I've cut most of my tubes to the metric lengths stated in the book. Then (Big mistake I think), I looked at the McSorley book chassis. It's got some _big_ differences. Take, for instance, Y. It's 813mm In the book and 914 in the McSorley. That's practically 10 cm longer...

So, what I want to know is:

1) Which is "right"?
2) Which should I use?
3) Seeing as the McSorley one is different, is it still legal for the Locost Race Series?

4) (This is a sorta unrelated question) Is 1.5mm thick steel legal for the Locost Race Series? It says 16G in the regs and book, 1.5mm thick was the closest I could find.

The book is full of mistakes and I would advise you to use the Mc sorely plans throughout. I'm using them for my442 and so far everything has been pretty much spot on.
Do'nt cut everything in one go that way any mistakes on a long part can be nullified by using it for short parts.

as i am aware for the locost series the chassis has to be as per the book.

www.gmpmotorsport.co.uk

McSorley and book DESIGNS are identical, but McSorley measurements to achieve that design are correct.

The +4 is another bag of onions though