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MG MGB GT V8 Factory Originals Technical - Firewall Mods

Hi Folks,

I have completed all the rear end mods on my conversion and about to start on the front. I am using Roger Williams book "How to Give your MGB V8 Power" which has been good so far.

What I need to know is, are there any problems that any of you have had when modifying the firewall using his instructions?

I don't want to follow them blindly, to find out that they weren't ideal. I would appreciate some of your experiences.



I followed the book exactly in that regard. My car is a 1964 roadster and all the measurements worked out well for me. I was fortunate enough to have a factory V8 gearbox which made things simpler.

I was also fortunate enough to buy very cheaply a damaged rubber nose body shell, from which is cut all the shapes I needed.

The book is the best starting point for anyone converting a CB car.


Ian Buckley
Ian G Buckley

Stainzy! Glad to hear it! You won't regret it a bit.
One thing I did that worked out well: On the right side corner rather than patching in a small piece as I did to start with, if you look below that corner you will notice a curved vertical section which forms a part of the end of the footwell. Using heavy sheet metal I simply continued that curve all the way up to the shelf, bending the lip of the shelf over it the same way the rest of it is. You don't lose anything behind the dash that you would use, and it makes access in that area easier, and best of all makes a nice clean job of it. Not sure what Williams recommends, but that's the way I would do it.
Jim Blackwood

Thanks guys,

Will continue to use the book for the most part. Jim you gave me an idea that I'll use on the lip of the shelf to keep it looking as consistent as lips/curves/joins etc.

Not sure what you mean about the curved bit on the right hand side, but over here in Oz we're right hand drive so, unfortunately I don't know that I'll be able to do it given the position of the steering cone and all.

Wish me going out now to do battle now.

Thanks again,


It's the hump with the plug in the top for checking the transmission fluid on the stock B. Can't see much of a problem with extending that up to the shelf, can you?

Jim Blackwood

Thanks Jim, I know what you mean now. It sounds like a pretty good idea to me. This afternoon I cut out most of what I need to, but will take a bit more off the right hand side to do as you suggested. Let's be honest, you can never have too much room in there.

Thanks again,


This thread was discussed between 12/09/2002 and 14/09/2002

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