You have got my radar attention. Which Nissan car does he get the spring tensioner from, please?There is a man in OZ name Kelly Cork near Brisbane. He makes a tensioner from a Nissan cam chain tensioner. Many have been made and used. They press the tension from the inside out not the outside in. No modifications to case at all. They any change the chain tension in .030 increments so they never over do the tension. They are much more thought out and somewhat better priced than the other one as well. I have posted about this before. No one cares.