Roll Bars - Scrutineering Compliance

[Redneck Rocket]

So, to borrow a turn of phrase from my native Canada, I'm 'nickel and diming' my MKIV Spitfire towards the racetrack. Its not going to be quick and its not going to be pretty but at least I'll be racing. I'm not too far off now, I need the basic safety equipment - belts, harnesses, possibly a seat, and a kill switch. I also don't have a rollover bar. I've read up on the regs, and I know that if I race without a hard top, I only need a bar and not a full cage. This is what I'm planning on doing as it is cheaper, and because at 6'3" I barely fit in the car as is, and a full cage might be a bit too cramped. I've come across a few second-hand items on Ebay and the like, but I'm not clear on what specifically is required by scrutineering in order to pass. Obviously it needs to be installed properly, but in terms of the construction of the bar, what are the determining factors? Does it have to be cross-braced? Is there a minimum diameter? Basically, how can I tell by looking at an item whether or not it will pass the muster?

I know there are some details in the blue book, but I thought I would float the question here as people seem to know their stuff and I thought they might be able to give some advice.

PS - Anyone going to be at Stoneleigh tomorrow? If you are come and say hi - I'll be the tall chap in a black Classic & Sports Car fleece.

[simon drabble]

I will look out for you! re rollbar's you need to be able to take a straightline from the top of the hoop to the front of the car without your head interferring! If you make it triangular rather than a plain hoop you will create more rigidity to both car and hoop, that could be considered a win win scenario!

[Redneck Rocket]

Originally Posted by simon drabble

I will look out for you! re rollbar's you need to be able to take a straightline from the top of the hoop to the front of the car without your head interferring! If you make it triangular rather than a plain hoop you will create more rigidity to both car and hoop, that could be considered a win win scenario!

That could be a problem as I am one tall sonofa...! So if I find something second hand and it looks reasonably stout, I should be okay provided my head clearance is okay?

[Peter Mallett]

I think you'll find that for competion purposes the roll hoop, (this is usually the rear half of a full cage) must be triangulated.

[JimW]

Apart from recommending a through reading of the BB, I would suggest that you make contact with the club whose events you intend to enter. They are likely to be able to put you in touch with a friendly scrutineer who could advise you. Might cost you a pint or two.

Regards

Jim

[midgetman]

Redneck, this is something for one of the Triumph clubs to get involved in, they'll have experience and may even have people selling 2nd hand ones. I'm a Stoneleigh on the FISC stand A50, I'll be the (also tall) one in the navy racewear.co.uk sweatshirt.

[AndyV]

There will be some Spitfires racing (mine included) at Silverstone on Saturday the 31st March 07. If you can come and have a look at what we have fitted (there is a variety of types) and have a chat, actually seeing fitted hoops/cages is a million times easier than explaining it online.

Most of the commecially avaliable roll bars for spits are quite low so the cars need some work to ensure your head stays below it (I'm 5'10" and have the floor lowered 2") so you need to check this before spending your well earned. Or you could get the tubing made up to suit your height. Lots of options, best to come and have a look, I'm the topless black and Silver Spit No50.

Andy

[AndyV]

Who are you intending to race the Spit with? the TR Register/TSSC runs a championship for Triumph Sports cars of various classes of tune.

Not sure if you have done this already but it will be worth a visit to the Triumph Sports Six Club (TSSC) racing messageboard where many Spitfire (and GT6) racers frequent. They (we) will be all too happy to help bring another Triumph onto the track. Google for TSSC.

[retro_msport]

On a safety ground i would say 38mm CDS with a wall thickness of 3mm as a minimum (BBrules) you can go lighter on the wall thickness if the diameter is increased, (detailed in the BB)

The height of the main hoop has to allow your head to pass under a line to a substancial member infront of the driver (not the fibreglass body/bonnet)
I would go with a main hoop and 2 backstays with a diagonal as a minimum, but the others have suggested the best route, speak to the clubs

[Mik]

My spitfire also has a lowered floor to accomodate my height. The alternative I've seen is to fit a roll bar/cage that is higher than normal above your head. At 6' 3" you'll probably need to do both however.

As AndyV says, come along to one of the TRR/TSSC races and have a look what other people are doing. It's a common problem as the spitfire isn't that high to begin with. I'd expect that anyone taller than about 5' 8" -ish is likely to have problems without modifying something.

Current calendar can be found on the championship website

[Redneck Rocket]

Thanks for all the help/suggestions everyone. It sounds very much as though I'll have to get someone to fabricate something for me. I was hoping there might be something available that could be bolted in but I guess I'm too sodding tall in too short a car! I'm not really competent enough to do something like lowering the floor so I'll have to go with a really big hoop.

AndyV & Mik - I will definitely come and have a poke around. My friend Colin runs the Thoroughbred Sportscar Championship and I think the TRR/TSSC races are often on the same cards. In terms of where I was going to race, I haven't made my mind up yet. My car will be pretty slow:

Fast Road springs/shocks
Full manifold and exhaust system
Fast road 83 cam with duplex timing chain
Trumpet intakes on 1 1/4" SU's
13 Row Oil Cooler
Kenlowe fan (and fan taken off the engine)
New, but not terribly expensive road tyres

Apart from that it will be pretty much standard, and without any real lightening carried out. I was thinking about the TRR/TSSC championship but I think that my car would be too slow and I don't want to be way off the back of the grid. I was considering the HSCC 70's road sports because modifications are very restricted and there is a sub-1300 category.

[Alan Morgan]

The HSCC have a lot going for them - you would certainly get to race at some nice circuits. I think I'm right in saying that the guy who does most of the winning in 70's Roadsports drives his Spitfire to the circuit, towing a trailer containing his spares and tools behind the racecar.

[Mik]

Originally Posted by Alan Morgan

I think I'm right in saying that the guy who does most of the winning in 70's Roadsports drives his Spitfire to the circuit, towing a trailer containing his spares and tools behind the racecar.

Yes, you'd be right there. He's done his share of winning in the TSSC championship as well.

Redneck: your car sounds quite similar to mine, except I have lost some weight from the car too (much easier than losing it off me ). Lowering the floor didn't need too much competence. Just an ability to wield an angle grinder, jigsaw, hammer and welder (I'm better at the first three than the latter!).

Come and say hello at one of the meetings.