Technical information

  • Rollbars

Roll bars and the Blue Book

How the regulations for rollbars as specified in the MSA Blue Book may affect you - as researched by Jack Bellinger and Andy Downes in 2007.


Our new Eligibility Scrutineer. Dallas Smith, has been a scrutineer for 50 years and knows Morgans well, he’s spoken to the MSA on our behalf and they have said that “Common sense should prevail” as far as Roll Bar issues are concerned. They understand that we are a road-going Series, that some of us drive to the circuit, that this is part of our racing history. and that Roll Cages are not legal for the road. However they are also clear that it is the scrutineers are entitled to decide as they see fit on a meeting-to-meeting basis.

The Blue Book must be adhered to.

The following comments apply particularly to Roll Bars based on the 2006 Blue Book, so if the 2007 Book differs please let us know.

For Sports Cars up to 2000 cc
Ref: Q.1.5.1(a) Basic rollbar/rollcage complying with Q1 or Q2.
For Sports Cars over 2000 cc
Ref: Q.1.5.1(c) Rollbar/rollcage complying with Q3 or Q4 or Q60(i) & (ii) and Q31.

The Roll Bar design must comply with Q60 (i).
We must comply.

Height - we can find no specification for the overall height of the Roll Bar for Sports Cars.
No issue.

The top edge of the Roll Bar must be at least 5cm above the top of the helmet of the normally seated driver – Q31.
We must comply.

The vertical centre of the Roll Bar tube behind the driver’s head must be no more than 25cm behind the back edge of the helmet of the normally seated driver – Q31.
We must comply.

No part of the driver’s helmet is to pass through a straight line from the top edge of the Roll Bar down to the ‘Substantial Structure’ forward of the driver – Q60(ii).

Simplistically we must comply.

BUT - There are differing possibilities/opinions as to what constitutes the ‘Substantial Structure’ and it may be different on different models (e.g. Flat-Rads), the MSA will not specify where it is – that’s down to the scrutineers;

The top of the cowl
The top of a hoop fitted to the cross-frame under the cowl
The top of the cross-frame
The top of the wings
The top of the tyres
The top of the engine
The top of the scuttle/bulkhead
The top of the windscreen.

It is suggested that we explicitly specify in the Technical Regs that a standard MMC cowl MUST be fitted (for strength) if we want to push strongly for the cowl to be that structure.

The Blue Book does not deal with extensions to the Roll Bar – either Small Extension Hoops bolted to the top of the Roll Bar, or Large Full-Width Hoops bolted to the uprights of the Roll Bar.

The feeling is that the Small Hoops will not comply, the MSA do not like them as they have no brace, they can ‘dig in’ in the event of a roll, the mounting holes may compromise the original Roll Bar structure.

BUT – we may have a case with the Full-Width Hoops although they have no direct brace, but the mountings are via the existing seat belt holes so the structure is less compromised.

There is nothing in the Blue Book that suggests the requirements above are any different when a Hood or Hard Top is used on a Sports Car.

We should assume that ALL the above will still apply, unless you can convince the scrutineer that the front of the roof/windscreen is ‘substantial’.

If you have a problem complying with the Roll Bar requirements then you have some pretty basic options

1 – Lower the seat
2 – Raise the Roll Bar
3 – Put a brace on the crosshead under the cowl
4 - If you’re not road legal, fit a Roll Cage

We are not the only cars with this potential problem so the scrutineers will have to be sensible.

Tech Comm