Offroad Racing a Defender - Ideas please!

[Treads]

I've caught the offroad racing bug and am thinking about building my own car My thoughts are to get a wrecked or blown up tdi200/300 defender, strip it out and convert it to a V8

So now I've got some decisions to make:

A) What model Deefer?
110 Cab chassis - Easy to get; but not much cab length.

110 Wagon - Easy to get; but harder to convert to something usable

110 Hard top - Hard to find; but much easier to convert

110 Ute back - Perfect!; but where do I find one???

90 Hard top - Hard to get; not sure about directional stability at speed?

90 Ute - Impossible to find in AU? Directional stability?


4wd or 2wd?
If I want to run class 5 what would I need to do to convert it to rear wheel drive only? How much weight would I save ?

C) Which motor/gearbox combo?
3.5? 3.9 ? 4.6? Carbies or injected?

Anyways, lots of things to think about

more to follow...

[uninformed]

can you give more details on class 5?

kind of pointless getting a 4wd LR to race in a 2wd class...all that extra weight of Tcase and front difff etc etc etc etc to sort out without using it....

if racing in a 4wd class:
Id use the 110 cab chassis. Its wheel base will help with speed. Id redo the front and rear links. Using the same types but redone to suit speed. shocks will play a big roll....$$$ will get you there. Motor I would push back as far as possible. keep pushing all weight back if possible. get rid of tray and custom tube rear end, incorp a cage.....widen wheel track...TT's run about a 1.6-1 ratio of wheelbase to wheel track....If you have more $$$$ look at wildcat engines (rover based)

good luck with it

Serg

[THE 109]

There's a Bowler tomcat on ebay at the moment which might just fit the bill.It's in vic.

Cheers Eric

[Pedro_The_Swift]

2wd Performance Class
(from the CAMS manual--)
SR 2.1.2 COACHWORK
(i) The original silhouette of the coachwork of the vehicle, when viewed from the side, must be retained and may not be changed from the vehicle from which it is derived, except as specifically permitted below:
(a) the bodyshell (see Definitions, “General Requirements for Cars and Drivers” in the CAMS Manual of Motor Sport) must be unchanged in material;
(b) bumper bars and external decoration may be removed. The body must present a neat and professional appearance;
(c) coachwork beneath the bumper bar mountings may be removed between those mountings and the centre of the corresponding wheel;
(d) a bull bar/brushguard not exceeding the width (at the front) of the bodywork may be fitted;
(e) front and rear stone trays may be removed;
(f) the radiator grille must remain unchanged in shape and must remain in its original location;
(g) the fitting of equipment and/or ancillary mechanical components in the cargo compartments of utility/pickup-type vehicles is permitted, provided that this does not alter the silhouette outside the area bounded by the rear of the cabin, the top of the side panels of the rear cargo area, and a straight line drawn from the top of the tailgate to the rear of the roof;
(h) the maximum permitted variation of the wheelbase from the manufacturer’s specification is plus or minus 3%;
(i) external non-stressed panels, eg, mudguards, bonnet, bootlid and tailgates may be replaced by panels of free construction. The tailgate may be removed. It is permitted to remove material from the engine cover to facilitate the fitment of larger air cleaners, provided always that the shape of the panel is clearly identifiable. This freedom does not allow the addition of any material to the panel;
(j) two independent methods of retaining the bonnet are required eg, bonnet pins or straps, together with the original fixing;
(k) all interior trim, including the dashboard, is free.
(l) roof vents may be fitted, but they must be in the forward one-third of the roof, with their opens side facing forward, and their vertical opening not greater than 10cm.
(ii) Complete wheels (see Definitions, “General Requirements for Cars and Drivers”) must be covered by mudguards, or flares firmly attached to the mudguard, for at least one third of the circumference of the wheel (over the full width of the assembly).
(iii) Windscreens may be either removed, or replaced with one of the following:
(a) aero type windscreen of perspex, Lexan, polycarbonate etc;
(b) shatterproof, zone toughened, or laminated glass screen.
(iv) The front doors are required to comply with the following:
(a) the original front door frames are required to be retained, except that the portion of the door above the lower level of the window aperture may be removed;
(b) the door frame is required to be unchanged in the areas not covered by the original door trim;
(c) the removal of all window regulator mechanisms is permitted;
(d) the original front door hinges and catches are required to be retained;
(e) any internal anti-theft locks are required to be rendered inoperative;
(f) the door trim, if removed, is required to be replaced by flush-fitting rigid material, and
(g) if the door is modified from the original, other than as provided for in sub-regulation (f) above, door bars are required to be incorporated into the roll over protection. (See article 3.2.5.2 of Schedule J – “General Requirements for Cars and Drivers”.)
(v) The use of chassis/cab vehicles without rear bodywork, and of tray-top vehicles, is prohibited on the grounds of safety.

[Pedro_The_Swift]

SR 3 F Four-Wheel Drive (4WD)
SR 3.1 PRODUCTION 4WD
Production 4WD with engine not exceeding 6000cc for petrol engines or 7200cc for diesel engines.
SR 3.1.1 PREAMBLE
All modifications are forbidden unless expressly authorised by these Specific Regulations (SR) and where appropriate, the General Regulations (GR).
Wher
e a regulation is marked (H) the onus is on the competitor to provide supporting information from the relevant brochure or official documents issued by the vehicle manufacturer/importer/distributor.
SR 3.1.2 ELIGIBILITY/DEFINITION
A four-wheel drive automobile as defined in GR 1, of a series production type of which not fewer than 25 identical units (with regard to engine/chassis) have been marketed in Australia, or recognised by FIA and which complies with GR 2-8, 11-21, 25-29 and, if required by regulations for a specific event, GR 30-36.
SR 3.1.3 COACHWORK
Coachwork beneath the bumper bar mounts may be removed or modified.
Bumper bars may be r
eplaced with a bull bar/brushguard.
Detachable hardtops and/or tailgates may be removed or replaced.
The addition of separ
ate flares or wheel arch extensions to the original mudguards is permitted.
V
ehicles first registered for competition in Class 7 prior to 1 January 1987 and which have been modified in the area of the wheel arches may be submitted to CAMS for dispensation.
All additiona
l accessories inside the habitacle are authorised without restriction, such as those concerning the aesthetics or the inside comfort, eg, lighting, heater, radio etc, as well as those enabling easier or safer driving of the car, eg, screen washers, mirrors etc, provided that they do not affect, even indirectly, the mechanical performance of the engine, steering, transmission, road holding or braking.
R
oof vents may be fitted, but they must be in the forward one-third of the roof, with their opens side facing forward, and their vertical opening not greater than 10cm.
The use of chassis/
cab vehicles without rear bodywork, and of tray-top vehicles, is prohibited on the grounds of safety.

[long stroke]

personly i would stick a defender body on a 100'' rangie/disco chassis, i think a 110 might be a little long for tight races, although i'm not sure what the go is in terms of wheel base when it comes to off-road race cars.
I just like the look of the 100'' defenders

TIM.

[Treads]

kind of pointless getting a 4wd LR to race in a 2wd class...all that extra weight of Tcase and front difff etc etc etc etc to sort out without using it....

if racing in a 4wd class:
Id use the 110 cab chassis. Its wheel base will help with speed. Id redo the front and rear links. Using the same types but redone to suit speed. shocks will play a big roll....$$$ will get you there. Motor I would push back as far as possible. keep pushing all weight back if possible. get rid of tray and custom tube rear end, incorp a cage.....widen wheel track...TT's run about a 1.6-1 ratio of wheelbase to wheel track....If you have more $$$$ look at wildcat engines (rover based)

I had the idea of doing 2wd class for the fact that there are more mods allowed. The guy I'm pit crewing for at Warialda this year is running a 2wd converted Lada. It's much easier to run in class 5 due to less restrictions

I'd like the finished product to look something like this:


from here: Barker Land Rover Racing

The biggest challenge is finding a written off vehicle in the right condition to start with....

[Chucaro]

Have a look THIS page

for sure you are going to get some inspiration there

[lardy]

spend 50.000 gbp and by a bowler

[Treads]

personly i would stick a defender body on a 100'' rangie/disco chassis, i think a 110 might be a little long for tight races, although i'm not sure what the go is in terms of wheel base when it comes to off-road race cars.
I just like the look of the 100'' defenders

TIM.

Hmmm, sounds like an option I reckon I'd probably get away with it in Performance class 2wd too

So a defender cab on a disco/rangie chassis and probably a 109" ute tub grafted on the back?

Just thinking out loud here

Front axle
Remove front propshaft, diff centre, axles and leave standard swivel hubs etc.
Upgrade to 130 heavy duty 2" or 3" springs + secondary shocks?

Rear axle
Detroit locker, replace with welded salsibury or just weld the rover diff?
Upgrade axles to HD units?
Upgrade to 130 heavy duty 2" or 3" springs + secondary shocks?

Drivetrain
I suppose I need to work out what model V8 would be best: I'm guessing a pre 86? carby 3.5 with ?? manual gearbox would be the simplest?

Best way of making it into a 2wd and removing the transfer case levers?

Engine bay
Defender Single cab unit
All inner panels removed
Strip engine of all unnecessary ancillaries
Outer panels (guards, bonnet & grille) stripped & attached together as one vertically removable unit?
Brakes?
Clutch?

Cab
Defender Single cab unit
Everything stripped out including all glass - I like the way the firewall is when stripped out

CAMS approved cage design

Back wall of cab removed for extra race seat length and rollcage?

Ute back
109" ute back?
Tub stripped down to bare esentials


I'm trying to visualise the finished shape as being something like this?



So who wants to correct the mistakes in my thinking?