandatory pit stop) plus 20 minute qualifying session. Entries may be by single drivers or two drivers sharing the same car. 

SP1 - 181-230 bhp/tonne (Blue Sticker)
SP2 - 161-180 bhp/tonne (Red Sticker)
SP3 - 131-160 bhp/tonne (Yellow Sticker)
SP4 - Up to 130 bhp/tonne (Orange Sticker)
INVITATION - Any car not meeting any of the above but deemed a positive entry by the organisers

Note power is now measured at the wheels. 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.

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 any 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 races. The duration of the pitstop may 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 class will receive a unique trophy. 


For more information, see the dedicated CALM All Porsche Trophy Website.

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