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Conference terri::cars_uk

Title:Cars in the UK
Notice:Please read new conference charter 1.70
Moderator:COMICS::SHELLEYELD
Created:Sun Mar 06 1994
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:2584
Total number of notes:63384

1790.0. "Competition Preparation + Maintenance" by ESBS01::RUTTER (Rut The Nut) Mon Jun 08 1992 17:55

    A separate topic for any discussion(s) related to the preparation
    and maintenance of vehicles intended for competition use.
T.RTitleUserPersonal
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1790.1Some information to be considered ahead of timeESBS01::RUTTERRut The NutMon Jun 08 1992 18:0126
    First questions I have are :-
    
    	What are requirements for fire extinguishers in competition cars ?
    
    	What are the details for electrical cut-off and fire-extinguisher
    	switches to be mounted to the vehicle ?
    
    I know the answers to these two will be in the Blue Book, but the
    one I have is a few years out of date and I know some rules changed.
    
    As for the fire extinguisher, I know plumbed-in is needed, but of
    what capacity ?  Is an extra hand-held item also required ?
    
    For the cut-off switches, I believe that they must be operable
    from inside and outside of the car.  One common solution is for
    one part to be a cable pull, connected to the actual switch.  Is
    this still the general method used ?
    
    I think that it may be harder to fit a pull cable than to fit an
    additional switch in the cockpit area.  Would it be reasonable, at
    least for the power cut-off, to wire up two kill switches ?
    
    Back to the plumbed-in extinguisher, any comments on electrically-triggered
    versus mechanically-triggered installations ?
    
    J.R.
1790.2For what?NEWOA::SAXBYVote for Perot : He's got $3B!Mon Jun 08 1992 18:0610
    
    John,
    
    I can't answer your question, but I do know that the regulations vary
    from one form of motor sport to another.
    
    The conference will need to know what you're preparing the car for (and
    it'll satisfy my curiosity! :^)).
    
    Mark
1790.3I've got a new Blue BookCARLIE::MITCHELLEBeware of the green meanieMon Jun 08 1992 18:558
    
    If you'd like to borrow a 'new' Blue Book - get in touch....
    
    Even whre a plumbed-in extinguisher isn't compulsory, I'd strongly
    advise it (I'm sure the pros and cons have been discussed somewhere
    here)
    
    Elaine
1790.4ESBS01::RUTTERRut The NutMon Jun 08 1992 19:5222
    If you hadn't guessed, it would be the Stratos Kit that I would
    hope to use in some form of competition.
    
    Initial thoughts are that I might enter Sprints and/or Hillclimbs,
    as they are generally non-damaging (apart from driver error).
    
    It is possible that the Racing bug might bite, but that is prone
    to damage caused by other people on the track (isn't it, Derek?)
    as well as plain driver error again (always a risk, road or track).
    
    My other 'maybe' could be single-venue rallying, on tarmac events.
    This reduces the chance of other drivers causing damage, but
    probably increases my chances of driver error breaking something.
    
    Although it is what I am most interested in, I think that rough
    stage events are something that I will avoid, as that is almost
    certain to involve damage to the vehicle, with or without error.
    If I am to do this sort of stage rallying, I may choose to do so
    in a vehicle other than a Stratos kit - even though that is what
    the original car was made for, and managed very successfully...
    
    J.R.
1790.5some thoughtsOASS::BURDEN_D'24 Stude - The only way to TourMon Jun 08 1992 21:4829
Having done the types of competition you are thinking about (but not in the
UK), I can give you some of my thoughts.

Hillclimbing is fairly easy on the car, but still demands a high level of
preparation and maint.  Of course, if the road surface is rough, chances of
mechanical failure rise.

Rallying is tons more fun, but a different mentality is needed when you
purposely try to break the car, but still finish.  At least this is how I
classify getting the maximum out of the car.  To do that, you tend to push
some components over the edge, but hopefully they aren't the major ones.

With rallying, the kill switch is recommended to be inside the car, so it won't
get snapped off by some mean branch or tree as you slip off the road.  Saying
that, it should also be clearly marked and accessible from outside the car -
even if through a window or such.

Go for the plumbed in fire extinguisher with a big red button to push.  A
portable bottle might also be nice, but usually isn't required.  Remember, no
matter how good you strap in a removeable bottle, it *will* come loose in a
good crash.  Maybe put it in the trunk or something, to keep it out of the 
passenger area.

Start with hillclimbing (too bad you don't have some of the longer hills like we
do over here) and see how the car and you handle it.  Rallying is a natural
progression from there (either up or down, depending on how you look at it...),
but is a big step.

Dave
1790.6ESBS01::RUTTERRut The NutTue Jun 09 1992 09:207
    Next questions (well in advance) on 'preparation' :
    
    	Where can I get RTV sealant ?  (Room Temperature Vulcanising ?)
    
    	What about two-pack foam for filling panel/bulhead cavities ?
    
    J.R.
1790.7ESBS01::RUTTERRut The NutTue Jun 09 1992 09:3321
    Further questions, this time on fuel tanks.
    
    Rather than having plain fuel tanks, which would allow fuel to 'slosh
    about' quite a bit, what would be the recommended 'extra' to have
    fitted into the tanks ?
    
    First, foam-filled tanks.  How effective is this, does it reduce capacity ?
    
    Second, baffles in the tank.  These cannot be too effective, but will
    they be of any benefit at all ?
    
    Third, 'explosafe' added to the tanks.  Is this product still in use,
    is it worth fitting at all ?
    
    Fourth, having plain tanks...
    
    Any comments on there possible options ?
    
    Note that I do not intend fitting flexible fuel cells in the tanks.
    
    J.R.
1790.8another solutionCARLIE::MITCHELLEBeware of the green meanieTue Jun 09 1992 13:0116
    
    We've had to do a lot of work on our fuel tank, we were getting
    terrible 'pickup' problems, especially on long sweeping bends (Gerards
    at Mallory - for instance!). A lot will depend on the size and shape of
    your tank, and the position of the pickup. It is always easier to think
    about this at the design stage, rather than when you find problems! Our
    tank was already foam filled, which may have helped, but was not good
    enough. Baffles are not easy to add as an afterthought, since welding a
    tank which has had petrol in it could lead to the complete re-design of
    the garage! :-)  One solution you hadn't mentioned, which is used quite
    a lot, is to have a secondary small tank (about �litre) and two fuel
    pumps - so you feed the carbs from the small tank, which is going to be
    less prone to surge, and keep it topped up from the main tank. If you 
    want to have a look how it can be done - come and have a look at the '23
    some time!              
      
1790.9ESBS01::RUTTERRut The NutTue Jun 09 1992 13:4829
>>    the garage! :-)  One solution you hadn't mentioned, which is used quite
>>    a lot, is to have a secondary small tank (about �litre) and two fuel
>>    pumps - so you feed the carbs from the small tank, which is going to be
    
    I remember the discussions in here as to how this could be done.
    I didn't realise that it was a frequently used solution, but it
    seems quite reasonable that it should be.
    
    I am expecting to retain the fuel injection of the V6 engine, so
    things will behave differently as this uses a high pressure fuel
    pump and a return line for unused fuel (well, something like that).
    
    I will have twin tanks, mounted midships, either side of the engine,
    just ahead of the rear wheels.  I will have to consider just what
    form of pipework I will use for the supply and return lines.
    I guess I should have the return going to the same tank as the
    supply is taken from, so reducing the amount of flow that will
    have to go between the two tanks.
    
    Another question on fuel lines on a competition vehicle :-
    
    	How should the breather pipe be routed to avoid spillage in
    	the event of an overturned vehicle ?
    
    I would expect that a long line which contains a complete U-turn
    may suffice.  Again, this will be further complicated by the
    fitment of twin tanks.  Anyone know the 'correct' solution ?
    
    J.R.
1790.10which way....OASS::BURDEN_D'24 Stude - The only way to TourTue Jun 09 1992 15:5932
If you build a car for racing, go with the smallest tank you can envision,
that will allow you to finish the race (or go between normal refueling stops.)
If you want it for street use too, you'll probably want a larger tank
for convenience.

The racing fuel cells (foam filled) are very good for racing cars, not much
sloshing around, but the twin pickups and small tank like Derek has is a very
good setup.

These fuel cells usually come in set sizes and are square or rectangular.  If
you have odd shaped cells, these may not work for you.  Can you retrofit the
foam inserts into normal gas tanks?

Will there be a fuel line running between the two tanks to keep them both
the same level?  Maybe this would be a solution....


	---------		---------
	|TANK A	|		|TANK B	|
	|	|		|	|
	|	|		|	|
	|	|===============|	|
	---------	|	---------
			|
		    Fuel pickup point

This way you feed off the bottom of each tank, reducing the sloshing problem,
and both tanks drain at about the same rate.  You could also rig up a similar
return line, splitting it with a Y so both tanks get a somewhat equal amount
of fuel fed back from the f/i system.

Dave
1790.11Twin tanks + fuelVANTEN::ORTODell'Tue Jun 09 1992 16:0020
What is required by the blue book and what is prudent may be two different items.
A twin tank system is not simple to work successfully. But this is a working
system if complicated. The fuel injection system takes its fuel from a 1 litre
header tank. Each main tank fills the header via a separate low pressure 
pump with a separate return to each tank. Each return may be closed via a
solenoid valve.
Each main tank has a pickup at the rear and to the outside of the car. 
This would  allow you to run first one tank then the other. 
The venting system for each tank should in order perform correctly in all 
circumstances:
	1) Run so as to have a part of the vent pipe outside the dimensions of
the tank in each of the 6  directions( front, back, left, right , top bottom.
	2) Have petrol proof one way anti syphon valve with slow
backward bleed. A modified servo vaccuum valve can be used for this purpose.

I would suggest you contact in person someone, who has successfully overcome
competition fuel surge and venting problems, with your requirements


			Dell
1790.12.10 will not workVANTEN::ORTODell'Tue Jun 09 1992 16:099
.10 is not a feasible config since it will fail on the first sharp corner.
On a left hand corner tank B will let air in the line and so the engine
will falter. On a right hander
Tank A will let air in. 

		You need a logical OR
.10 		is a logical AND


1790.13ESBS01::RUTTERRut The NutTue Jun 09 1992 16:4521
�                  <<< Note 1790.11 by VANTEN::ORTO "Dell'" >>>
    
    Thank you, Mr Carburettor.  ;-)
    
    I will have to see how I can work something around your points,
    also I will discuss this with the kit manufacturer to see just
    what has been used for fuel injection on a non-competition setup.
    
    
    Re. Small fuel tank for racing,
    
    The fitment I intend using will be primarily for road use, so the
    large capacity would be a great bonus.  During the build of the
    vehicle, I wish to make allowances for anything that may be an
    advantage when the car is used in any form of competition.
    
    If the vehicle was to be a pure racer, then I would make different choices.
    
    Any further comments/suggestions ?
    
    J.R.
1790.14If I were to build a rally car...OASS::BURDEN_D&#039;24 Stude - The only way to TourTue Jun 09 1992 17:2628
What about spare tires?  Does the car have two different sizes, front and back?
What size will be carried in the car (in the front I presume)?  Will not
having both sizes in the car present a problem?

How good are the jack points?  Can you jack up both front tires from one
point, how about one side at a time?  Basically, how many times will you
have to jack the car up to change all 4 tires, 2, 3 or 4 times?

How about prewiring the car for a rally computer?  You can incorporate various
pickup points, both from driven and undriven wheels.

Install map lights, not switched with the ignition (same for the computer).

Wire an intercom for driver/co-driver.

Fit a toolbox somewhere for little tools.  I find this much easier than trying
to find a place for each tool.

Pencil/pen holders.

Make sure there holders inside the passenger compartment for little things
while driving or stopped after events.  Holders for water bottles (NOT CUP
HOLDERS! :-)), someplace snacks can be stored, etc.  Little things like these
make competing much easier.

CB radio or some type, maybe even a scanner for official race communications.

Dave
1790.15ESBS01::RUTTERRut The NutTue Jun 09 1992 18:3225
�                     -< If I were to build a rally car... >-
    
    Re spare tires
    
    Yep, car does have different tyre widths front and rear.
    Not a lot of space to fit spare(s) in the car.
    
    Re jacking points
    
    I intend to make sure that there are suitable points front and rear
    so that either end of the car can be jacked up very easily.
    
    One method I have seen for use when working on the car is for some
    form of 'adaptor' that you can fit into the top of a trolley jack,
    that then connects with two built in points underneath the
    bumper area of the car.  Same width fitting front and rear helps.
    I've spotted this in Ford factory-prepared rally cars.
    
    
    If I were to use the car for rallying, I would probably aim to do
    single-venue events.  This avoids many of the problems with
    servicing of the vehicle, and they are more often than not held
    on tarmac or semi-sealed surfaces.  Rallying is only a 'maybe'.
    
    J.R.
1790.16Anyone know details of brake balancing ?ESBS01::RUTTERRut The NutWed Jun 10 1992 09:3532
    Next subject - brake balance.
    
    I definitely want some form of adjustable brake balance built into
    the car, so I have two options available that I know of.
    
    
    1) Adjustable pedal box
    
    2) Adjustable device for reducing pressure in the rear brake line.
    
    
    The former uses a twin master cylinder arrangement and a movable
    'pressure point' where the pedal acts upon the pair of brake cylinders.
    This is what I would probably expect to use, if only because I know
    how it all works and I believe it is the most common solution.
    
    The latter option I know much less about.  It seems to me that the
    device will only be able to work up to a certain amount of brake
    pedal travel.  After that, I would have thought that the device
    would reach its compensatory limits and allow full brake line
    pressure to the rear brakes.  I have no idea if this could really
    happen, as I don't know any specific detail on just how it works.
    Of course, even if this could occur, the wheels may already be
    locked up all round, so would make no real difference.
    
    If someone can explain more about this second device, especially if
    anyone has knowledge of their use, then I would consider using it
    as it should allow me to use a single master cylinder with a brake
    servo, which would provide much easier braking most of the time -
    also a factor to consider as my Wife will want to drive the car too...
    
    J.R.
1790.17ULYSSE::CHEVAUXPatrick Chevaux @VBE, DTN 828-5584Wed Jun 10 1992 09:5015
    .16�    1) Adjustable pedal box
    .16�    
    .16�    2) Adjustable device for reducing pressure in the rear brake line.
    
    Use both. 
    
    Unless you're interested in something with good weight distribution on
    the rear axle (Porsche 911, Alpine, ...) you're NOT counting on the rear
    wheels to provide any reliable stopping power. On the contrary rear
    brakes are mostly used to put the car into a spin ... Most rally and
    circuit cars use very little rear brakes.
    
    In fact the device does not reduce the pressure, it merely limits it to
    a value that can be adjusted manually from the cockpit (adjustable
    valve spring).  
1790.18A jack for all uses?ARRODS::BARRONDSnoopy Vs the Red_BarronWed Jun 10 1992 09:5711
    re .15

    Have you considered the lever sort of jack, a bit like a wide sack
    barrow.

    Much more convenient on the sprint circuits, but of course it begs the
    question of what support vehicle do you intend using?  
    
    Then you'll need a trolly jack for home use :-)
    
    Dave
1790.19ESBS01::RUTTERRut The NutWed Jun 10 1992 10:3235
�    Unless you're interested in something with good weight distribution on
�    the rear axle (Porsche 911, Alpine, ...) you're NOT counting on the rear
�    wheels to provide any reliable stopping power. On the contrary rear
�    brakes are mostly used to put the car into a spin ... Most rally and
�    circuit cars use very little rear brakes.
    
    This would be on the Stratos kit that I am soon to start building.
    Therefore, it will have quite good weight distribution on the rear
    axle, as the engine is above/between the rear wheels.  Of course,
    this will not be as effective as a rear-mounted engine as in the
    examples you've quoted.
    
    I do appreciate that too much rear brakes will lead to a spin, but
    it is for that reason that rally cars are often built with more
    rear braking effort than needed for best stopping power, so that
    the car may be 'set up' under braking for a bend, making it easier
    to get the 'pendulum' effect commonly used for cornering.  This
    particular technique is not so usual on tarmac surfaces though...
    
�    In fact the device does not reduce the pressure, it merely limits it to
�    a value that can be adjusted manually from the cockpit (adjustable
�    valve spring).  
    
    Thanks, that makes sense.  I was imagining the device as some sort
    of 'reservoir' with a spring/damper arrangement, hence my thought
    that it could have a finite limit to its pressure compensation.
    
    
    Re 'sack-barrow type of jack'
    
    I had considered this idea too, as that is the style of jack used
    for single-seater type of race cars.  I'm not sure how much leverage
    would be needed for this to work at the rear of the Stratos though.
    
    J.R.
1790.20some adviceVANTEN::ORTODell&#039;Wed Jun 10 1992 20:0918
    in line brake balance adjusters do not usually have the range of adjust
    ment found in balance bar setups. Neither solution is cheap. �60
    for a good adjuster valve. 
    	I would install the balance bar.
    On the Gear linkage. If uses universal joints and these are of the open
    type, think again. These become sloppy and useless within 2000 miles.
    If the linkage must have UJs it is a false economy not to buy the APEX
    type �30+ each!. A duff gearlinkage can blow up the engine!
    Throttle cable:  You must buy a real competition quality cable, not one
    out of an imp or any such road car �25. Imp cable will snag if not a
    absolutely ideal run after 300 miles. The competition cables will work
    even if tied in knots.
    	Rose joints: Buy the stainless ones from Raceparts in Wallingford
    �25 each. The bronze  bushed ones become loose after 1000 miles.
    
    		enough for now
    
    			Dell
1790.21ESBS01::RUTTERRut The NutWed Jun 10 1992 20:4237
�    	I would install the balance bar.
    
    I am inclined to do this.  I also have the parts already, but may
    need to replace some of them before fitting.
    
�    On the Gear linkage. If uses universal joints and these are of the open
�    type, think again. These become sloppy and useless within 2000 miles.
    
    I'll have to see what I am offered.  There is a local company that
    has worked on a number of Stratos kits, including one which has been
    used for rallying (with a Honda/Rover V6 in it).  I will be having
    a long chat with them this weekend.  They have asked that I give
    them the chance to quote for any work that I have done.
    
�    Throttle cable:  You must buy a real competition quality cable, not one
�    out of an imp or any such road car �25. Imp cable will snag if not a
�    absolutely ideal run after 300 miles. The competition cables will work
�    even if tied in knots.
    
    Gerry sells cable sets, so I will have to find out what quality they are.
    
    I may consider fitting twin cables, but that has the built-in problem
    of increased friction - made worse by the long cable runs to be used.
    
�    	Rose joints: Buy the stainless ones from Raceparts in Wallingford
�    �25 each. The bronze  bushed ones become loose after 1000 miles.
    
    Rose joints come with the suspension components.  I believe that
    these will be of stainless steel.  I am told that the major one on
    top of the front upright is of the same spec as used in factory 6R4s.
    I don't know about the ratings of any of the other joints supplied.
    
    Thanks for the advice + warnings.  Anything I can find out now,
    without pain, will be much appreciated when I get down to the
    actual task of doing the build-up.
    
    J.R.
1790.22BrakesVANTEN::ORTODell&#039;Thu Jun 11 1992 14:4933
 Buy Mintex 171 pads    - good for both competition and the road
 Front ventilated disks - Brake fade is not funny 
 Use Dot 4 not DOT 5 brake fluid - Dot 5 gets too squidgy
 Buy a Stack tachometer -   most of the rest arent good enough (500+ rpm out)
 Buy a rev limiter
 Buy a big oil cooler  and thermostat - So its good for road
 High pressure oil lines use Goodridge braided hose with 
 the "not push on fittings" - is your engine worth more than �70
 Use only the top grade goodridge hose (Merlin motorsports will help)
 Think in advance where you can use wirelocking to good advantage particularly
 on the fuel system.

	Consider using braided hose on the fuel system. DONT use polythene
 Small gauge oil hose is best alternative to the real stuff.
 
	Your installation of the engine is down to you so you need as much
information as possible to know if it right. You  cant rely on smell cos the
engine will be in the back. This then means lots of gauges

 Oil temperature as well as oil pressure gauges
 Petrol Pressure gauge   - particularly with a "new" petrol system.
 The petrol and oil lines to the gauges MUST be braided hose not the nylon
 Fit a oil pressure switch  with a high setting 20 PSI. use a side indicator
 light  off a metro for the warning light.

	A good electrical installation is crucial to successful competition.

 Buy the dashboard switches from RS not the corner car accessory shop. 
 Dont buy the pre-insulated crimp connectors.

		Enough for today

			Dell