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Capri Engines

1) S0HC PINTO

Introduced in 1970, the Pinto engine has been produced in 1294cc, 1593cc, 1796cc and 1993cc capacities. The 1.3 was rarely used in UK models (mainly on early Sierras) since the 1.3 X/flow was used more often in its favour. Both the 1.3 and original 1.6 used the same short rods and crank However, the later 1.6 E-max (introduced in 1984) shares the same longer rods as the 1.8 and 2.0 engines.

The 2.0 engine is easily modified to any stage of tune, but using anything other than a fast road cam in the other engines can create rocker geometry problems. A typical fast road tune will include a modified cam, flowed head and the best of the standard carbs - the Weber 32/36 DGV/DGAV. As with the Crossflow engine, a whole range of parts are available to modify this engine to any stage of tune. Always check for valve to piston clearance as you never know how much has been taken off the head and block in the past. Compression is easily raised by skimming the head and can be increased up to 10.5:1 before having to consider forged pistons. These pistons can take up to 12.1:1 compression. Capacity can be increased to 2090cc by using the 2.8 V6 standard piston (93mm). To use these pistons, the small ends will need to be narrowed and the block needs to be decked. The 205 block (used in injection and 2wd Cosworth engines) will easily bore to 93mm without breaking through. The standard block will often bore to this size but cannot be guaranteed. The injection 'wide beam' con rods are a good fitment since they should take 7500 rpm using a good big end nut and bolt. The flywheel should be double doweled to the crank for HD and competition use to prevent the increased torque shearing the flywheel bolts. When aiming to produce more than 150bhp, we would only recommend using twin 45 DCOEs.

2) ESSEX V4/V6

The original Essex engines were produced in 1965 and were available in 1663cc and 1996cc V4 capacities. A year later the 2494cc and 2994cc V6 versions were introduced. In 1970 the design of these engines was 'uprated' which resulted in a stronger and more powerful unit (but unfortunately, not lighter -the V6 is a very heavy power unit). The post 1970 uprated 3000cc engine is the most popular unit for modifying and all further information relates to this engine type only. At this juncture it should be pointed out that the pre 1970 and post 1970 engine types have many components which, although similar in appearance, ARE NOT INTERCHANGEABLE. So if you are sourcing used parts, be careful. The 3 litre Essex is renown for its high torque characteristics which gave it the most grunt of all Ford UK production cars at that time. Although it has a very useable 136+bhp in standard trim, a 20% increase on this can be fairly easily achieved for fast road trim. The V6’s potential is well over 200bhp but the cost and ultimate reliability of such conversions means there is little demand for tuning to this level.

The first modification to this engine is to replace the restrictive airbox for a K&N filter. This alone will regularly see an increase of between 5-8bhp with the 38DGAS carb. The V6 responds well to a cam change and, if funds allow, a pair of modified heads. The original Group 1 conversion used a Weber 40DFI5 carb and, providing the mechanical lift pump is replaced with a higher capacity electric fuel pump, will cope with power outputs of at least 185bhp. Don't forget to modify the pistons when using a high lift cam and larger valves, as the original valve pockets will no longer provide the necessary clearance. The most common component failure on this engine is the camshaft drive gear. This should always be replaced with a new gear during a rebuild and a modified steel gear is recommended for all stages of tune. Although there is a trade off with some increase in gear noise against the standard nylon or fibre material, the risk of the standard gear stripping its teeth are very high. Another weak area is the design of the crankshaft lubrication and it is imperative that the crankshaft is cross-drilled if engine speeds in excess of 6500 rpm are to be used. The con rods should be fitted with heavy duty bolts and pay close attention to the press fit of the piston pin in the small end which can be another bone of contention with this engine. Removing any weight from the rotating components (in particular the flywheel) will seriously upset the balance of the engine. A full rebalance is therefore essential. Moving up to the top end, another weakness is the pressed steel rocker arms pivoting on a stud which is only pressed into the cylinder head. For any high power conversions the studs must be replaced with threaded ones and a stronger roller rocker kit fitted. For the really serious tuner, oversize forged pistons that increase the engine size to 3161 cc are available as well as conversions to use either a 4 barrel Holley carb or triple Weber DCNF carbs. These are just a few of the many items now available for this classic engine.

3) COLOGNE V4/V6

The V4 engine was originally designed in the USA for a new car that was cancelled before it reached production. This engine was then fitted to a number of German Ford models, but was not fitted in any Ford model produced for the UK market. It was available in capacities of 1183cc, 1288cc, 1305cc, 1498cc and 1699cc. The V6 engine was introduced later in sizes of 1812cc, 1998cc, 2293cc, 2551cc and 2792cc. The 1.8, 2.0 and 2.6 V6 engines were only fitted in German Ford models, not UK models. In 1989. Ford introduced a redesigned engine in sizes of 2394cc and 2935cc. The 2.9 engine was also used as a basis for the Cosworth 24v quad cam engine.

In the following text, we are only concerning ourselves with the two larger types of V6 engines, although tuning principles remain the same for all sizes of engine. Although slightly less in capacity than the Essex V6, these engines are lighter and more powerful (150bhp) but have less torque or grunt than the Essex. Basically, the 2.9 unit is a longer stroke version of the 2.8, but there are also other more subtle differences between these two engines, which makes any interchange of parts very difficult. The 2.8 cylinder head has a 2 port Siamese exhaust manifold design as against the more conventional (and better) 3 port design on the 2.9. Like the Essex engine, the 2.8 V6 had the same type of cam drive gear design and the same associated problems. The 2.9 has a much more reliable chain drive for the camshaft. The 2.8 engine can be tuned to a reasonable level (modified cam, staged heads, steel cam gear, etc.) but the poor cylinder head design is its ultimate restricting feature. The American version of this engine was fitted with 3 port heads but such items can be difficult to source in the UK. For those wishing to convert their 2.8s into 2.9s be warned, it is not easy and it is not cheap. Because of the different exhaust porting the camshaft phasing is different (they also rotate in opposite directions to each other). The 2.9 distributor, oil pump and drive shaft will also be required. The differences in the chain and gear drives means that, if you fit the 2.9 crank in the 2.8 engine, the front nose will require modifying. And because of the longer stroke crank, the pistons will protrude approximately 1.5mm above the deck face. The piston crowns can be machined down but this will affect their ultimate strength, especially if the compression ratio is to be raised. With the 2.8, the con rods are the weak link. HD ARP con rod bolts are essential for over 6000 rpm. A con rod that has been stress relieved and shot peened can rev safely to 6500 rpm. An electronic rev limiter is a must have to prevent the consequences of over-revving. Carburetor engines can get good performance using either the 38DGAS or 40DFI5 and, for the more serious, conversions have been seen using a 4 barrel Holley carb. The inlet manifold on the MFi K-Jetronic injection engine is a serious restriction. The four 'risers' basically do not allow for sufficient airflow. Unfortunately there is not enough wall thickness to allow these to be opened out. so the only way to solve this is to build up the outsides with welding. With the risers sufficiently opened out, we have seen instant increases of approx. 21bhp.

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