Australian Chassis Test
 

Hi all!

I'm about to start building my chassis this weekend. Does anybody know if a Gibbs chassis built to book spec will pass Australian beam torsion testing?

I've seen that a few Australian builders post on here and wondered if anyone had gotten to the testing stage yet.

... I'm going to be using MX-5 rolling gear, brakes and diff powered by a 4A-GE 20v blacktop through a T50 box. Will take some pics at the weekend and start a build diary once i get some steel down.

This was covered a while ago. I dug this out of the search section.

MarkB MarkB is offline
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Join Date: May 2011
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Quote:
Originally Posted by ozzy1 View Post
Join a car building club and ask around.The club may have certain Engineers who are more clued up on the style of car and you might have to classify it as a locost to aid ther issue.Just a thought.
I 2nd this as the Locost has been through the Australian testing system although it did have to have extra tubes adding to stiffen up the chassis. Quite sure the front frame section requires one or even two tubes within it to create triangulation.

Bob

It depends on the state you live in,some are strict on it and some will pass it if you put in the extra bracing required based on the original ron champion design without testing.i will try to find my wa based manual and send you a copy of the page with the extra bracing required(not home til next fri 23rd)also if you build from 2mm wall this gives a 25% increase in weight but a 30% increase in torsional rigidity alone.

Thanks guys...

I'm in Adelaide, SA and will have to have the chassis beam and torsion tested by (or in the precence of) a chartered automotive engineer. I know there are loads of Champion derived chassis and other custom designs register in Australia but i've scoured the Aussie forum and can't find an example of a registered Gibbs chassis.

I'm going to be using 2mm for 25x25 and 1.6 for my 20x20... The area that concerns me is the 'kinks' in the front frame. I think even with the Aussie mods triangulation they may be a weak point.

Can any one tell me the purpose of the kinks in the upright sections of the front frame? Will everything else fit if I rework this with striaght box section?

Kinks on the front upright are where the front suspension mounts are. Shouldn't be too hard to make some that work with a straight piece..

Most designs have this even Westfield.Dont see it being a problem really.I think the McSorley design front frame has straight sides.Anyway here is a useful link with some info;

http://locost7.info/mirror/aussiemods.php

You could always do as I did to make it stronger and make the lower and upper rails in one piece of steel cut to the chassis shape.

May keep the inspector happy.

Really would be interesting to see where the extra bracing ends up as this would be an improvement that should be added as a matter of course. Its stuff like this that improves the breed.

bob

here are mods on locost chassis;

http://locost7.info/files/chassis/au...s/framemod.jpg