All you need to know about "Reboring an engine"
Reboring an engine Guide
To increase the power of an engine you can increase the cylinder capacity. The best way to increase the cylinder capacity of an engine is by physically making each cylinder a larger diameter.
Firstly sit down and do your research. You need to check that you can get a gasket, piston with rings and other components to match your chosen bore capacity. You cannot undo the reborn and certainly do not want to have to redo it again.
There are two main types of engine firstly the cast iron block and secondly the aluminium block. The cast iron blocks are good candidates for RE boring. It is recommended that you get the block stress tested before proceeding especially if you are making substantial changes to the diameter. Aluminium blocks may not be RE bored easily, but you may be able to get different size steel cylinder liners to achieve a similar effect.
We boring and engine is a specialist job and not something that can be performed at home unless you have a very accurate drilling machine. You cannot afford to drill off centre or you risk a piston going awol during some enthusiastic driving.
You'll also need to check that the head will fit on to your new cylinder capacity. You need to check that the gasket still provides an airtight seal. It is also a good idea that you get the head re machined to match the capacity you have selected, and this will help air flow into the engine.
Another option to increase the cylinder capacity of an engine is by using a stroker kit. This changes the length of the crank and when combined with a lower profile piston you are able to increase the amount of capacity within the cylinder.
Running in the engine after a rebore involves lots of low speed but high load driving. By this we mean plenty of hill work, towing and stop start driving. You must keep the revs of the engine and down during this time. It is also vital that you avoid oil additives which prevents the bedding in process from taking place effectively. If you have scored a crosshatch pattern into the cylinder wall this will help the piston and ring to bed in properly whilst the engine is under load.
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