Cool head spark plugs loosening

[davidonmars]

Can anyone tell me why my

Spark plugs are

Coming loose? It's a cool head with 20cc 4 mill domes running 94 octane

[rubberneck]

detonation.  im not sure of your elevation but at sea level with 20cc domes on a 4mil i run 110 octane

[Finch]

put them in tighter.   Or fix your problem and run either bigger domes, or better fuel.

[shanYE west]

Trinity plug lock

[davidonmars]

At 155 psi I didn't think I'd need higher octane. I'm about 1000 above sea level

[davidonmars]

They were 23 mm I believe but then cut for 4mm dome has some engraving 20 13 115

[davidonmars]

Stock timing

[rubberneck]

hmmm 150 psi? you sure your gauge is accurate.  mine kicks 180 on a snap on guage

[sheerider1026]

Im running 160 on 93 pump. No issues. Dome design can make or break ya

[davidonmars]

I'm not sure who cut them I bought them off a member o the board. As far

As I can tell reading the numbers done

Volume is 20cc squish angle is 13 and 115 for long rod. Stock timing stock carbs 330 mains. I'll have to use another gauge tonight

[davidonmars]

Was using klotz super techniplate mixed 40:1 using 94 octane.

[lms1977]

How wide is the squish band what is the clearance etc??

[davidonmars]

Well race fuel is not readily available where I am not would I even know where to get it. I'd hate to spend even more

Money buying another set of domes and have them cut. Can someone help me

Out? Anyone want these domes

For a different set

More pump fuel friendly?

[davidonmars]

Who's the best place

To get them and can I get a number

[shanYE west]