Thank you all for your quick response. I have passed it on. If he can overcome
these hurdles, New Zeland will have an amazing looking car n its roads. I can’t
say much more about it at this stage as it is a possible future NZ production
kit car. Currently, he aims to launch it at the Big Boy's Toys Motorshow in
2021.
Cheers
Patrick
From: ccc-qna-bounce@xxxxxxxxxxxxx <ccc-qna-bounce@xxxxxxxxxxxxx> On Behalf Of
Mark Errington
Sent: Tuesday, 23 June 2020 8:10 PM
To: ccc-qna@xxxxxxxxxxxxx
Subject: [ccc-qna] Re: Roll cage stiffening of a kit car.
Hi Pat,
The roll bar on my Factory Five kit was of cosmetic value only. It was
optimised for a show car.
Who is going to make the cage – you can probably not make it yourself! For a
car road registered under a Motorsport NZ authority card, the cage has to be to
a recognised design (derivatives of FIA Appendix J) and fabricated by an
accredited fabricator. When I presented this problem for a space framed car to
my accredited fabricator, he knew what to do. My recommendation would be to
put yourself in the hands of an accredited fabricator and discuss the options.
Then follow their advice. We were able to do this in consultation with the
certifier.
Cheers,
Mark
Akaroa 021 334 612
From: ccc-qna-bounce@xxxxxxxxxxxxx<mailto:ccc-qna-bounce@xxxxxxxxxxxxx>
<ccc-qna-bounce@xxxxxxxxxxxxx<mailto:ccc-qna-bounce@xxxxxxxxxxxxx>> On Behalf
Of Brian Worboys
Sent: Tuesday, 23 June 2020 7:44 p.m.
To: ccc-qna@xxxxxxxxxxxxx<mailto:ccc-qna@xxxxxxxxxxxxx>
Subject: [ccc-qna] Re: Roll cage stiffening of a kit car.
Hi Pat .. for your friend .. some thoughts from me..
1. If they are taking strength out of a chassis and replacing it with a roll
cage, or any other structural components, and planning for the car to be road
registered, then it will be up to their certifier as to what is adequate. The
MSNZ standards won't necessarily have any bearing on it. The MSNZ cage is not
intended for that function. It is to protect the driver when the car crashes.
2. To get the roll cage certified for motorsport there is more than one route
to take. One is to have the installation analysed by a recognised structural
engineer as meeting the required loading criteria. The easier and cheaper
route is to use the standard designs in the manual. These have specified tube
layout, tube specifications and footing sizes. The footings are 120 cm-squared
and 60 cm-squared. Approximately two hand prints and one hand print.
Considering that the footings are distributing several times the car's weight
into a panel steel structure, I think the size is not unreasonable. It is
certainly easier to just use this than try to find an alternative way to cage a
car for motorsport in NZ.
3. The MSNZ cage can contribute to overall chassis strength and stiffness but
it can't be used to accept suspension loads directly. There are a few (possibly
not clear in the manual) limitations on what can be attached to the cage.
Pat, I'm not sure if I've understood your friend's situation correctly. Happy
to have a go at any follow-up questions. Cheers, Brian
==========================================
On Tue, 23 Jun 2020 at 17:51, Patrick Harlow
<patrick.harlow@xxxxxxxx<mailto:patrick.harlow@xxxxxxxx>> wrote:
Greetings
A friend of mine is building a kit car similar to Ross Baker’s Heron Alana. He
is using the full floor pan/firewall and drivetrain off a donor vehicle.
Because he has cut the roof off the donor car, the kit comes with a roll cage
to stiffen the chassis back up. As it is an overseas kit, the roll cage will
have to be modified to meet New Zealand standards. He is finding the New
Zealand standards quite confusing especially the plate size required to fit the
roll cage to his floor pan. See below….
Hi Patrick.
I wanted to get your opinion on information from the Motorsport website.
As you know I am reading up on all the info on roll cages.
Schedule A, Appendix Two, Part Two, Article 5, 5.5 1 (a) For the main and
lateral rollbars a reinforcement plate with a minimum area of 120cm in full
contact with the surface of the bodyshell shall be used.
120cm? That's big!
(b) For all other members a reinforcement plate with a minimum of 60cm shall be
used.
60cm? This is also big!
Let me know your thoughts?
Cheers
Patrick Harlow
