Hi Chaps
Thanks for the kind words, to answer a few questions:
Colin - yes no constraints or VSCC rules & the entire thing is the creation of our imagination, we've tried to be true to what the 750 Bulletins and the competition handbook guys did in the '50's and granted the MIG welder makes it easy to fabricate the tube frame, but an arc welder would have done the job and any chap with a half decent set of tools and a willingness to try his hand at aluminium could have fabricated the same in period. The LM Williams Coupe and Slippery Anne are 2 prime examples - we searched the internet for pictures and both Dad & I really like the Kaye Petre replica, so ours was modelled on that - see the pictures below, plus two of the Works racer with the long tail, this was the ones we both liked the most. I originally liked the idea of a flap down door in the side like some of the Works cars, but for me the tail on that one was too short, we like the proportions of the Petre car and the blue Works car below, so some scaling was done off the few pictures we could find based on the known size of a 19" wheel and I started bending and welding tubing.
Babbited bearings on the Green car - Steven is busy with the designs for a jig to facilitate the pouring of the babbit.
Stuart - Anti-Ackerman, having spent quite a few years in the motor industry, I fully understand what you are saying, yes I will heat & bend the steering arms and lengthen the tie rod - many thanks for this detailed observation
John - Measurements for offset: I basically shifted the diff to the side and worked out where the ideal placement for the torque tube would be & then measured the difference in measurement to where the flanges were now versus where they were when the diff was centred. it was basically bang on 200mm. The works cars had an 80* torque tube fitment, so their offset diff was outside the body against the rear hub, but modified standard diffs at 90*'s need a bit of tube between the diff & the rear hub.
Motor offset - this was achieved by balancing an empty crankcase & gearbox casing on some home made feet and working out what would give me the maximum pedal space for my feet without impacting on the angles the propshaft universals would have to work at. In the attached picture you can see the mocking up of the offset in the pictures, it seems a lifetime ago that I was shuffling the motor around to determine the ideal placement for our purposes, but in reality its 13 months, 8 of which I didn't touch the car, so 5 months of weekends and holidays from conception to now --> 80% complete and 80% still to go..... I ran a tube through the crankcase here to see where the driveshaft would end up. Once I had these measurements sorted, I then worked out the heights for the new engine mounts based on what would be needed to clear the lip at the base of the crank case over the chassis rails. From there is was simple to make and weld in the new mounting points. Once the mounts were in, I filed a shallow curve into the lip at the base of the chassis top hat section to increase clearance for the front right corner of the oil pan and ditto the left rear corner of the pan & crank case - this corner has the lump for the oil pump. Remember that I had already reinforced the underside of the chassis rails with 2 lengths of 38x38mm square tubing securely welded into place.The other mod I had to make was a shallow curve in the front cross member to clear the underside of the gearbox - I made a few horizontal cuts with an angle grinder to form a shallow C, then tapped the top lip down and just welded the everything together again.
This car actually represents a rather radical departure from the norm as we usually restore back to original, so this has been a chance to really experiment with all possibilities and virtually no constraints. We really are like kids who got a giant Meccano set for Christmas. The offset idea was purely a decision to get a bit lower to be more aerodynamic, right now we are about 100mm lower than the Green car at the chassis and over 200mm lower at the top of the bonnet. The hump at the tail is at my helmet height, so hopefully we're as aero as we can go and still look good.
The best part is that the majority of the bits were gathered by Dad before I was born and have been in various boxes in various garages for over 50 years now, so we don't feel bad modifying things as at least another Seven will arise out of the ashes, besides it's really fun
Cheers
Greig
