SlotForum banner
1 - 10 of 10 Posts

· Registered
138 Posts
Discussion Starter · #1 ·
Hi all,
Until recently I have been dabbling in retro cars, but my interest is growing, I have even participated in one meeting (Bordeaux) & booked entries in a couple of others. Good support is available at my local club, Oaklands Park, from Ralph Parker & Eddie Grice.
Currently my interest is drifting towards 1930s & up to 1960 F1 cars, but the decision is whether to go for true scale & perhaps have good looking cars, that are not as competitive, or stick to the CSCRA car standards. To illustrate my point, one car I am considering is the Vanwall.
If I build to CSCRA standards & go for best roadholding, the car will have 19mm min dia front wheels + tyres & 21.5mm min dia rears, with 2mm ground clearance. If I go for close to scale, I will have nearer to 24mm dia front wheels + tyres & 26mm dia rears & substantially larger ground clearance. Using an offset crown gear will allow me to take a millimeter off the ground clearance. I cannot imagine the close to scale car will be as good on the track as the CSCRA approach car?
I am basing the closer to scale wheel tyre sizes 24mm & 26mm dia, on the wheels & tyres various retailers recommend for a Vanwall, maybe they are mistaken!? If this is the case, my apologies for having got it all wrong!!!
I am verging on disappointed that the 2 approaches, CSCRA & 'close to scale', are not nearly identical & should ask, why not?
I think the wish to be as competitive as my driving will allow, points me in the direction of adopting the CSCRA standards, but maybe the experts 'could shine a light' on a beginers confusion?
After reading some of the exchanges on Slot Forum, I will now go and don my body armour!


· Registered
4,084 Posts
Fools rush in where Angels...
Hi Stan.
We have meet at Oaklands.
As a new(ish) member of this forum, you may have missed some of the very interesting and keenly debated threads on the issue of Scale. Suffice it to say, many opinions are exchanged and no common consensus is ever reached!
As for the CSCRA dimension rules, they are a practical set of age related rules which try to get a reasonable scale min/max rule for the era they cover.
The Vanwall, is a CSCRA class 3 GP model. This covers all GP models from 1952- 1960. Within that time frame there would have been models that would have used both scale 21.5mm rear and 19mm front, in fact there may have been some that used smaller!
I would suggest you do some research into the real size of both front and rear wheel/tyre sizes for the Vanwall, as you may find thet are slightly smaller than the size you have quoted.
Even if it turns out those figures are correct, you can certainly build the chassis with 2 mm ground clearance, and the 7.5mm max width rear tyre is in no way over the top for a good 'scale' appearance.
If any set of racing rules just said 'exact scale of the prototype' for wheels and tyres as well as all other dimensions even with a 'sensible' +/- of 1/16 (1.5mm) you would have very few different models entered.
Build it with wheels and tyres that comply to the rules, but look 'right'.
Kind Regards Bill.

· John Roche
4,390 Posts
Hi Stan,

Rules are always a compromise between exact scale and raceability . It gets even worse when we get to the 60's as the pace of race car development rocketed and tyres grew fatter by the year.

For example if you are racing 1.5 litre F1 cars models from '61 would have tyres around 7.5mm wide and by '65 they'd be around 9mm wide. If you insist on exact scale sizes nobody would enter those from '61 and would enter whichever car was the widest with the fattest tyres. The CSCRA rules allow a wider range. Don't forget you don't have to build to the maximum.



· Premium Member
3,088 Posts
Hi Stan,
I have to say this so many times but here goes again.
The dimensions are just minimums and maximums you don't have to build your cars to those minimums and maximums.
Build them to dead scale if you want to, whatever that means, bearing in mind that most cars get modified race by race and never actually race in exactly the same configuration twice.

For what it's worth my pet hate is a nice scale front engine car with an electric motor filling the cockpit where a full length driver should be.
Almost everyone, even the acknowledged concours experts, do it all the time and no one seems to notice.

You also have to remember that many of the people who enter these events have no idea, and not much interest in, what the exact scale dimension of any given car actually are. They simply want to race good looking models of historically interesting cars.

No set of regs is ever going to be perfect but so long as we get reasonable scale cars and a level playing field for racing I think that's the best we can achieve.
Push the scale side too far and we loose all the racers. Push the performance side too far and we loose all the scale modellers.
The balance seems pretty even at the moment.

As regards the Vanwall I think your dimensions are significantly out.
My calculations suggest something closer to 21mm fronts and 23mm rears.
The Model Cars plan also shows tyres of this size.
24mm fronts and 26mm rears are closer to the sort of tyre sizes fitted to the pre war Mercedes and Auto Unions.

Whichever way you decide to build your cars you're sure to find a welcome at any CSCRA race meeting.


· Tony Condon
3,014 Posts
Hi mick
a good point well made
thats all i am going to contribute

cheers tony
1 - 10 of 10 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.