Dear all,
We are currently preparing a car to get back on track after 30 years in hibernation..
It has been designed for the 1979 season of the Group 5 category, but was raced in the 1980 IMSA GTX class and the 1982-3 IMSA GTP class and to make things more complicated... altogether it did 6 races (4x IMSA GTX, 2x IMSA GTP) with 3 different engines, but was designed for an engine that never materialised..
It has an aluminum roll-cage that has been riveted to an aluminum monocoque, basically trying to get through a loophole in the 1976 Group 5 regulations which read:
" No modification may be made to the series coachwork and/or the
original chassis and bodywork, except as regards the lightening of the structure by removal of material and the adjunction of chassis reinforcements."
Comes from here
Yes.. they removed all of the original chassis for "lightening" purposes and added an aluminum monocoque as "chassis reinforcements"..only an English firm can get away with that
I've read in the App K that an aluminum roll-cage is strictly forbidden for every GT car in group 5, and for example some porsche 935 owners have replaced their alu cage by steel ones accordingly. But I've also heard rumours that this does not apply to aluminum monocoque cars, which shouldn't exist in group 5 because of the rules above and therefore it would be unnecessary to mention the exception in the appendix K for group 5..
The cage tubes are 1.5 inch in diameter and .128 inch thick, if size matters.
Replacing the cage by a steel one will be a lot of work and may damage the chassis, so we hope to get away with this original one.
So.. does anybody know about aluminum roll-cages in cars with an aluminum monocoque that are presently competing in historic racing and seem to have a "legal" status ?
Looking forward to your input,
Jan