If the intention is to get more power from your engine, it is often immediately considered to increase engine capacity in conjunction with larger carburetors. If you want to double the standard power, this will be an important aspect, but for a power of 20 or 30 hp more, you don't need to take a larger displacement.
Mounting larger carburetors with a performance camshaft and a cylinder head set with larger valves can take you very far, you can build a fast engine for everyday driving in a responsible way. Read carefully here the explanation that corresponds to the selected cylinder head, so you can make an educated choice.
Autolinea 041
This is not a ready-to-use cylinder head, it is delivered empty, which may have the advantage of allowing you to choose valves, springs, etc. to be mounted. The finish of Autolinea 041 is in any case much better than that of their standard cylinder heads (which are not offered by Paruzzi). You will still have to adjust and change several other things if you want it to be perfect, such as levelling the combustion chamber, grinding the valves and eventually finishing the inlet and outlet ports. It may seem strange to have to do additional work on new cylinder heads, but this is a well-known fact at Autolinea. Even after much insistence, there is little change, the most important target group is probably the professionals who are used to making adjustments and Autolinea can thus keep the price low. Autolinea 041 is equipped with more material between the spark plug hole and the valves to avoid known cracks between the valve and the spark plug hole, so 12 mm thread spark plugs should be installed (see the options tab).
EMPI GTV-2
This cylinder head is not based on Autolinea but on a new cylinder head developed by EMPI. With the EMPI GTV-2, the space between the valve and the spark plug hole has been further reinforced and uses 12 mm spark plugs. Compared to the original, the EMPI GTV-2 is 50% more robust and has 44% more cooling surface area. The inlet and outlet ports are 20% larger than the original and there is more material that can allow for additional expansion. They are supplied complete with stainless steel valves and double valve springs with chrome-molybdenum valve springs to prevent floating valves at high speeds. However, it is necessary to mount reinforced valve stems with stainless steel valve stem caps, the caps are not included, order them in addition (see options tab). The EMPI GTV-2 is delivered ready for assembly, but do not take any risks and check the location of the valve before assembly. A professional always disassembles everything to check with his own eyes and measuring devices if the cylinder head corresponds to his wishes, and adjusts the cylinder head if necessary. Repeat this method of working, it can save you a lot of misery later on.
AMC
The cylinder heads of the CU and CV type 4 engines, which are only used in the Vanagon Bus, are equipped as standard with 39.3 mm intake valves. The 2-litre engines of the Bay Window Bus never exceeded 37.5 mm, while the 1700 and 1800 models were equipped with 39.3 valves. For all those working on type 4 engines, it makes sense to use these cylinder heads instead of the original with the smaller 2 mm intake valves. Also recommended for the original revision, this is an improvement over the original.
AMC cylinder heads are produced in Spain and are of very high quality. AMC with EMPI is the only manufacturer where you can mount the cylinder head directly. Nevertheless, a professional will dismantle everything to check with his own eyes and measuring devices if the cylinder head meets his wishes. We advise you to use this method of working again, when you work on the engine, you are 100% sure and leave nothing to chance.
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