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Discussion Starter · #1 ·
Following on from the recent survey (see previous thread).
Proposals below for extending the GP classes which currently end at 1976.

Class 7 1977-1982 Formula 1 and Indy Cars - The 'Ground Effect' cars.
• Inline motor orientation only
• Front wheels and tyres: Minimum diameter 17mm, minimum width 8mm
• Rear wheels and tyres: Minimum diameter 19mm, maximum width 14mm
• Minimum ground clearance 0.5mm
• Track dimension must be 1/32 scale within + or - 2mm but must not exceed a maximum overall width of 68mm

Class 8 1983-1988 Formula 1 and Indy Cars - The 'Turbo' F1 cars.
• Inline motor orientation only
• Front wheels and tyres: Minimum diameter 17mm, minimum width 8mm
• Rear wheels and tyres: Minimum diameter 19mm, maximum width 14mm
• Minimum ground clearance 1.5mm
• Track dimension must be 1/32 scale within + or - 2mm but must not exceed a maximum overall width of 68mm


I don't think there is anything controversial about class 8 as it's basically the same as our existing class 6.

Class 7 however is a little more difficult.
As you will all know the 'Ground effect' cars ran with no ground clearance at all under the side skirts.
This is probably impractical for slot cars.
I have suggested a minimum of just 0.5mm which for those of us used to running BSCRA cars is not unusual.
However, what about tracks with copper tape or plastic track (as planned by Gary), would 0.5mm be impractical or even harmful to the tracks?
Your input will be helpful.
The other thing is the start date of 1977. There was only one 'Ground effect' car in 1977, the Lotus 78.
Should we therefore add 1977 to class 6 and start class 7 at 1978 when others started building these cars?
Again your input is invited.

The more of you that make you views known the easier it will be to make the correct call.

Cheers.
****.
 

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Gary Skipp
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Great, I think these two classes will be excellent additions!

My feelings with regard to ground effect cars would be for the chassis to follow the same 1.5mm rule as turbo cars, but with no limit on the body shell. If people want to build their own skirts with something like a daylight gap then that should be allowed. I can't imagine body materials being harmful to the track, and if it did end up dragging then the friction would be harming the driver. It should be straightforward enough to seperate what is a 'chassis' from what is a 'body' but if we felt a rule needed to be written then I would suggest something along the lines of any part of the car directly connected to a load bearing support (ie, motor mount, axel carrier, guide fitting) is regarded as the chassis.

Not entirely sure about the 17mm min on fronts but I trust your judgement over my non-backed reservation.

In favor of extending class 6 to 77.
 

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Hi Miick.
I would extend class 6 to 1977.
.5 mm G/C is a bit low for all but the flatest of tracks, why not compromise at 1mm? If you state .5mm as the limit some folk will build to this no matter what track conditions prevail. Class 7 will still have the potential to lap faster than 8, is this historically correct for the 1.1 cars?
 

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I've been racing on wooden tracks for some decades with 0.5mm ground clearance and it isn't a problem. Even with quite bumpy tracks 0.5mm is OK, in fact I haven't come across any wooden tracks on which 0.5mm would not be sufficient, but perhaps somebody else knows of some bumpy ones I've not seen?

Wooden tracks with flat out bankings may well require more ground clearance to stop the cars decking as they enter the banking. There are very few of these tracks in the UK, are any CSCRA run on these tracks?

Ground clearance might be a problem on plastic track.
 

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Gone racing.
We race on all sorts of track, some of them sectional and de-mountable. I have raced on tracks with joints more than .5mm high!!
regards Bill.
 

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David Collins
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Gary, I feel that for sake of quick scrutineering and ease of understanding the requirements of the regulations we should stick to an overall ground clearance rather than a separate one for chassis and body. That has the potential for endless confusion and argument, just at a time (i.e. before racing) when you don't want it.

With regard to an earlier thread about plastic tracks, Ninco can get pretty bumpy, and my view is that we should set a clearance which should work for most tracks. This is because the primary aim of the CSCRA car standards is to provide one common set of rules, so enthusiasts can build a car which is eligible for a number of events.

David
 

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Gary Skipp
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For a blanket GC I suggest we stick with 1.5mm. The chassis tubs themselves weren't on the deck so the model's shouldn't be either.
 

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A couple of comments ****

1. I agree with Gary's first post about ground clearance.

2. Where is there an good comprehensive source of track dimension information for these years? The Betta list is a good source for wheelbases and the SM Cars site has a good, but not fully comprehensive, collection of plans. A lot are Roger Taylor 1/24th plans which are scaleable but a lot are from Tamiya etc kits. Given the wheelbase it should be possible to work out the track from these, but a good comprehensive list would be better. I don't mind collating such a list if people can feed me information.

3. Is 68mm too wide for some of the tracks we use? For example what are the lane centres of the Wellingborough 4-lane circuit? Netley lane centres are 3.75" and the Falcon F1s at 68mm get a bit hairy. How many cars from these years actually scale to this width?

4. Year groupings are fine.
 

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I just put a steel rule across some of my 70s era Scalextric F1s and most seem to have a standardised width across the rears of about 63mm, although the Ferrari 312T is 67mm. This is quite big, the new Scalextric Start generic LMP is "only" 61mm and before I measured it I expected that to be amongst the widest of plastic cars. 63mm is 2.5" which I've come to regard as the widest practical size for a 32-scale car as it's the width of the all the production and 32 Eurosport chassis.

I haven't driven one for a while but isn't a BSCRA F1 quite a long car? That would make the width even more of a handful when running alongside other cars in the corners. Open wheels, long w/b, 68mm wide - no wonder it's a crashfest!
 

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Hi Dick.
A quick scan on the popular F1 websites came up with these specs; 1979 year.
Ferrari 312 T4 O/A width =2120mm (66.25mm).
Lotus 79 O/A width = 2146 mm (67.06mm)
Lotus 80 O/A width = 2134 mm (66.68mm)
The Williams of that year I can only find a track figure for, but with the same width tyres as the Lotus, would be wider than the '79
Assuming our 'scale' tyre width of 14mm (17.6 inch) is right, then a maximum width of 68mm would appear be correct.
Regards Bill.
 

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David Collins
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We run an F1 class at Wellingborough which is dominated by the SCX F1 cars. We can run up to 70mm wide in this class, and while there is the usual tangling that you get with open-wheel cars, I don't think it's perceived to be a problem by club members. Although I think our Scalex track may be 4" centres. **** is racing at the 1/32 club night tonight (i can't - childcare :-() but will no doubt correct me.

David
 

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Hi all,
Just to clear up a few queries.
Lane centres at Wellingborough are 3.5inch and, as Dave says, we don't really have a problem running F1 cars 68mm+ wide.
We have even raced BSCRA Falcon powered F1s on there without too much problem. Just don't try to go around the outside of another car.

Why 68mm?
F1 cars were limited to a maximum width of 2150mm from 1976 until 1993 which works out to just over 67mm in 1/32 scale.
The current Class 6 (1971-76) limit is 68mm so there would seem no logical reason to make the later cars narrower.

Best source I've found for F1 cars of this era is;
'The Camel Complete History of Grand Prix Motor Racing' by Adriano Cimarosti.
My edition was published in 1986 and translated into English in 1990.
It lists the principal dimensions of every F1 car from 1971 to 1989.
So if any one wants to know about any particular car just post on here or PM me.

17mm minimum diameter front wheels?
Again this is carried forward form Class 6.
It is also the exact size of the front tyres fitted to the 70's and early 80's Scalex F1 cars. From the Ferrari 312B of 1971 to the Williams FW07 and Brabham BT49 of 1981.
The recent Scalex McLaren M23 and Ferrari 312T are fitted with tyres less than 16mm diameter but they look too small to me.
I do realise that the Tyrrell 6 wheeler had smaller front wheels.
The later Turbo cars did use bigger diameter front tyres so maybe we should make the minimum 18mm for them.
Your input is welcome.

I too like Gary's idea about ground clearance.
1.5mm under the chassis but the outer body sides, between the wheels, can be lower than this.
This should protect our tracks but still give the correct impression of a 'Ground Effect' car.
Do we need to have a minimum clearance for the body sides or can we say 'the body sides must not touch the track in normal racing conditions'?

Cheers.
****.
 

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QUOTE Best source I've found for F1 cars of this era is;
'The Camel Complete History of Grand Prix Motor Racing' by Adriano Cimarosti.

How have I managed without this book for so long? I must have one.

Thanks ****, I suspected that you would not make suggestions without sound evidence to support them.

Now to search Amazon......
 

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I started thinking about building chassis for these new classes and immediately remembered that the following appears at the top of GP and Indy Car section.

"Any GP or Indy car which has side tanks/fairings between the wheels must have
these mounted as part of the body and must not have any part of the chassis or any
ballast under or in these tanks/fairings."

The question is do we wish this to continue to apply to these new classes where a consistent feature of the prototypes are such side tanks/fairings?

I have always felt that the restriction is justified in the periods where such features where rare , such as in the 1952-1960 period when there was only the Lancia D50 plus a few streamliners or the 1966 to 1970 period where there was only the McLaren M7B. There is a generally held slot-racing truism that weight out wide between the wheels helps handling so without the restriction everybody would tend to build the same side-tank cars detrimentally reducing the variety of the entry.

When all the cars of the era have side pods (with the advent of the ground effect era they tended to be called pods) this advantage leading to loss of variety disappears. It is also a bit difficult to decide where the "body" finishes and the side pod starts, especially when looking at the underside of a slot car and trying to decide whether the chassis is under the side pods.

In the early 1970's when ECRA was the only body in the country trying to regulate competitive slot racing, the issue was dealt with by limiting the width of the chassis to 1.25" (about 32mm). Should we do something simlar for these new classes?
 

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Gary Skipp
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I think a width limit is probably the easiest thing to regulate.

In the case of ground effect cars, there wouldn't be a chassis out there anyway!

BUT

For the later turbo cars there may be some cases where it would be useful to have your chassis out in the sidepod as something to put a radiator/similar detailing part on to. Plus, these cars were fast! So they should benefit from a wider chassis. Its going to be a grey area though because pan sizes could easily get out of hand. Perhaps you could specifiy that any part of the chassis should not extend beyond the sidepod to be visible when viewed from above?
 

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Discussion Starter · #18 ·
Looking at the available RTR cars for the post 70 period most of them have a chassis that extends to the full width of the car.
On the Turbo cars the chassis will include the rear diffuser which will certainly be visible from above.
Many people will use these RTRs as the basis for their cars, and very good they are too.
In view of this I think that we should not apply a chassis width restriction to these cars.

I would also be reluctant to retrospectively apply a maximum chassis width for two reasons;
1. It could make some currently legal cars illegal.
and 2. It could lead, as it did in ECRA days, to people making bodies that are way over scale width in order to fit a maximum width chassis.

Maybe the simplest solution would be to apply the existing rule only to classes 1 to 5 (all the classes up to 1970).

Cheers.
****.
 

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QUOTE Maybe the simplest solution would be to apply the existing rule only to classes 1 to 5 (all the classes up to 1970).

I agree ****, especially now you have enlightened me about the chassis under the available RTR's of that period.

QUOTE Perhaps you could specifiy that any part of the chassis should not extend beyond the sidepod to be visible when viewed from above?

Gary the rules already cater for this. Look under 2. Bodies. There is also the basic rule under 1. Scale and Dimensions" All cars to be accurate 1/32nd scale representations of a full size car" which can be used if anybody starts Extracting the Urine with very wide side pods.
 

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Discussion Starter · #20 ·
We have revised the GP Car Standards along the lines discussed in this thread.
We have also added a few 'clarifications' which are not changes as such but just make certains things that most of us take for granted into clear requirements.
David has now added a new page on the CSCRA site entitled 2011 Car Standards.
Please take the time to read it carefully and let us know if there is anything wrong, unwanted or undesireable.
Please keep this thread only for the GP classes.
Cheers.
****.
 
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