Big Seven Special ?

[haasad]

What's the big seven like as a basis for a special. They seem like better value for a car build not worried about VSCC certs or anything?

[Stuart Giles]

Depends on what you want to do with it really. Wheelbase is 7' 3" vs 6' 3" Short WB or 6' 9" long WB. Better brakes (full Girling) than all but the last of the Sevens. Stronger front axle with 5/8" kingpins Vs. the Seven's 1/2" version. Stronger rear axle than all but the very last of the Sevens. Big Seven motor is cast iron with a unitary Cast Iron block/crankcase and a really long stroke for its 900cc capacity. All this (mostly) good stuff means that the running chassis is a fair bit heavier than the Seven proper. At least a couple of Big Seven based specials have been built using the BMC "A" series motor which is a more comfortable fit in the wider Big Seven chassis than it is in the early cars. Google the Chris Gould Austin Epsom for an example of what can be done.

[Malcolm Parker]

The first special I built 572 BVY was a Big 7 chassis with an OHV Reliant 700cc engine.  On 15" wheels it went very well, it would spin the rear wheels in third gear on a wet road.  Speeds in the gears were approx. 20, 40, 60 and 80mph, quite fast enough.  The Girling brakes were very good indeed.
I started with a restored chassis from Chris Dalby at Kirby Wiske, I would not want to butcher a restorable car.

[dickie65]

I have always though a Big Seven chassis would make a great trials special fo MCC type Classic Trials.

[haasad]

I'm not a fan of the Chris Gould car look but they do look well built. I'm going to create a much more race inspired body, the swb, high chassis? seems the most "acceptable" starting point big they command a premium. I've been offer a LWB low chassis with front and rear axles wheels motor and g box ...no V5 for around £1k trouble is I'm struggling to see the value in it with no indication of condition of the parts which could all be fit only for the bin. I do need to ask some more questions about that one. But the big seven is cheaper as a start point as far as I can ascertain. I even looked to Morris 8s but that's quite a closed shop...

[Bill Sheehan]

There have been at leasttwo quite succesful Big Seven racing specials competing in Historic events here in Oz over the years.  I had a Big Seven special taking part in Trials in the Sixties.  It wasn't very successful - not because of the car but due to my inexperience and ineptitude and the fact it was very heavy.  To the point people got sick of roping me out of bogs, so I retired in sympathy to them.   Cheers,  Bill in Oz.

[Howard Wright]

Hi Haasad 

Before you dive in and buy a chassis you need to do some research on costs of building a special.  The chassis is at the end of the day a relatively small part of the overall cost.

I wouldn’t bank on any rolling chassis being in perfect condition and will need a fair bit of restoration then budget for a complete engine rebuild before thinking about bodywork.  I have built two specials in the last ten years and neither cost less than £6000.  In fact the Brookfields is pushing £8k.

The advantage of an A7 over a big seven is the availability of parts as there were a lot more of them made and still on the road.

Whatever you choose good luck

Cheers 

Howard

[Mike Costigan]

You could always build a copy of the Big Seven Le Mans:

https://www.austinsevenfriends.co.uk/for...s#pid40262

[haasad]

All good insight. I'm not phased by the overall time and cost. I'm so lucky to be a time served fitter with my own mill , lathe welding facilities etc. I just want to make sure I start with the best I can. To be honest the motor and box will likely not end up being A7 sourced but if I need to register it they are key to the process if they are original when inspected I think.
I will get there ...

[Stuart Giles]

To be honest the motor and box will likely not end up being A7 sourced but if I need to register it they are key to the process if they are original when inspected I think.
I will get there ...

Depending on what paperwork you have (or haven't) got, you won't necessarily have to have the original motor and gearbox fitted when you register it. All modified cars are subject to the DVLA points system. https://www.gov.uk/vehicle-registration/radically-altered-vehicles You have to have 8 points to keep the original registration/vehicle identity. A change of engine and 'box will leave you with 10 points. If you have a V5C, you will need to change the body type on the paperwork from saloon to whatever coachwork you decide on.

This subject has been discussed on here fairly regularly; this thread would probably be worth reading. https://www.austinsevenfriends.co.uk/forum/showthread.php?tid=5054&highlight=DVLA