190 kit

Apologies in advance for asking no doubt previously asked questions but I am trying to understand the Lotus 190 kit and the changes made to increase from 177bhp.

Specifically I’m interested to learn more about the cam timing that I understand was also adjusted as part of the VHPD upgrade.

Am I correct in thinking a different cam pulley was fitted with an additional machined slot to alter the timing?

If that is the case what was the principle behind this as the cams themselves I understand remained unchanged so surely the timing was already optimal for the standard cams?

Thanks in advance for any input folks.

Cheers

I’ve found the answer so posting here for reference should anyone else be curious

http://www.340r.net/upgrade.htm