• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

TR4/4A Spark plugs

bammons

Jedi Trainee
Country flag
Offline
If I have the 87mm piston/liner set and the BP270 Newman cam does this change my spark plug requirement? Bruce
 
Someone may have your same combination and have the perfect answer. In the mean time, I would recommend starting with the OEM plug and see how it runs. If it tends to foul or carbon up prematurely, move to a higher number for a “hotter” plug to keep the plug clean. If the plugs run for a while and come out chalk white, or you get detonation at normal timing settings, then move to a lower number plug, so it runs cooler.
 
Back
Top