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

[one-two]

Peter, please see 8.3.8 which - as I understand it - is the one that matters for endurance racing unless the race organisers say something different (as many do). There was alot of fuss at Spa last year when cars in the 6 hour race proper ran Yokies under this reg.

[simon drabble]

I now see where you are coming from - the problem was that a few cars took the rules by the letter of teh law and in one particular case qualified with a very quick time but I think I am right in saying that they were asked to not race with them - I could be wrong as they didnt finish it is again academic. However the 6 Hour this year specified no yokis. I think it is unlikely that they will allow yoki's again.

[Peter Mallett]

Originally Posted by one-two

Peter, please see 8.3.8 which - as I understand it - is the one that matters for endurance racing unless the race organisers say something different (as many do). There was alot of fuss at Spa last year when cars in the 6 hour race proper ran Yokies under this reg.

I see your point but the important thing is the aspect ratio or the profile "running in period". As far as can see you still need to run an "L" or "M" section tyre even if it isn't Dunlop. Hence Yoko's or Dunlop D98's are not allowed.

[one-two]

Sure, I haven't measured it myself, but some clearly think the Yokies can meet the diameter requirement for pre-66 cars. There's little doubt that they do so for the pre-71 cars.

[Peter Mallett]

Hmm,

Interesting point. Of course its not a problem for me because I run on a post 1977 Championship/series.

[thatorangething]

So how many people share my belief that any alternative tyre that may be allowed, under adverse conditions,in a long race,whatever, even a road tyre, should reflect the aspect ratio of the type of tyres the car ran in period. Put yokis on your 66 mustang w.h.y. if you like, but in 80 or 85 section,if you can find them...! That then limits mechanical grip therefore the dragster and cornering ability of any car, and takes the excessive loads away from suspension and steering systems that were designed to run with little grip or side loading. As a result the cars then ALL have to drive in period, the best drivers come to the front, we get to see ALL the cars four wheel drifting like they are supposed to. Isn't that the basic spirit of the FIA regs, but with unplugged loopholes?

[Peter Mallett]

I agree with that. Tyres to suit the period of the car are fine and the regs clearly require this. The problem is interpretation.

[simon drabble]

Originally Posted by one-two

Sure, I haven't measured it myself, but some clearly think the Yokies can meet the diameter requirement for pre-66 cars. There's little doubt that they do so for the pre-71 cars.

I dont think any race organiser has agreed with them though and therefore as I said previously its pretty academic!

[PeterMorley]

Originally Posted by thatorangething

So how many people share my belief that any alternative tyre that may be allowed, under adverse conditions,in a long race,whatever, even a road tyre, should reflect the aspect ratio of the type of tyres the car ran in period. Put yokis on your 66 mustang w.h.y. if you like, but in 80 or 85 section,if you can find them...! That then limits mechanical grip therefore the dragster and cornering ability of any car, and takes the excessive loads away from suspension and steering systems that were designed to run with little grip or side loading. As a result the cars then ALL have to drive in period, the best drivers come to the front, we get to see ALL the cars four wheel drifting like they are supposed to. Isn't that the basic spirit of the FIA regs, but with unplugged loopholes?

There should be no question that tyres used in historic racing should be the same dimensions (diameter, width & aspect ratio) as original - anything else is Modsports.

But that might not be enough in iself - some time ago Kleber made a very sticky 'road' tyre that was the same dimension as some original tyre (fitted to Spridget type cars). So it was perfectly legal and (apart from the tread pattern) looked to be the right size - but the amount of grip it offered was totally in-appropriate (like the Yokohamas I just bought for a Mini based road car project!).

There is also the problem of knowing what size the original tyre really was - the current Dunlop racing tyres are wider than the originals that bear the same markings. It seems you can't always believe the markings.

Even in series where they insist on 'original type' Dunlop racing tyres there is a tendency to use a more modern tyre than is appropriate - cars that originally ran R5s use L-sections etc.

I don't think there is a problem with the FIA side, it is more a question of what the organisers have decided - the simplest solution would be for the competitors to bring pressure upon the organisers to exclude in-appropriate tyres.

[one-two]

There is a problem with the FIA regs to the extent that they don't limit tyre choice in the way that many competitors seem to think they should, but I agree that the solution is for organisers to be clear about tyres in their own supplementary regs. To be fair, the better series are already run that way.

[one-two]

For those that are interested, I see that there is a brief piece on this issue in the latest copy of Historic Motor Racind News. John Quenby reports that the view that the present regulations are too liberal didn't prevail at the FIA's Historic Motor Sport Commission meeting last month and the powers that be decided they were just fine.

[thatorangething]

Well if thats what the powers that be think, then fine. I'm with Peter Morley in that to run anything other than original diameter and aspect ratio makes the car a modsport/saloon, and i'm old enough to remember what they were! Doesn't the FIA classification mechanism exist to protect each given time period in history in order to maintain the spirit and appeal that the racing had in period?
In a way what they are failing to do is to get a grip on are the number of modsports and saloons creeping in to FIA racing, and are allowing owners to subtly modsport their "FIA" racer and still run it as an "in-period" original, there were a few obvious examples running at spa, under different guises. I love the idea of seeing the return of the various modified groups, but in their own classes. As to the issue of the difficulty of identifying what wheel/tyre/aspect ratio/diameter set-up a particular car ran in period, surely the papers for that car would identify the spec, otherwise the car would be a prototype or modsport? Maybe it's time for Jim Tiller's Allard to upset a few people!!

[zefarelly]

I'm happy with the tyres we run, I don't have a problem with other people running different tyres if they want to, but you can't race safely with half the cars on low profile modern slicks and the other half on period high profile crossplies

[fangio]

This is what I put on the Spa 6 hrs debate, not having seen this has been split off:

The Yokohama's are allowed by the FIA in any FIA event, even their own Championships.
The only rule that exists now, is a diameter size rule, giving minimum wheel diameters for each period and each wheel size (13-14-15 inch etc), and there is a 2 hr rule.
As long as the tyre diameter fits in that list, it is allowed, which simply means that we are going to see possible even more modern, very efficient "road" tyres on Historic racing cars.
We should not focus on the Yoko's, it's not their fault that they make very good tyres....., but the fact that within the rules modern tyres are allowed that in some cases are based on slick type construction.

It is up to the drivers and the Historic Commitee to decide what we want in Historic Racing; do we want these tyres or not?
I think they don't go with the strict rules that try to keep cars to their original specs and on some cars they are potentially dangerous because of the high loads put on suspensions.

additional: But I believe the Technical Working Group is looking at this and may come up with slight modifications.
A problem remains with mixed road/race event like the Tour Auto, where basically you must use the same tyre all along, both for the road (approved tyres) and the racing part; so there any modern sticky tyre is allowed even if it's a short race.

I believe that Dunlop racings and tyres like the Avon's will do perfectly (I am talking pre- 66).

[john ruston]

Thanks-the Dutch have it precisely correct,the Carol Spagg regs are for the series The FIA regs need to be rethought and it not only Yokos,Hoosiers on the GT40's etc Best of luck boys I am going to play golf whilst thev rules and the screut are sorted its cheaper and less breaking of the rules

[zefarelly]

Originally Posted by john ruston

I am going to play golf whilst thev rules and the screut are sorted its cheaper and less breaking of the rules

theres the problem. the people who want clarified rules to make it safer and a level playing field will go and play elsewhere if at all. So it basically down to the organisers to take a stand and take the risk of being successful.

I've met just as many cheating golfers as I have racers, and I don't play golf per se

[one-two]

So, now we agree on the problem, we need to lobby the FIA to change its regs and lobby individual race organisers to apply the right supplementary regs. It sounds as if the six hours is a good place to start on the latter (though, at the risk of adding complications, there still be problems with races that run across the pre- and post-66 periods.)

[simon drabble]

so one two do you favour yokis in the races or dunlop/avons (depending if its declared wet race)?

[one-two]

I think historic cars should race on historic tyres. I think it's easiest if that is defined as Dunlop Ls or Ms or earlier, and I think that is the way the best-run and supported series are already organised. I think Yokies are a great tyre and are suitable for post-66 (or post-71), but not pre-66. The only issue I would see arising in future would be if pre- and post-66 cars were to appear on the same grid to different tyre regs.

[simon drabble]

so we are all in agreement!!! I do also agree with you about running two grids at once as well - I am sure the 6 Hour would still be as profitable if they did as more pre 66 would come out to play.
As a matter of interest you seem well informed - are you racing as well and if so what?

[fangio]

John, I know they have faster flying golf balls, so make sure you have the old Dunlop balls......
one-two, be careful to talk just about Yoko's, as there are other tyres (especially in the US) that could be just as modern and quick.

[Fred Gallagher]

Before we get too involved in balls can I have some opinions about what the tyre regulations should be for the various Tours (Auto, Espana, Britannia...)?

Fred

[thatorangething]

I think it is more appropriate to apply a straightforward rule to any period historic racing class, in that the car must race with the correct rim width diameter, as now, but correct tyre tread width, profile and aspect ratio,and correct overall tyre diameter. It should be that simple.

Any car that runs a modern or relatively modern tyre with a reduced overall diameter is simply not a period racer, whatever the excuses are.

Show me for instance a 67 Mustang that raced as a road/race car in period with list 1B radial tyres in 60 or 70 profile, then i'd say let it race. If no such combination existed in 1967, then stop it being used now.

If a crossply was the only thing available for a given type in period, then the car will not drive 'in period' on radials, and so on. There is no need to fudge this issue.

[Eddy V]

DMSB (German NMSA) tyre regs for historic racing (ie FHR), App. K:
- period C from 01-01-1919 to 31-12-1960: Dunlop Vintage (204/R5)
- period F from 01-01-1961 to 31-12-1965: Dunlop Vintage L or M (204/CR65)
- period G from 01-01-1966 to 31-12-1971: Dunlop Vintage L or M, Goodyear Blue Streak, Avon slicks with handmade profile.
- period H from 31-12-1971 onwards: slicks or raintyres (free)

These were the 2005 regs, as soon as the new "blue book" arrives, I'll put the changes in. FHR refer to the DMSB blue book for tyre regs.

[simon drabble]

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