Post Number: 15
|Posted on Monday, February 08, 2010 - 09:57 pm: ||
Folks, please forgive my ignorance but I am interested in whether using spark plugs with straight threads (such as the Motorcraft F11) in motors which have plugs with tapered (gas) threads recommended (such as Champion 25s)would create any problems. This is for my 10/12 Simplex but I understasnd bth are recommended for a T Model Ford.
Post Number: 245
|Posted on Tuesday, February 09, 2010 - 06:01 am: ||
I would think that would be a good way to strip about half of the threads out of the head.
Post Number: 82
|Posted on Tuesday, February 09, 2010 - 12:43 pm: ||
Someone tried that on my 4.5 "R" Gray. All that was left was a thread and a half. I had to drill the hole out to accomodate a 3/4 x 1/2 taper pipe bushing. I tapped the hole, screwed the bushing in using lock-tite on the threads. I then had to measure the clearance from the piston at TDC and find a spark plug with an extended reach that wouldn't be hit by the piston when running. The origonal plug was to short. A dead space was produced and sometimes when running the fuel and air mixture didn't fill that space which caused the engine to miss.