The D15Z1 is a pathetic engine, it's not truely even VTEC; it's VTEC-E. It mosty deactives one intake valve per cylinder at lower RPM's to run like a 12v, and locks them in to act like a standard 16v up in the higher RPM's. It comes from the Civic VX (92hp.) The only cam you can get for this engine would be a regrind, as well as a waste of time and money.

The standard VTEC system in the Sol runs a normal cam profile at low RPM, and a more aggressive profile at high RPM. Your Sol's engine (D16Z6, used in the del Sol Si, Civic EX and Si) is MUCH more powerful then your Civic's Z1 at 125hp.

If your friend is loosing control of a 92 horspower car... I feel sorry for him.