Ok I'm new to the hole nitro motor thing. I've got this Dynamite .26 and I think I did a piss poor break in. I've got over a gallon and a half in it now of Dynamite blue thunder 30% nitro. I keep distroying glow plugs like not even getting through one tank. Ihave taken the motor apart sleeve and all and cleaned it and it ran fine for 4 tanks or so then bang the glow plus are going out again. now running it it does get to around 260 265 temp wise with good smoke trail.Im in north bay of california temps are in the 70 low 80's out side. Im getting really frustrated with this whole thing.. My .25 ran good but Ive got it apart to try and port it out so Im motor less in a way cuz of my situation. Please does anyone have a clue as to what I did wrong. Besides the piss poor break in?

It could be a bit too lean...and you could try a cooler plug...(or a little less nitro...or a shim under the head if you want to continue running 30%)
Mine will eat plugs (I run Monster Horsepower 25% ) if I don't let it gurgle just a bit (rich ) through transition and on the top end.

I agree with proptop....lower the compression with another head shim.

FBD.

Ok will try the shim do you think a shim from my .25 will work? if not I guess I can get them from MLHS hey thanks.

The shim has to be as close to a perfect fit as possable...so if the bore of the 2 different engines is the same, then it will work...but I kinda have my doubts?
You'd be best off to get new ones...say a .003" and .010" if you can get different thicknesses. (sometimes they come in a package of assorted thicknesses )