Twin Cam Rebuild.
Over the past twenty years I have accumulated a vast knowledge of the Lotus Twin Cam Engine. It was originally designed by Harry Munday in 1961. For a full history and insight into the Lotus Twin Cam Engine read Miles Wilkins book "The Lotus Twin Cam Engine" if you can find a copy!
An inline four cylinder, four stroke, twin overhead camshaft unit with a cast aluminium cylinder head which has hemispherical combustion chambers and a separate ports for each valve. Based on the Ford 1500 pre-cross flow block, it was and in many ways continues to be a revelation.
There is much rubbish spoken and written about the Twin Cam, but it is still a great little power unit and there is no reason why it can't be a reliable engine which is both reasonably oil and water tight. Although it was originally design to run on leaded fuel with the addition of hardened valve seats they will run quite happily on unleaded fuel.
By the time these engines have been used for a few of decades, with limited servicing and repairs, they get very tired and dirty, they smoke badly, start poorly and are generally very unsatisfying to use. With a little time, money and dedication they can be transformed back to their former glory or perhaps better.
The many years of grim leads to much time spent stripping and cleaning, but this gives us the opportunity to give each component an inspection for damage. One area that much has been spoke about is the water pump, providing it is overhauled by someone who knows what they are doing, using quality components and the drive belt is not over tightened there is no reason why it should not give years on trouble free service.
After the head is stripped and cleaned our machine shop fit the new unleaded seats and valve guides, they then accurately re-cut the valve seats, we then take over grinding in each valve by hand, we then reassemble the valve springs, followers and cam followers and reset the valve clearances.
At the same time the head is having it new seats fitted the block has the bores measured and re-bored as required, the crank is also measured and reground or polished if within specification .
Each external component is then degreased and painted usually in the original battle ship grey, we also have the facility to repaint the crinkle finish on the cam cover. Then the engine can be reassembled ready for re-fitment.
If you have a Lotus Twin and feel its getting a little tired why not give us a ring and discuss the options or arrange to bring it in and we can check it over, carry out a compression check and perhaps a cylinder leakage test and we can decide on the way forward. 01483 573737