Thoughts on spark plug gaps.....

[4sfed4]

I did a quick experiment today with the R/T. Instead of the usual 0.030" or so for the plug gap (Champion RN9YC plugs), I bumped them up to 0.040" to see if Id get any misfires under boost. I also made the car run very rich (EGTs in the low 1300's) to make the mixture even harder to ignite. Upon driving the car, I found that no abnormal effects were found.

Any of you guys have any ideas on how plug gap effects power output? Im thinking that theoretically power should improve with larger gaps. So, maybe it might be best to run the absolute biggest gap possible without misfiring.

Anyone messed with this?

I have a dyno appointment on Monday and I just might try a few different gaps and see if power output varies by anything significant.

[DakotaKid]

I have been told that the bigger the gap the better.

I have never tried a different gap on my car personally.

Let us know what you find.

-Bryan

[flybyuin2.2]

with DIS ignition they can get away with larger gap, the distributor type seem to have weaker spark or less direct spark and not as accurate causing missfire, let us know how it goes Larry, sounds interesting.

[1mean88z]

i am currently running .045 with my tona i do have msd 6al however i haven't dynoed to prove it but the car does seem to respond better.

[4sfed4]

Quote:

Originally posted by 1mean88z i am currently running .045 with my tona i do have msd 6al however i haven't dynoed to prove it but the car does seem to respond better.

Ill be dynoing tomorrow and hopefully will be able to test from 0.028 all the way up to whatever starts misfiring

[macncheese]

i think gap vs boost pressure would be interesting as well
tony

[4sfed4]

Quote:

Originally posted by macncheese i think gap vs boost pressure would be interesting as well tony

Holy mackerel........you sure do know how to spend dyno $$$!

LOL.

In seriousness, to keep the number of runs reasonable, I think I am going to test at the normal 0.032" gap Ive been using while increasing the boost pressure. Then, when I get to a certain power (i.e. boost) level, Ill stop adding boost and then just start increasing gap and see what happens.

[4sfed4]

Sorry guys....didnt have time on the dyno to do the spark plug gap tests....too many things going on.

But, you might find this interesting! I sure did!

http://td.rcwebdev.com/showthread.php?s=&threadid=40279