REGULATION TYRES

Unfortunately at present there is a little confusion about the correct tyres for 1000cc Formula 3 cars. It is very straightforward but some people do not fully understand so here is a simple (we hope) guide for builders, restorers, entrants and drivers. 

Note there are minor changes noted below regarding cars of period 1/1/64 to 31/12/65, details below.

If you are buying, restoring or borrowing a car to enter in 1000cc F3 you should ensure it has the correct tyres. If you have any doubts please ask the Chairman of the Series - David Pullen or Registrar - Ted Walker, via the HSCC office. If you take advice from anyone other than David, Ted or an actual, current registered competitor in 1000cc F3 you may be given the wrong information and at least one person in 2009 wasted the cost of 4 tyres through incorrect 'advice'!

There have been suggestions made by one or two people outside of the series that the only tyre that should be used are Dunlop, as these were the tyre used in period. This was the tyre used for the series prior to 1000cc F3, i.e. the Formula Juniors, (and they are the correct fitment for FJ cars now) and their use continued with the earliest 1000cc F3 cars from 1964 onwards. Fairly quickly other tyres came into use notably Goodyear and Firestone (YB11) towards the end of the 1960s.

By the late 1960s tyre compounds and construction were significantly different to that of the Dunlop tyre from the early 1960s. It was decided in the late 1980s that the Avon tyre was the best option for current day racing of these cars and has been the specified tyre for 1000cc Formula 3 ever since - about 20 years or more.    See below.

Interestingly the races in period also allowed the hand cutting of tyres with additional grooves to form ‘wet’ tyres.

A further point that may be of interest - wheel rims sizes. Almost all cars in CRC 1000cc F3 and the European Trophy run 8” wide front, 10” wide rear rims but in period they frequently ran 10” and 12” and this would be an allowable option provided the correct Avon A37/CR65 pattern tyre was used. Even more interesting aquaplaning in the rain! The eariest cars ran narrower, 6"and 8" rims typically.

The Regulations for the Classic Racing Cars series can be found on the HSCC website. Other Classes in CRC do run on Dunlop but these are NOT accepted in 1000cc Formula 3.

HISTORIC MONACO 2010

The FIA Tyre Working Group have now recommended that the following be used in the Regulations for this event:

For ‘dry’ race
Period F (1964-1965) - only the DUNLOP ‘L’ section, 204 compound, CR65 tread

Period GR (1966-1970) - Either:
DUNLOP ‘L’ or ‘M’ section 204 compound, or Posthistoric, CR65 tread
or
AVON slick cut to CR65 pattern A37 compound reference 7342 and 7343.

For ‘wet’ race
As above or AVON 7277 or 7278

Racing in Europe with F3 Historic Trophy 

For any race organised by the European Historic 1000cc F3 Trophy, the same Avon A37 tyre is specified with CR65 cut tread pattern, except for cars from 1/1/1964 to 31/12/1965 which must run  DUNLOP Vintage "L" section, 204 compound, CR65 tread pattern. 

The second difference is that for European races a 'wet' tyre is also allowed. When a race is declared 'wet' by the clark of the course, wet tyres may be used and are limited to the AVON reference:7277 and 7278 (range with diagonal carcass) according to the appendix K international sports code. The normal 'dry' tyres may still be used.

The FIA accept the Avon A37 tyre make, compound and tread pattern for these cars, as can be confirmed in their Regulations for Period G cars as below:

“3.2 Dating periods are as follows: GR) 1/1/1966 (1/1/1964 for Formula 3) to 31/12/1971 for Single-seat and two-seat Racing cars.

6.12.5 Periods G onwards (a) Wheels with rim widths narrower than period specification may be used

8.2.4 Period G (G1 and G2 - built 1.1.1966 to 31.12.1971) may use racing tyres from the Dunlop Vintage, “L” and “M” Section and Post Historic ranges, or Goodyear “Blue Streak” racing tyres, or Avon slicks hand cut to the Dunlop CR65 pattern. T, CT, GT, GTS and GTP cars may also use tyres in conformity with the rule set out in 8.4.1 below.”

HSCC/European Trophy Joint Events

As the HSCC and European series sometimes race together it has been agreed that for any Peter Hanson Trophy event (in the UK or Europe) the use of wet tyres is allowed. They are not compulsory and any car on the standard A37/CR65 tyres can race in wet conditions. Similarly, any UK car entering any of the 1000cc F3 races abroad do not have to have, or use, wet tyres if they do not wish to.

Racing in the UK

For any race organised by HSCC in the UK (excluding Peter Hanson Trophy rounds) (excluding cars 1/164 to 31/12/65) the ONLY tyres allowed are Avon A37 compound cut with a CR65 tread pattern.  The requirement is for 5 grooves in front tyres, 7 grooves in rear tyres. The photographs below show new tyres cut correctly. The sizes are front 7.5/21.00 x 13”, rear 9.2/22.00 x 13”. The supplier BMTR know the exact specification required.(This is not strictly a CR65 pattern but is the one produced by BMTR, and is the pattern that is expected)

With more very early period cars beginning to appear it has been decided to revise the CRC regulations during 2010 to bring them into line with the European Regulations, this has been agreed with the MSA. For F3 1000cc from 1/1/1964 to 31/12/1965 : the following tyre is allowed:  DUNLOP Vintage "L" section, 204 compound, CR65 tread pattern. This decision has been taken to provide more consistency between the series and taking note of the smaller wheel rim sizes that were used by these cars in period (6" and 8") which the standard Avon tyre will not fit.

Any car appearing for a HSCC race with incorrect tyres would only race with the grace of the other entrants and then would score  no points in the Classic Racing Cars Championship. Being allowed to race with any other tyre is NOT guaranteed and you would most probably lose your entry fee. Please, please contact David Pullen or Ted Walker via the HSCC office if you are at all unsure what tyres your car shouyld be on.

The current published, (and MSA approved) Regulations for the HSCC Classic Car Championship specify for Class D (1000cc Formula 3 Cars):

“5.13 TYRES. Eligible tyres are as follows: Class D - Avon A37 hand cut to CR65 tread pattern”

For access to the Avon Motorsport tyre technical information go to
http://www.avonracing.com/car_page.aspx

Front and Rear Avon A37 tyres with correct pattern