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One aspect of the build that I have not been looking forward to was the purchase of a set of wheel rims and tyres for the car. Reason being that Lotus fitted Wobbly Web wheels to their single seater and sports racer cars. The 23 came standard from Lotus with Wobbly Webs. Wobbly Web wheels are available as new reproductions from companies in the USA and the UK. On average the rims work out at $1,000 each. A set of four with tyres will seriously drain the pocket!
As the front hubs are Triumph Herald any aftermarket 13" wheel can be made to fit. The rear hubs are made to suit a six stud pattern on a 3.5" PCD. Aftermarket wheels could be used of the hubs were modified to a suitable 4 stud layout. All certainly possible but the car would never look right.
Enter the new Tarmac magazine. In the June/July 2002 issue there is an interesting article written by John Holmes about the rebuilding of his Lotus 18 Formula Junior. In the article he mentioned that the car initially ran 13" wobbly webs but now he has fitted a set of 15" period correct Wobbly Webs. At the end of the article was Johns’ email address. Two emails later a deal was done and a cheque was in the post.
$300 for a wheel and tyre. I was very happy to send a cheque for the full set. Club member Brian King traveling down for the car show saved a small fortune in freight.
The wheels are in far better condition than what I expected. The tyres are 4.5 and 5.5 period Dunlop racing tyres. The rims are 5.5" wide at the front and 6.5" wide at the rear. The are also Magnesium which makes me wonder if they are genuine Lotus Wobbly Web rims - not that it really matters. To check offsets the wheels were compared against Dave Frows Leitch supplied rims. The rear rims have a similar offset (and they did look good bolted to his car). The front rims had a different offset which spaced the wheels further away from the car centre. The difference was soon measured - fortunately it was a “metal off” correction. To get the correct offset all I had to do was remove the tyres from the front rims. The rims were then clamped to the mill table and a the correct depth machined from the back of the rims mounting boss. It was at the stage that I was able to confirm that the wheels are infact magnesium. 
For the record the front rims weighs in at 3.5kg bare. The one minor draw back to the front wheels is that they are a 6 bolt patern not a 4 bolt as used in the originals. I have gotten around this by machining up a set of aluminium front hubs. They have been made to suit a 3.5" 6 bolt PCD. I then modified the brake disc to a 6 bolt mounting patern. The completed hubs finished up very well, and incase you’re wondering the aluminium used wasn’t a general grade. It was a very high tensile strength tooling grade which has a tensile strength comparable to mild steel. The front hubs came out at about half the weight of the Triumph hubs - all good stuff.
The front wheels and hubs are now on the car. The rear wheels are assembled to the rear hubs which are loosely mounted to the car. To finish off the rear completely the rear suspension needs to be fully assembled which means buying more spherical rod ends. To get the car to a rolling stage springs will need to be purchased and fitted, I’ll also need to modify and fit the steering rack.
As well as working on the wheels I have also been trying to tidy up and finish of some of the uncompleted jobs that crop up. The adapter between the engine and transmission is now finally completed as it has all the mounts and details machined in for the starter motor. I have also been busy machining up and fitting cam caps to the second Twin Cam head that was purchased a few months ago. This turned out to be a bigger job than first anticipated. The twin cam head had a full set of non OE cam caps but they were in an unmachined state. Milling them square and drilling/reaming the mounting and alignment holes took far longer than what I had imagined. Unfortunately not being OE when fitting up the first cap it was discovered that insufficent thread was going to extend beyond the cap to get a nylock nut to engage successfully. Add yet more machining steps as I didn’t want to machine the surface down with a end mill as the resulting sharp corner could be a stress raisor. A ballnosed cutter was used as well to get a nice radiused corner - yet more time.
Hopefully in the next month I maybe able to push the car out from the garage on its new wheeels and take a photo for the magazine.
by Martin Lucas
or a wheely good deal !!
