AC Engine Project
Life for The Weller 2 Litre 6 Cylinder Engine
History
In the relatively short time since the AC Engine Project first commenced, considerable progress has been made in the implementation of its objectives, which are to examine the engine and its support structure and bring both up date in terms of the reliability and performance of the engine and the generation of a wide range of spares and services at reasonable cost to the engine owner.
Since the Project was announced, interest in its progress and achievements have been considerable and much encouragement has been offered. We have also received a lot of questions, particularly regarding the blocks and these are summarised and answered below.

What technical advantages do your new blocks have over any other?

We have the great advantage of having started with a clean sheet of paper instead of slavishly perpetuating shortcomings left over from the past. Our blocks, whilst respectful of tradition, are also much enhanced technically. This will bring immense benefits to the user in terms of engine life, performance and ease of maintenance. Why pay inflated prices for yesterday's technology?

What does that mean?

It means that our blocks incorporate some refinements not available elsewhere because we are doing a lot more than simply producing replacement blocks. We have applied original thinking to our blocks and have introduced several innovative features to improve engine reliability, maintainability and where required, the ability to greatly increase engine power output without the fear of the block suffering structural failure as a consequence. We believe that we have the edge in quality, technical competence, built-in flexibility to suit different requirements and above all, cost-effectiveness.

We have also treated our new blocks, not in isolation, but as part of our re-appraisal of the whole engine. In other words, the refinements that we have made on the block have been analysed for their impact on the whole engine, and indeed, vice-versa.

My block is fairly good. Why should I buy something that I don't need?

Even if you don't need a block today, there is a high chance that you will tomorrow. Also, it makes economic sense to put one on the shelf for later, thereby future-proofing your treasured car and thus protecting its value. The saleability of your AC will also be much enhanced if sold with a new block, whether fitted or spare. It is worth noting that the single most frequently quoted reason for not buying an AC is the widespread and well-known fear of trouble with cylinder block corrosion.

I have a PVT AC and an Aceca and I would like a block for each.

The Project is unique in producing both PVT and post-war blocks. This has been of great benefit in reducing the cost to the customer, as our casting patterns are convertible for either type of block. This means that the financial investment in the patterns can be amortised over a greater number of blocks than would be the case with only one type of block, thus reducing purchase cost.

Which crankshaft can I use in your blocks?

The blocks have been configured for use with just about any AC or bespoke crankshaft, so whether you just want to potter around in the sunshine or rush around in competition, the blocks are entirely suitable. For the latter activity of course, the Project's own highly advanced crankshaft, designed especially for the blocks, will create the ultimate in strength for really high performance engines. Although new blocks and new cranks have been available on and off for several years, the Project block and crank are the only ones that have been developed together.

What are you doing with camshafts?

We have two camshaft types in stock here and now. Both have been designed exclusively for the Project by a leading UK specialist especially to suit to suit the characteristics of the AC engine. The first is a fast road cam and we expect this to be the most popular, either as a straight replacement for worn out camshafts or to bring a useful increase in performance for modern road conditions. The second camshaft is a pure sports cam designed to allow the engine, in combination with other modifications if required, to develop maximum revs and also the all-important torque required to power a car out of a bend on the track. Of course, there is no reason why the enthusiastic driver should not use this cam on the road as well.

How are your experiments going with head gaskets?
 
So far we have had some success with the tanged graphite gasket material, however these still present some failures between the liners & require further development, and we have a new concept gasket from the USA which is due for trial soon.
Until we have a satisfactory solution the only gasket one can consider with a degree of confidence is the traditional Copper Asbestos type gasket, however even these fail in the area between the liners occasionally & are also difficult to obtain a consistent water seal around the block. I believe this is due to the various thicknesses having overlapped joints which are essential to avoid water deterioration of the asbestos replacement material.
As we now have new liners with four inches between flanges instead of three & fifteen sixteenths inches more options exist for both top & lower sealing methods.
 
Work is therefore ongoing & will be reported upon as we have more results.