By Xmas 1999 the everyday use and sunlight was starting to make the gelcoat go chalky. Apparently Burgundy is by far the worst colour for this (NOW I find out !).
A good opportunity repair all the various holes that had appeared in the GRP though due to changing to Dellorto sidedraught cabs from the original Webber down draught. Sanding an entire (albeit small) car with 280 grade wet and dry by hand takes ages.... A random orbit sander was tried but was too harsh on the compound curves. Fortunately the local paint shop is only 2 miles away down some back lanes - I'm not sure what the local constabulary would have said !
With the 40mm Dellas fitted and jetted the problem is minus 15mm clearance on the front airfilter and top chassis rail. Burton performance parts stock a decent aluminum rocker (cam) cover that, unlike Ford's pressed steel item doesnt leak ! And it thends to deaden the valve gear noise...
After a while the foam element started to split due to contact with the bonnet. Burton again helped solve this with a 30mm deep inlet manifold - it is essentially a block of aluminum with appropriate holes drilled in it ! (much tidier than the 76mm one). Just for the heck of it I also invested in a set of competition leads. The exhaust wrap was added more to keep the engine bay cooler rather than to improve gas flow, perhaps it does help power, who knows !
The only way to get carbs right is on a rolling road. I spent an entertaining day at ??? near Shrewsbury finishing up with:
- 34mm chokes
- 142 main jets
- 7772.5 emulsion tubes
- 190 air correctors
- 55 idle jets
- 7850.1 idle jet emulsion tube
- 40 acclerator pump jet
- 7848.1 aux venturi
This gives a very tractable engine pulling hard from 2500-6200 rpm. Power curve is rice and smooth as the dyno print shows. Final power figures were 146bhp at the flywheel or 129 at the wheels at about 5500rpm. Pretty close to Vulcan's expected 150 given that the 150bhp is quoted for 45mm carbs. Given that carburation is simply the art of providing as much correctly mixed fuel as the engine needs and 40's can flow enough air for 6000rpm I didnt see the point in using 45's for a road car. In practice 5000 rpm is pretty much all I ever use. - low rpm economy/torque is probably better... most of the time.