Group 3 & 4 Homologation Info

Hi All

This a follow on from the Beta Coupe enquiry, but I guess covers the Stratos as both homologated at the same time from what I have read.

So, if anyone can enlighten me on this I would appreciate it.

My understanding so far…..

Group 3 was a classification for standard road cars with very restrictive (no?) mods allowed to standard production other than safety etc. Min production was I guess 500 given the amount of Stratos's produced.

Group 4 was for modified cars which qualified for Group 3 with only mods being the parts listed in the additional homologation papers to the original Groups 3 ones. No limit on production quantities etc I assume?

I know that is a quick summation of the rules in 1974/75, my main query is WHAT mods were allowed to Group 3 cars as obviously you could not enter a rally with a fresh off the production line car? Also with the Beta engine, there is a well documented issue with oil pump starvation which will screw the bearings under hard cornering, would sump mods be allowed etc in Group 3?

Sorry if this has been covered many times before, but a quick search did not find much on the subject.

Peter

The Group 3 racing class referred to a setof regulations for Grand Touring Cars competing in sportscarracing and rallying events regulated by the FIA. These regulationswere active, in various forms, from 1957 to 1981
1966to 1969
The FIA introduced a new Group 3 Grand Touring Car category in 1966 aspart of a major revision of the Appendix J regulations.^[7]The production minimum required for Group 3 homologation was raised to 500units and models such as the Ferrari 250GTO and Porsche 904 were reclassified to the new Group 4 Sports Car category with its lower 50unit minimum.^[7]The International Championship for GT Manufacturers was discontinued for 1966and replaced by the International Championship for SportsCars.^[6]GT cars were eligible to compete with the Group 4 cars in rounds of the International Championship for SportsCars in 1966 and 1967 and then in the new International Championship for Makeswith Group 4 Sports Cars and Group 6 Prototype-Sports Cars in 1968 and1969. An International Cup for GT Cars wascontested concurrently with the Makes Championship from 1968.^[8]
1970to 1981
The creation of a new Group 4 Special Grand Touring Carcategory in 1970 saw Group 3 renamed as Series Production Grand Touring Carsand the minimum production requirement increased to 1000 units.^[9]Group 4, which allowed a greater degree of modification to the competingvehicles, had its minimum production requirement set at 500 units.^[9]Both GT categories were eligible to compete in the International Championship for Makesand then, from 1972, in the renamed World Championship of Makes. TheInternational Cup for GT Cars also continued. In 1976 the World Championship ofMakes was restricted to production derived cars (FIA Groups 1 to 5) and theInternational Cup for GT Cars was discontinued in that year.^[10]
The Group 3 Series Production Grand Touring Car category remained validthrough to 1981 ^[11]with the FIA introducing a new Group B Grand Touring car category the following year.^[12]
Rallying
In rallying, there were classes for Group 1, Group 2, Group 3 and Group4 cars. The Lancia Beta Coupe, was homologated into bothGroup 3 and Group 4, with the Group 3 car running the mass-produced 8-valveengine, and the Group 4 version running the more powerful 16-valve.

Hi Griff

Thanks for that, out of interest where did you find the ref?

So the above says that G4 was not related to G3 which is not what I had previously been told, i.e. you could solely qualify a car for G4 without first qualifying it for G3, which makes sense given the prod numbers of G3.

Still leaves the 'what mods you can do with G3' to be answered, anyone?

Peter