Tyre Regs -The debate! (split from Spa 6 Hours 2005)

[one-two]

Fred, I think the ideal tyre for pre-66 types is an Avon, which works on all the disciplines including the road links. There's always someone who can't get the right size, however, and for them MSA list 1A or the FIA rally list may be the way to go. Maybe you would also specify a minimum profile in addition? It's when you go beyond those lists that it gets more controversial for pre-66.

I can undertsand that the later period cars might want to use later technology and would think that's less of a problem if they are running in a separate class or competition than if they are running head-to-head with the pre-66 lot.

[Eddy V]

Originally Posted by simon drabble

so I am really confused as they seem to run Dunlop M's so why where they on yokis at Spa?

No idea what so ever Simon. I just looked it up and they (FHR) state that the "blue book" is the only way to go by. Either the drivers / teams don't give a damn when racing abroad (no German scrut on hand at Spa maybe) or they cheat like hell.

[one-two]

... or they have a 2 hour rule like FIA?

[fangio]

Any organiser, not organising a race for an FIA Championship, can allow the tyres he wants, as long as it doesn't go any further than the FIA size list.
So the FHR is allowed under current FIA rules whatever they want; just like Goodwood can restrict the tyres to Dunlops.

The 2005 DMSB regs are more restrictive it seems than the FIA rules; organisers can follow them but they don't have to. The only thaing they cannot do is allow tyres that go beyond teh FIA size list.

Eddy's suggestion is close to what I have suggested to the FIA, combined with a section rule, like 70 series until 1961, 65 series until 1966, etc.

[thatorangething]

I post this at the risk of being shot down in flames due to a big misunderstanding!!! Are you suggesting to the FIA that a pre-61 road racing saloon or road sports would have run 70 section crossplies, and a pre 66 on 65 section crossplies? Sounds about ten to fifteen years early for those respective low profile tyre sections to me, and in crossply, surely not? Those tyres would have mostly been 80 section,or 78 on a US car? I'm only guessing but it sounds like history being rewritten, unless i'm very mistaken. Are you referring to a tyre brand and type? If I am getting the wrong end of the stick then I apologise, perhaps you could clarify?

[zefarelly]

dunlop M's and L's are more like 80 and 100 profile ! I've got some photos of serious sidewall roll from M's on the back of Cortinas and alfas . . .and theyre not the heaviest cars

[fangio]

I just gave it as an example; the sizes to be used should be close to the Dunlop L sections for pre '61 and M-section for pre '66.