26-07-2021, 10:48 PM
Curiously, whilst a burned valve severely reduces Sevens, moderate ring gaps seem to have less effect. Older manuals allow quite large gaps for refitting, and ring manufacturers allow large tolerance even when new. Pre gapped rings often result in generous clearance, esp after run in.
For 40 years I ran my 1964 minx with poor comp on the handle and genrous blowby. The cars were fitted with large top gaps originally and the 2nd rings were externally stepped, provideing a large flow path. When eventually fixed idle was much improved but little other difference.
For 40 years I ran my 1964 minx with poor comp on the handle and genrous blowby. The cars were fitted with large top gaps originally and the 2nd rings were externally stepped, provideing a large flow path. When eventually fixed idle was much improved but little other difference.