Sprint Championship Technical Rules Updated
19 January 2025 / Sprint Championship Panel
The recent announcement of details for the 2025 Sprint Championship raised questions and concerns from several club members. The Sprint Championship Panel has met to review the feedback, and prepared a detailed response. A few clarifications and minor changes have been made to the 2025 Technical Rules.
Why were competitors not consulted on the rule changes?
The Sprint Championship Panel is focussed on increasing competitiveness and participation. Including a large number of members in the rule revision process could have biased these decisions.
Maintaining consistency - in previous seasons, a small panel has met to review the rules based on feedback received throughout the year.
The 2025 Panel consisted of four members who compete in Standard, Super Clubman and Modified classes. They are highly experienced with the rules and have received feedback from other competitors throughout 2024.
Trying to get consensus from a very large group of people on a set of rules is very challenging and not everyone will be happy.
Why are we continuing with our own Class system instead of just adopting CSCA rules?
The CSCA rules are deemed to be unsuitable for our Club competition. They are limited for our MX-5 competitors because all variants of naturally aspirated MX-5s fall within the one 0-2000cc capacity category. Hence, 1.5L NDs and 1.6L NAs would be competing directly against 2L NCs and NDs. While we accept that these rules are designed to suit the CSCA Championship which covers the full breadth of vehicle capacities, this is not a fair competition at our Club level. The CSCA rules also do not have a Standard class which attracts large numbers of MX-5 competitors and provides an entry point into motorsport. Hence, Standard MX-5s compete against lightly modified MX-5s in the CSCA Class M, which is not fair for our club competition. Our members will be eligible for both competitions and are free to set up their car to suit the competition they want to focus on.
Why is the Regularity Class not included in the 2025 competition?
The Regularity Class was introduced for the 2024 season with the aim of attracting participants who rarely entered club track days, and arrest the decline in total number of participants. A total of 13 members competed in 2024 Regularity Class, with 1 doing all three rounds, 3 did two rounds, and the other 9 only one round. At most there was only 7 competitors in a round, which required a dedicated run group. Only a few of these competitors did not enter club track days in the previous season. The trial did not significantly achieve the desired aim because the total number of competitors in 2024 (83) was identical to the total for 2023. Meanwhile, operating the Regularity Class at club track days increased complexity in operation of timing and the processing of competition results for the point score.
Having a regularity class in 2025 would require the CSCA member clubs to support a regularity competition and organise their grids accordingly, as it would not be fair to mix sprint and regularity drivers in the same run group. As this is our first season with CSCA, it was deemed inappropriate to make such a request. It may be possible to have Regularity Class added in future.
Why are R-spec tyres now permitted in all classes?
It was recognised that in recent years, the use of “Super 200” tyres such as Yokohama A052, Bridgestone RE71RS, etc achieved lap times similar to historical records with R-spec tyres. Evidence of this is available in the 2025 Class Benchmarks document. This gradually complicated and compromised the calculation of benchmarks over the last few years. It was also recognised that some R-spec tyres are available for significantly lower cost than Super 200 tyres, such that continuing to permit Super 200 tyres but not R-specs is counter to the aim of minimising costs for competitors. It is likely that tyre technology will continually evolve. Opening up the choice of tyres for all simplifies the rules and their management, while increasing the options for everyone. Finally, R-spec tyres are permitted in all CSCA classes, which improves the competitiveness of our drivers in that competition.
What is the reason for wheel size restrictions in Standard and Clubman?
In Standard, the wheel size must be as specified by the manufacturer. The exception is NAs and NB8B/C/Ds are permitted 15” wheels with the original width. The reason for this exception is to increase availability of suitable track tyres.
In Clubman, wheel diameter may be ±1”, while wheel and tyre width may be +1”. This limitation has been in place since Clubman was introduced many years ago. It is designed to be consistent with road registered vehicle requirements.
As all naturally aspirated NBs and NA8s are in Category B, it has been decided that the maximum tyre width permitted for all these models in Clubman is 230mm, wheel width is 7.5” and wheel diameter is 17”. The 2025 Technical Rules have been updated to reflect this clarification.
Why are body modifications not permitted in Clubman?
This takes away from the spirit of the Clubman class, as body modifications to improve aerodynamics are not in line with “common modifications” to be made to a car. The spirit of Clubman class is to have cars that look relatively standard with OEM body kits permitted. Body cutouts significantly change the appearance of the car which is not consistent with the spirit of the rules.
Why is any ECU/ECU software upgrade permitted on naturally aspirated cars in Clubman?
This change was made because Clubman and Super Clubman classes were merged, so modifications that were previously available to Super Clubman, are now also available to Clubman. The intention was to avoid pushing Super Clubman cars into Modified. In recognition of concerns about the potential costs involved with customised tuning of ECU software, this modification has now been changed from 1-point to 2-points. This change reflects the options available with exhaust modifications, e.g. non-standard exhaust header/downpipe and mid-pipe and/or muffler count as 2-points total.
In reconsidering the question of ECUs to customise ignition timing, it was recognised that advancing timing on NAs by adjusting cam angle sensor position within OEM range is a practice that has been commonly used for many years in Standard class. It is not considered to be a modification as it is a simple mechanical adjustment on par with a wheel alignment within the OEM range. However, the installation of an ECU software upgrade is considered to be a modification.
Is the NSW Supersprint at One Raceway included in the Sprint Championship?
No! Sorry, there was a misunderstanding and it was mistakenly included in the previous News story (which has been corrected). The NSW Supersprint round on 18 May will NOT count towards the Sprint Championship. The Sprint Championship will consist of five rounds. This decision was made because it creates significant management complications for the Supersprint round.
