A few questions just in-case anyone knows the answer, or can point me in the right direction.
Spare wheels - I knew where I was with Class 7 regs - they tell me precisely where I can put the spares. Any other class, say class 5, I can't seem to find much - yet I've seen all sorts of cars with spares on the boot lids etc. Are there any regs regarding positions?
Suspensions - rules state that original mountings, spring positions much be used, although additional shocks, springs and linkages can be used. So if I leave the mountings alone, can I "adjust" other aspects of suspension arms - lengthen, shorten, twist them? A potential competition car would need a few "tweeks" to get it's bum off the ground!
Bri
Bri - The spare wheel thing is on page 13, para J76. ".... may not extend rearwards mre than 200mm from a vertical line passing through the rearmost part of the original bodywork (excluding bumpers), or more than 100mm beyond the rearmost part pf the original bumper postition ...."
ReplyDeleteRegarding suspension perhaps Simon will see this and clarify.
Michael
Now somebody has brought up the subject of spare wheel location perhaps the elders of the sport could explain why there are apparent anomalies in the ACTC specifications for Class 7 cars when compared with the MSA Blue book. The Blue book states that spare wheel carriers on Class 7 cars can extend 400mm beyond the original bodywork. Why then do the ACTC specs state that Marlin wheel carriers can extend 400mm beyond the rearmost part of the chassis, some way aft of the bodywork? However, Dutton Phaetons are not supposed to have rear mounted spares at all, Melos (which share the Phaeton chassis) can only extend 270mm beyond the bumper which is a lot less than 400mm from the bodywork and the dimension for the Vincent is 330mm from the bodywork. Why do the MSA regs not apply universally? Since a spare wheel carrier is the same as a luggage rack the rear overhang should be irrelevant - shouldn't it?
ReplyDeleteAs a rough and ready response to this thread, the crunch is that spare wheel locations for Class 7c cars are controlled by the specification for that car. For suspension mods I would draw attention to; and without looking it up a note that certainly used to appear in the Blue Book, and I paraphrase
ReplyDelete"Unless the rules say that you can, then you can't"
Thank you for that. I had already read the ACTC website extensively. I was wondering if there was some easily definable guiding principle in establishing these specs. Maybe it is just too complicated for this forum.
ReplyDeleteThanks Michael! Maybe I ought to have read and inwardly digested the newly arrived supplementary rule book as well as the Blue Book before putting fingers to keyboard! Seems pretty clear to me. I asked about suspension mods as I've seen some interesting views on the use of "standard" locations on quite a number of vehicles . . . ;-) Graham - Dutton Phaeton spec sheet specifies the spare wheel(s) position as on the boot lid and protuding no more than 200mm from the rear of the car. The apparent anomaly in spare wheel positions, boxes etc annoys my usual passenger . . . I just usually drive past where the Marlins tend to stop :-) so it doesn't tend to worry me much. I think you can have too much rear bias - we tweaked the Yeller Dutton back a touch from where we got to at one point, even to the extent of front ballast too! I reckon we've got it pretty good now, especially if yu get a bit of a bounce going on a section - as it bottoms out on the shocks and rams the rear wheels into the ground, you can feel it dig down, grip and go - most pleasing everytime it happens - thinking of the deep mulch in the last sections of the March Hare. Bri
ReplyDeleteAhh but, if one stuck to the concept of 'if it doesn't say you can, then you can't', one would be at a disadvantage as I know of many indiscretions that go un-penalised. It would be unsporting to mention them publically but they include obvious suspension changes and spare wheels moved from the nose to the boot. Even when sticking to the rules there are some features allowed on some class 7 cars that are not allowed on others. I gnash my teeth every time I see Marlins with two upright wheels protruding from the rear whilst the Dutton has to fit them flat on the top of the boot lid. With the leverage gained from moving the spares upright to match the Marlin a Dutton could reduce dead weight ballst by some 50lbs, giving it the usual traction but lighter so better on power sapping hills. The bodywork overhang is irrelevent, the leverage of ballast behind the axle is the issue. Liege and Dutton for example have no gap between the rear of the road wheel and the leading edge of the spare wheel. In fact they overlap by some 8". I've not measured a Marlin but the same dimension must be two feet, a considerable advantage must be gained by hanging two spare wheels out the back by two and a half feet more than others in the same class. Does this make me a contender for The Grumpy Old Beggars Club, I've got the sticker on my MPV so it must be true.
ReplyDeleteYeller dutton (sorry not sure of your real name) please spare your teeth by considering this...whatever the theoretical advantages of marlin spare wheel placement, how often do marlins beat duttons in class 7 these days?
ReplyDeleteDutton Phaeton S3 and S4 share a chassis with the Melos. Cars in the Dutton Owners Club often have no spare wheel but if they do it is vertical (Phaeton) or slanted (Melos) at the rear. Why then do they have different spare wheel locations in ACTC specs? The cars in my original list are all notable for having spare wheel locations different from 400mm behind the bodywork.
ReplyDeleteI guess that if you have a Dutton and feel disadvantaged about the spare wheel positions you could ask class 7 co-ordinator Pete Hart to change the spec, explaining the reasoning. I'm sure he and the committee would listen to any reasonable argument and if they couldn't go along with it explain why. - Michael
ReplyDelete99% of Marlins are uncompetitive against 99% of Duttons (both types) as it is. If the spare wheel / toolbox specs were to change as suggested above, then the gap would widen still further. Does everyone want all the Marlins to disappear? Don't all shout at once. Andrew
ReplyDeleteSteady on, I meant no harm and was only inquiring for the sake of interest. I studied all the available kits in the 70s because I wanted a project. I rather liked the Marlin but it was Triumph based in the early days and I was a Mini enthusiast. Also there wasn't enough leg room for me. I recall that Marlin did use trials success in their marketing even then though - not that I was aware of trialling at that time. I thought Duttons were a bit cheap and nasty (and ugly). Years later it interested me to see which kits became popular as trials cars and which didn't catch on. For instance when was a Siva Edwardian Roadster last spotted? Why do Marlins outnumber Duttons when the latter are so much cheaper? Then I studied the ACTC specs and wondered why there were detail differences in the permitted modifications and this thread seemed like a way to find out more. It hadn't occurred to me before that this was a form of handicapping.
ReplyDeleteMarlins outnumber Duttons because (a) there are far more of them around, and (b) they offer pretty near bombproof wash-and-go classic trialling for anyone who wants a bit of fun and isn't too worried about Awards and Championships. The "problems" start if you want to make a Marlin competitive in Class 7, and if you want chapter-and-verse on why, just email me "offline". Handicapping is "the truth that dare not speak its name" when it comes to the Class 7 specs. It's not really appropriate to continue this theme in a thread devoted to "spare wheels and suspension mods" but I think you have hit-the-nail-on-the-head. Hence the reason why ... the Class 7 Dellow spec is VERY tight ... the Class 7 Liege spec has recently been relaxed for wheel size ... the Class 7 Marlin spec allows for a lot of weight at the rear to compensate for the weight of a B-Series engine at the front ... etc. etc. But, and it's a VERY big but, discussion of Class 7(c) specs is irrelevant when kit cars in general (except Dutton Meli driven by Andrew Martin) are generally beaten by the "modified beyonds" - just look at the Class 7 results for 2008 events. Andrew
ReplyDeleteNearly irrelevant - we've equalled the top Class 8 on one of the easier trials last year (and only lost overall on the special tests by a few seconds), and beaten a large part of the class on others. A little bit less overall weight, but maintaining the balance and we might have been closer. As I mentioned elsewhere, I'm contemplating a few mods to the class 7 Yeller Dutton that will take it into Class 8, rather than pretend and hide in class 7. I have to say I probably enjoy the tweaking/modifying/improving more than the actual sections - assuming they are worthwhile and do actually make a beneficial difference. Carry on with any discussion on this thread - I've got the answers to my original question, and it makes for an interesting topic. Bri
ReplyDeleteNow that I follow the argument for hadicapping, and very sensible too, in my recently revised opinion, the comment regarding ''modified beyond' cars from class 5, I would guess, describes those with flat undersides gained by using VW gearboxes and 15" wheels. The biggest sticking point for the Dutton is that the diff catches when the 14" wheels are in deep ruts. This is a vastly significant and unavoidable ground clearance difference between the two designs of some four inches. As the kit cars are equalised by using very similar running gear, perhaps the 'modified beyond' cars should go straight to class 8? If we put a VW engine and gearbox into the back of the Dutton, or otherwise gave the kit cars a flat underside and big wheels, we'd expect to go straight into class 8. Perhaps a compromise of homologating a back end that does not so easily catch on the hump between ruts would be a way forward? Regards to all, John Rhodes
ReplyDeleteNOW I get it. Wonderful how a nights sleep and an email from co-driver/driver John (YellerDutton) woke me up to your point - the other classes "modified beyond" class limits that end up in class 7 with more ground clearance, more power and more grip. Not the class 8 specials. So, a further read of the rule book re-confirms original springing system and springing points must be retained in operational use - except classes 7(a) and 8. So say you take a RERWD car from a "lower" class and sling in the complete back end from bigger, more suspension travel RERWD car. You've not caused any problems with the above rule as you've moved into class 7(a) - but surely, as the rules don't say you can change the actual suspension arms, you've just jumped into class8 - not 7(a). Plus - J69 - the position of the engine mountings chassis may not be altered . . . so again, the above conversion sticks you straight into class 8? As for J62 . . . I have a number of tape measures for sale for those really with the bit between their teeth - and no tolerances are mentioned in the book . . . hmmmm? Bri
ReplyDelete