I must say your definitely approaching this better now, but your initial post was quite inflammatory IMO......These guys work hard to provide a good solid product, and its not nice to make such comments in the open forums....At least not before you exhausted all other means privately...... Your initial post did not seem like you were looking for answers, it looked like you were bashing the EB JS..... I am not intending to get involved or take sides...just saying what I interpreted from your initial post is all......

I am not much of a fan of the 97T myself..I tend to run my engines with a little higher compression and those plugs don't like that at all..... The 97T is far too hot for any of my own modifieds and will cause all sorts of tuning issues....The other thing is that in a modified engine you will go thru 3 97T's in the time you will go thru one OSp4 or P5....so your really not saving money in the overall picture with a 97T

the right plug would help.

+1,000 times but apparently i cant say it enough
that would be the best thing.

which is worse paying $12 for a plug or having your engine not run, and possibly detonate?

for sure. i said i was sorry thats over with i moved on obviously joe has not.... since he likes to roll his eyes at me...

just trying to get my friends engine running good! tired of him having problems.... and since the nova challenge race is just around the corner i want this motor to do well for him... maybe take out some toro's at their own race!

so your saying an odonnell plug can kill his motor?



never herd a plug "detonate" a motor... tell me why that is joe.... never heard that

why are motors so sensitive to plug brands.... or p4 is close to a 99t right?

medium plug?

He's telling the truth ....

the glowplug is a means to tune your engines ignition timing..a 97T is a very hot running plug which advances your timing, this works great on lower compression stock engines, as the lower compression tends to retard your ignition timing, and the 97T compensates nicely for that...However in a modified engine that runs higher compression you do not want to run such a hot plug...as the higher compresion tends to advance ignition timing on its own, so when you add such a hot plug you run the risk of detonating the engine...basically your are firing the mixture too early in the compression stroke which leads to all sort of possible issues...such as pitting of the piston and button, dropping glowplug coils and in the worst cases shattering the piston and rod....Having proper ignition timing is critical to these engine... the higher the compression, the cooler the plug you want to run..... myself I found the 97T's to be unsuitable for my modified engines...

yes a plug that is MUCH too hot can absolutely kill an engine, especially ours, or Neals that are setup with HI compression.

thanks for the info fellas... i passed it along to single.


like i asked though, would a 99t be better? or just stick with p4 os plugs?

you beat me to it..
+1... to the tee.

The OD99 may work, as I have some guys who have used them...however in the higher compression modifieds they tend to wear our pretty quickly.. I think the filaments are maybe a little too thin for the applicationm, the OS plugs seem to be built a little beefier and seem to last a fair bit better....But the OD99 is definitely a step in the right direction and at least worth trying...However I may be speaking a little off base, as I have no experience with the JS engine...JPalesi is the guy to know for sure if the OD99 is compatible.....

odonnell 97t is a medium plug..

odonnell 99t is a cold plug.

os p3 is a "ultra hot"

os p4 is a "super hot"

i dont get it, the odonnell plugs must be labeled wrong or is it os wrong?

why would a super hot plug be better then a medium? when you say the medium plug from odonnell is hotter?

on a main the p4 is 7 bucks so its 2 bucks more... lol... anyways, on a side note..
i run od 97t in my alpha engines. one plug was used to break in one motor then went about a gallon after that.
and is now in my other alpha that is being broken in. but i am changing it out before i start race tuning it..

i have had GREAT luck with the odonnell plugs lasting a while..
it dose not mean that os plugs are any less though. i just have motors that run well on the cheaper plugs..

thanks for the assistance Neal you truly have more patience then I.. The OD 99 can work, but in my honest opinion its still too hot, and does not run or last nearly as long as a p4 or P5. I have buying and have great success with P5's and plan to keep it that way.

different companies rate things differently...since there are quite a few factors that determine a glowplugs timing its difficult to have a standardized rating system..... the things that affect a glowplugs heat range are..mass of glowplug body, the more mass it has, the more heat it stores, filament diameter, the thinner the filament the hotter, as well as filament exposure in the plug body...the more exposed the filament, the hotter the plug...and lastly filament composition and coating... The higher the amount of Titanium, the more reactive the the plug is.......... So unfortunately it basically leaves us to trial and error to find the right plug...from my experience all the OD plugs are very hot, with very large bodies...... even tho the OS P4 is listed as hotter, it seem to function cooler......... I am not by any eans a glowplug expert, so this is the best I can offer on the subject...