Hi - new member, maybe, Diesel truck.

[NoThrottle]

G'day, I'm hoping to give my vehicle a run one year to see how it goes, assuming I can slot it in somewhere within the rules.
It's an offroad long course race car, but the main segments of my rollcage are oversize and should fit within your rules.
I made 197kph wheel speed and 164kph speed over ground on a loose gravel road with 240hp, so I'm thinking I could get a decent rate of knots out of it on a hard surface. The new motor has substantially more power and I have some taller diffs for it to try to reduce the wheelspin.

In the progress of my rebuild of the car I'm trying to make it fit within your safety specs, there are a few things which I'm not sure about after reading your rulebook.

Is there some rule of thumb on drag coefficient Vs horsepower for max speed? It would be helpful to determine what gearing I should shoot for. Also how much wheelspin is typical in high gears? I have no idea about how salt behaves.

Will my vehicle be eligible for the pickup truck class with no windows in it and no bottom in the tray on the back? (it's a couple of fibreglass sides with nothing behind)

The cab is steel, the engine has been moved on the chassis and so has the cab. The engine is partially set back into the cab but the bell housing is steel. Is any additional protection required to keep the driver and the formerly rotating components separated?

Will I need special tyres with a high speed rating? we regularly run tyres well above their speed rating but you might be different. Are there restrictions on tread patterns? I'd hate to trench up your salt with mudders.

Will water/methanol injection on a diesel engine put me outside the diesel class?

Does anyone know how that biodiesel motorbike is coming along?

Hopefully another couple of read-throughs of the rules with answer these questions. Also if you think I'm missing something important (apart from the windscreen) please chime in.

[RGV]

Welcome aboard. Im no expert on this kinda stuff but might be able to answer a cpl. of your questions. I think you need a fire wall between you and your engine. The bio-diesel bike is no more I think. Funding problems? Tyres must be speed rated to the class you intend on running ins record. Tread pattern dosnt seem to matter much, some very quick cars run slicks. Wheel spin can be up to 10%, depending on aerodynamics and weight. Im sure some one will come along shortly and answer the rest of your questions and correct mine if wrong.

Dave

[JonB]

Hi, welcome.

Most of your questions re compliance will be answered by downloading the rulebook and having a read.
http://www.dlra.org.au/rulebook.htm

The biodiesel bike was going to run at Lake Gairdner this year, it ran at a military airstrip in Victoria but the runway was a bit short for the speed they were chasing.

Do you have any pics so people can get more of an idea of what your talking about and give more relevant feedback/advice.

Cheers
jon

[RGV]

There were 2 biodiesel bikes? The one from Adelaide uni was scrapped I think. They did a couple of runs at Tailem Bend. 70 odd MPH. I think.

Dave

[JonB]

Same bike

[momec3]

Hi No Throttle and welcome
I have been appointed head of the class compliance board specifically in Ute and Pick up class so as you progress I am happy to help work through the rules with you.
The general safety rules cover all the classes dependent on speed.

The class rules then vary. I will need to reread diesel Pickup before I make firm comment but for a production based class the outward shape and relationship of panels must remain as std.
You say the cab and engine are set back.
The cab setback will change your class straight up. Where to, we need more detail

Engine setback you are generally allowed 2% of the wheelbase then you change class.

The floor of the pickup bed is a grey area that will require more thought also. I think no floor will be OK but this is a minor issue compared to your cab.
Post some pics and we should be able to help more.
What is it?
Chris

[DLRA 112]

I would have some concern about the Mud tyre on the salt surface.

[NoThrottle]

Firstly thanks everyone, I was expecting about 6 views by now, not 6 replies.

the engine setback is too much, it's 320mm backward of the standard position which is stretching that 2% a little bit. The cab is 100mm back on the chassis, the cab is stretched by 280mm the centre portion of the floor has been moved back 220mm so the transmission tunnel matches the gearbox.

The vehicle is primarily for desert racing and if I can do a speed run in it then that would be a bonus. I'd be fine with making small changes to fit but nothing drastic that might cripple it for my main use of it. For example the radiator in the back of the cab is the heat exchanger for the water:air intercooler, I could replace that with an icewater tank and allow the air to flow through. Also a turbo change for something that's a bit more efficient in the top end in exchange for some more lag.

The engine is sealed off from the occupants area, with a steel firewall. The doors will be a fibreglass skin only to save weight, but occupants arms are retained within the car by window nets. The B pillar visible in the photos will likely be removed because it obstructs vision too much.
Appropriate speed rated tyres means a more sensible tread pattern anyway. 10% wheelpsin is great, it was a handful at 100mph on a gravel road with 15% but some suspension geometry changes will help that a bit.

Some photos here: https://www.facebook.com/media/set/?set ... 091&type=3
and some more in my photobucket:
http://s279.photobucket.com/albums/kk14 ... ?start=all

heres some video of me driving the old version badly in it's natural environment. http://www.youtube.com/watch?v=xnxLFqZTRUM
subtract a hell of a lot of weight and add another 100hp at the wheels from there.

Sorry for all the noob questions. I'm gauging feasibility here because I think it will do allright for a diesel with some tall diffs and tyres.

edit: oh yeah its an early 1990s Nissan Patrol. not the most aerodynamic.

[momec3]

Well the cab set back takes it out of any of the production classes.In saying that we run ex Nascars in I believe Altered which technically is incorrect as their bodies are a made up thing that vaugely look like a car.

Its not going to fit in any of the Pick up or Ute classes.
You can always consider running for speed only, this just requires you complying with all the safety requirements.

Chris

[NoThrottle]

So that would be U/DT? With 156mph to beat which means gearing for 170mph. That's substantial...

My brakes barely clear a 16 inch rim. Looking at the available* tyres that fit a 16 inch or larger rim diameter with a 170mph speed rating presents some gearing problems, a 28 inch tyre height is as big as they go where I was hoping for 35 or 37 inches. The tallest final drive I can get is 3.56:1 and a 0.75:1 5th gear. That's just not enough when peak horsepower is around 3500 RPM.

I'm going to have to park this until I get time to dismantle a transfer case, replacing the low range 4wd gears with a set of overdrive gears might be feasible.

(Available* = they are in the catalogue, being able to actually obtain some is a different ball game)

Oh wow, talk about bringing a knife to a gun fight... I had no idea so much power was required.
http://www.dlra.org.au/profiles/414.htm

[BOB ELLIS]

Hey there NoThrottle,Welome along.

(Kinda funny name when you gunna need all the throttle you get),

You will fit into Unlimited Diesel Truck,-/UDT,With the tyres,if you can provide proof (written certification from the manufacturer) of the tyre load and speed rating,(Note NO square edge tyres,or any tread pattern that may damage the course),you will be OK to run those tyres.BUT (always a but),you will be limited to the speed rating of said tyres.

All the safety requirements of the DLRA must be met. Please have a good read of the rules (and read them again and again,there is a lot to take in),our safety standards are high for many good reasons.

The roll cage must protect the driver from all angles(front ,back, sides,above and below),side intrusion protection including window net,helmet restraints (SFI 38.1) are now required along with lateral helmet movement restraints (2"max side to side) , on board fire system required,blah blah etc etc.

You already have a race truck,so making some changes to run with us should not be too much problem,so keep reading,email me any other queries you may have at cambridgemotorsport@bigpond.com ,and i'll help you along,

Cheers ,
Bob Ellis,
Chief inspector,

[NoThrottle]

Thanks Bob, NoThrottle because there is no throttle. Remember diesels run on the lean side of stoich and breathe all the air they can get and vary the fuel to "throttle" the engine. It's a pretty dumb name but the sponsors didn't like the connotations of Dirty Stinkin Diesel which is what all the offroaders tend to call it.

Looks like a set of whatever 16 inch drag tyres I can find are going to be the only option, whatever tyre height that is will be it.

Here you can see the water:air intercooler integrated with the inlet manifold (if it was on a petrol it would be "rated" for 900HP it contains 6 Laminova heat exchanger cores, its performance is astounding, it cools 43psi of boost down to 35 degrees above ambient) . that oil cooler is just sitting on top to check bonnet clearance, I will probably put it in front of the radiator. I need all the radiator area I can get with this thing running close to triple the factory horsepower with no fuel vaporisation to help cool things down. You may notice the turbine housing is on backwards this is for better exhaust flow and to draw air from inside the cab where the air is cleanest because we race in thick dust most of the time, at full RPM and boost it will suck about 1200CFM.


Inside the cab, you can see the engine setback here, the gaps will all be covered in with mostly welded steel with a few aluminium inspection plates. the clutch master cylinder has to be reversed into the cab because the inlet manifold is in the way.


How much the cab is stretched:


Cab is a separate safety cell to the chassis, connected with flexible mounts. The main roll bar and front legs are 44mm CDW the other bits and all the bracing are 38mm CDW


Protection from underneath? this is the drivers seat mounting. I'll need to build a frame around my feet as well I guess, With the head restraint a HANS device is what youre talking about right? or is the lateral protection something additional?

[momec3]

Talk to Bob about cage tabs, firewall sealing, seat must be metal etc.
Basic cage design looks reasonable. Remember the chassis is not classified as part of the cage so think about support under the seat. I can't work out if you have done this already.
Talk to Bob about accepted tyres before you buy them. Some drag tyres you can use and some you can't.

Review the rulebook about explosion proof flywheel, balancer, scattersheild. There are a lot of specifics that you may need to address but its obvious you don't mind "having a go" so go for it.
Looks too me you would be in the 170mph to 200mph range. Is this about where you are aiming? (275kph to 324kph)

Bit hard comparing Clydesdales to Thoughbreds.
Your mates are right Dirty Stinkin diesel.
I paid diesels no mind till they won at Le Mans, then did it again and again.

Chris

[outbacktrev]

Welcome on board "no throtle". Remember ALL, how your tucker and more importantly your beer gets dragged around this country and up to the lake in a lot of cases (no pun intended ) by a "dirty stinkin diesel"
Cheers,
Trevor

[NoThrottle]

Looks too me you would be in the 170mph to 200mph range. Is this about where you are aiming? (275kph to 324kph)

I really haven't got the faintest idea what speed to aim for. What makes you think it could go that fast?

These cars have the aerodynamics of a 1980s volvo and it would sit about a foot higher than most other things on your track,
also the engine performance is strange, we make peak torque of 700-750 ft lb at only 2500 rpm and peak horsepower at around 4000 rpm, it's balanced for 6000 so we can wind out top gear but diesel doesn't burn real fast so power is down and EGT is up there with lots of RPM. There will be a wind resistance=horsepower brick wall I expect. or a wind resistance:traction brick wall.

Still haven't gotten around to another read, Will print it out and colour in relevant with a highlighter until it makes sense or turns yellow.
it's certainly an interesting thing to consider.