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MG Midget and Sprite Technical - Scruit question for Daniel -Purists DON'T look
Last race at Mallory the scruits didn't like my door bar - bolted to a box section, see first pic: I had to promise to sort it out for 2010 otherwise they won't let me race it.. so I've re-bolted it to the cage, see second pic. This put it level across the door - great for side impact protection but harder to get in and out. Fortunately I'm slimmer than my two brothers but will it be ok to race like this? |
Steve Collinson |
2 pics obviously doesn't work...this is how it was:
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Steve Collinson |
My personal opinion as a Spridget enthusiast: From the 2010 Blue Book Page 274 and para 19.14.3 requires you to have a door bar if you have a lightened non standard door. Generally I think the interpretation is that a standard door lightened falls within this para! My personal view is that the weight saved lightening the door is less than the weight added by the door bar so not really worth the bother. A strict reading of the instructions is that your car has standard doors that have been lightened and so falls outside 19.14.3. On the other hand I'm assuming your door is steel with the guts cut out rather than a fibreglass door. I wouldn't recommend your debating this with a scrutineer as any worth their salt will find something else your car doesn't comply with where there is no debate.... But I might be wrong - you probably have more experience of this than I do. Page 165 para 1.3.5 b refers to drawings K9 and K12. while para 1.3.7 refers to drawings K21 to K30. What you've done doesn't really fit with any of those drawings which is fine if your door bar is certified as a 'free design' by a cage manufacturer, which yours isn't. So my question is did the Scrutes advise you to improve it for your own safety or did they advise you to get it to conform to the regulations for your own safety? If it were my car I'd get out the scales and weigh a bare standard door, the lightened door and the bar and do the sums. My recommendations are to either fit an un lightened door (with or without the weight saving/penalty) or get the cage modified by a manufacturer with a better door bar arrangement, especially the bracket to fix to the front section and the diameter of the bar itself. The advantage to the latter solution is that done correctly you'll stiffen the whole shell which can only be a good thing. I'll stay clear of your car in scrutineering assuming I recognise you in time but feel free to grab me when I'm prowling in the paddock. Finally, in case you're following the trunnion or thermostat housing threads - even I'm not recommendingn stainless steel for this one. Always interested in what anyone else thinks or their experiences. |
Daniel Thirteen-Twelve |
And the unmodified or standard door, do they mean the early one or the later one with the extra steel plate? |
Alex G Matla |
Daniel - Thanks. It was picked up at Mallory, no other scrute mentioned it at earlier races, but I see their point. Firstly the door is fibreglass, so yes, lightened. What they didn't like was the fact that the door bar was bolted at the front end to a smaller box section (as in the second picture) They maintained that it should be bolted to the cage itself. I was just advised to change the connection arrangement. So what I have done is to change the angle of the bar and as per the 2nd pic it's now bolted to the cage. My query is not so much about the size of the bar or how it's bolted (both imo are now fine) I'm not sure whether it's now too high. I can get in/out ok but need to have a go with my helmet on. Is there some 20sec rule? |
Steve Collinson |
Fibreglass door is non-standard so it needs the door bar. Yes the door bolt should be bolted to the cage. It does look high and isn't bolted to the cage with an approved fixing... Scrutineers tend to see more crashed cars than competitors and sometimes have to write up a formal accident report on the damage to the car. It's that experience that in part can create the difference in opinion between what's ok and what's not. Without checking I think its 5 seconds! |
Daniel Thirteen-Twelve |
Hi Steve Your door bar was what Safety Devices laughably called their 'universal door bar' - the fixing to the cage is as the original kit - the only modification I can see from the manufacturers design is the welding which has rendered the bar too short so you have to fix it at the top of the door aperture - usually they slope down from the rear main hoop to somewhere nearer the bottom of the door aperture (which has the advantage of allowing you to get in and out). Whether SD have modified their design of door bars recently I know not (to take into account MSA regs) - might be worth contacting SD... But I would be inclined to get a proper door bar welded in by a cage manufacturer. Having now had 2 fairly significant impacts in the drivers door while racing (the first at Dijon was a real doozy...) I would not advise anyone to race a Spridget without at least a drivers door bar - whether you run a standard door or a lightened one... James |
James Bilsland |
My car had the SD 'universal' door bars, which - as James said - were angled down at the front (see pic). Also as James said, whether the door is lightened or not, I wouldn't even think of racing a Spridget without a door bar. |
Dave O'Neill 2 |
"Having now had 2 fairly significant impacts in the drivers door while racing " James/Steve, ever considerd driving a LHD, have the right"passenger side" as a crash-zone for when you get hit on the right again... :) Okay, ill get my coat.... |
Arie de Best |
One of the reasons I drive "topless" is that I can't climb into the car wearing a helmet without my head poking out over the roll cage. The door bar makes it very difficult but I feel a little less exposed as the midget is very snug around me. Mind you, pelvic injury beckons if I'm heavily T-boned. Reading this thread and Andrew McGee's comments elsewhere about welded in cages makes me think I'll be doing something different to mine in the near future. Dave - did you weld the clamps we can see on the cross strut? |
Max max-at-midgetmax-dot-com |
Max - Yes, they were welded, although not by me. |
Dave O'Neill 2 |
Cheers all. Plan is to replace the bar, bolted and welded. James - let me know when you want to come over to the pen. |
Steve Collinson |
My car had an alloy door bar(not legal anymore) in an "s" shape that allowed it to be bolted in using the Aleybar type clamps as shown in Daves picture.I thought about having a steel one done to the same profile.
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m fairclough |
Arie Statistically speaking I am now more likely to get hit on the nearside (LH side) of the car so i think I will pass... If you can work out how to set up a central driving position (a la McLaren F1) I may be interested... :) Seriously though LHD isn't ideal for racers in that most circuits in the UK (and in Europe) are clockwise... Steve Are you likely to be around this weekend? I don't think I have your number - mine is 07976 930570 James |
James Bilsland |
This thread was discussed between 17/01/2010 and 20/01/2010
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