I'm using Henry Schmidt's Supertec Performance Cylinder Head Stud Kit,
SPTC-HSK-1, in my 87 3.2L to 3.4L twin plug build.
From
twin plug ignition: 12mm or 14mm spark plugs
Quote:
Originally Posted by Henry Schmidt
14mm work fine. I have never seen a failure based on this modification.
The compression loss is minimal but accurately dimensioning your engine will allow you to order your pistons to compensate for the chamber volume change.
One cure for head stud nut clearance is Supertec head studs. They offer improved head to cylinder stability,greatly improve engine assembly and the nuts offer clearance for lower spark plugs.
https://www.pelicanparts.com/More_Info/SPTCHSK1.htm?pn=SPTC-HSK-1&bt=Y&fs=0&SVSVSI=911M |
Edit
Scott and I are refencing the same thread.