Sport runners that run 20% W/ 67 size motors

[m brater]

Hey sport runners that like to run on 20% nitro. Whats a good plug to run a 67 size motor? I was using mc59 but they seem to be delicate and blow easy. Thanks Mike.

 

[FloridaScaleBoater]

Hey sport runners that like to run on 20% nitro. Whats a good plug to run a 67 size motor? I was using mc59 but they seem to be delicate and blow easy. Thanks Mike.

Odonnell OD blues.

Last I purchased from Phils Hobbies

 

[m brater]

Rick thanks for the reply. I read on tower hobbies the blue was for 30-65%. I'm running 20%,have you tried them on 20%?

 

[FloridaScaleBoater]

Rick thanks for the reply. I read on tower hobbies the blue was for 30-65%. I'm running 20%,have you tried them on 20%?

The 30-65% is just a rule of thumb,, If you don't think they will be hot enough,, there's always the OD-Reds and purples

But no,, I haven't used them with 20%

If your going through MC59's, your next step up would be MC9's which is what I ran before trying the OD-blues.

 

[Rigged]

I ran OD Blue's in my K&B 67 and OPS 65's on 20% no problem.

 

[John Knight]

MC-59's are not the right plug for a 67 engine. Too hot of a heat range. The MC-9, the OD blues, OD 9 or OD 99's are better choices.

 

[jeff baham]

if you are running .012 to .014 head clearance k&b hp's, mcCoy 9 is what i used, 20 to 40% fuel will still give good top end speed, anything higher will give more exceleration out the corners.