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An alternative to the replacement of camshafts is the modification of original shafts. In case the shafts for your engine are not listed in our catalogue, or your budget availability is limited, you can choose this economic and rapid solution.

The modification of original shaft is the process through which the original lobes of the cams are rectified with a new profile. As the profiles ofsportive shafts are generally more developed, it's necessary to reduce the base circle in order to insert the new one, practically by obtaining a sporting cam 'inside' the original one. As a consequence, at this point you'll have a shaft with profiles having more developed cam lifts and shape than the original one and with a base circle having a reduced diameter.

If your motor is equipped with hydraulic tappets, no control will be required; in case of mechanic tappets it will be necessary to adjust clearance registers or to insert calibrated pads having a greater thickness in order to cover the clearance increased by the processing. In all cases the modified shaft is to be reassembled on original connections, with no need of specific timing. In order to carry out this process, it's necessary to send us the shafts, after disassembling pulleys, converter and all other parts, therefore leaving the shafts 'bare'.

After receiving the shafts, we will carry out a first phase of straightening (after disassembling shafts often tend to bend of some tenths of millimeter); afterwards, the original profile is read and the new profile is chosen by considering the quantity of material that is possible to remove and the amount of clearing that is possible to recover on the tappets. After choosing the profile, the rectification process and the thermal treatment, if required, with relation to the material the original shaft, are carried out . In about four or five working days from the reception we are therefore able to return the modified shaft, which will guarantee better performances and same toughness of the original shaft.