South Aus Dry Lakes

[muttis3lv6]

Has anybody done this?
what can i expect?
What additional mods would you recommend and why?

http://www.dlra.org.au/dlranews.htm

[1320ft]

Have a read of the rule book 1st.

Their rules are even more comprehensive than ours (ANDRA)

[jk]

What additional mods would you recommend and why?

I don't mind a bit of dry lake motorsport. As mentioned above the rule book will dictate any minimum mod requirements for safety.

But in general performance chasing:
- reduce weight where possible
- improve frontal aerodynamics to reduce drag and lift
- put in the tallest diff you can, with maybe a diff oil cooler?
- horizonal tail spoiler for some stability

I'd take a look at some of the eighties/ninties US racing beat rx7's for what an all out effort would take (ignoring that they put at least one car on it's roof)

[fugazi]

This is howtooooo:
Blowfish

[muttis3lv6]

Ok
My car is already pretty serious, roll cage weight reduction, upgraded suspension etc. My aim is to get into the 150 club at 250 km/h about 30 clicks faster than i have ever been (221 on my CBR600). Bloody fast i recon but should be acheaveable?

I am thinking about getting another set of doors and stripping all the mech out, running perspex windows in them also the back window. cant think of anywhere i have excess weight, except for my fat ass

I want to run the tallest tires i can on the back, any idea on what that would be with out worrying about rubbing?
What diff ratio should i be aiming for?
How important would a diff cooler be?
any other advice?

[Alspos]

I just read an article in Street Commondores (191) about a salt lake racer. In the article they are saying they have added weight to the car as opposed to removing it. My guess would be for additional stability at speed? S'pose it doesn't matter how long it takes to get to speed. If I remember I'll scan it next week and post it up.

[jk]

I want to run the tallest tires i can on the back, any idea on what that would be with out worrying about rubbing?
What diff ratio should i be aiming for?
How important would a diff cooler be?
any other advice?

To sort out your diff ratio will depend on your tyre size but you'd probably want to calculate it out to put the top of your engines power band either at or just beyond 250km/h if that's your aim.

The diff cooler idea from me is just brain storming, I have no real world experience. I'm thinking at extended very high speed driving (up to a few minutes per run) it may get pretty hot, closing up the tolerances and adding to your powertrain drag and also if that same heat/situation causes the diff to fail in a catastrophic way at high speed it could throw the car into a spin. So, as insurance more than anything. Did groupA racers use a diff cooler, do other salt racers typically use one?

Other advice?
Are there any online forums or real world car clubs who can answer these sort of questions with any certainty?
Is there a sort of Moroso calculator you can use to put in data like HP, torque, weight, gearing, drag co-efficient of the vehicle body (stock starion figures could be a guide here). Some number crunching might give you a good idea whether your target is achievable or not.
If it's a real nice road car do you actually want to take it on the salt. You'll come away with salt stuffed into every nook and cranny of your car :(
These events are also notoriously exposed to the whims of nature, You may prep all year for it, go all the way out there and the salt just isn't up to it. With other challenges of setup and mechanical break downs, it's the sort of thing that might take you a few goes to reach your aim

As for Als weight adding comment, I can see a case for the old "strip it down to minimum, then add it where you want it" senario. Like putting the weight either low in the car or front/rear to help side to side stability and with steering feel or riding the supension over any corregations/undulations in the coarse. I'm sure the runs are pretty flat but they may not be perfect.
I tended to think getting up to a high speed was the challenge, but maybe getting up to 250km/hr is easy, and the challenge is keeping it there for the full run. A little like how laymens look at drag racing and say, too easy, just hold the wheel straight and hit the gas. But when you look at in-car footage of a doorslammer the drivers fighting the wheel almost alll the way down amongst other tasks. Maybe this salt racing is the same, getting to 250 is not the problem, it's holding that speed while fighting head/tail/cross winds and any imperfections in the coarse.

[redzone]

250 is a piece of piss in a starion with a 3.5 ratio diff, what wheel diameter are you planning on running? 7000rpm rpm max? You will want it mega low and get your rear camber zero'd

[muttis3lv6]

hay redzone, what do you think the top possible speed of a staz is?

[thrash]

muttis3lv6, you good at maths? what do you do for a living?

[muttis3lv6]

I am a Civil Estimator why?
What is the formula and what are the variables?

[groupAralliart]

260 out the back of toowoomba in my Ralliart JA.

[jk]

I've been reading a little recently on eighties and nineties porsche, lotus, ferrari etc 150 to 180mph is fairly common in standard trim, so a hotted up Staz sounds fair enough.

For a trek to the salt I reckon the big 200mph is the one to set your target on, the old hotrod holy grail.

[redzone]

hay redzone, what do you think the top possible speed of a staz is?

If you employed some aero tricks I think 300kph would be possible with a 3.5 diff & 400rwhp with a decently high rev limit

[thrash]

the variables are far too many.

BUT - just as there are drag racing calcs, here's a salt lake racing calc:

http://www.rbracing-rsr.com/aerohpcalc.html

Inertia is the name of the game.

In drag racing, you are attempting to use your car's power to fight the inertia of the car standing still caused by its weight. Hence, power to weight ratio is of utmost importance.

In top/high speed runs, your car is putting all its power into fighting the inertia of the stagnant air around it, so the power used to accelerate the weight of the car is minuscule compared to the power required to force the air out of the way. If your car has a lower drag coefficient and lower frontal area, this allows it to swim through the air much easier, and less power is needed. I wouldn't be worrying about the weight of the car itself at all. Reducing your drag coefficient at the expense of extra weight will pay off in this situation.

According to autospeed, the starion as standard has a drag coefficient of 0.32 if i'm not mistaken. From memory, your car has a huge ass gt wing at the back. So the first thing you need to do is rip off this wing - but do it gently of course if you want to put it back on after the fact. Do some research on drag and how to reduce it - i reference autospeed again as they have some interesting articles on this too. lose the windshield wipers on race day. run smooth tape over all panel gaps. bolt some aluminium sheet to the underside of your car to make it completely flat - and perhaps while you're at it, mold the back of it into a diffuser. If you have a JA with a chin spoiler, lose that, it's not the best and will cause the front of your car to lift at high speed as it forces air up against the underside of your bonnet. A JD front airdam might be the go here. Make sure your wheels / tyres don't stick out the sides of the car, but don't sit too far in either. I would stay away from deep dish wheels on race day - while they look freakin awesome, they do increase turbulence in the area. Also take off your side mirrors if you can be bothered.

Oh and pump your tyres up to almost max pressure

From what I understand, salt lake events are few and far in between, so do as much research as possible to get everything right on race day. 150mph might be an easy target on bitumen, but salt lake surfaces are not sticky. While your speedo hits the 240km/h mark, the actual speed of the car may only be 200 - you have 40km/h worth of wheel spin due to the low friction surface. Keep this in mind when using the calc, as it will not be able to account for wheelspin, among other things like head or cross winds and the like - too many variables to stick into a single formula and get accurate results.

Ok, so that was a long ass rant, but I hope this helps - it is what I'd be looking at doing if I were entering such an event

DISCLAIMER - I am by no means an expert - I invite people to prove me wrong if it will assist in getting a starion to any race event :beer