Which One Is Colder? 103 or 104

i cant seem to find a straight answer. its just that i can get the autolites locally where the tr6's that im using right now i always have to order. kinda a PITA. Thanks

103s are colder

Autolites get colder as the number gets smaller.

Unless you are running A LOT of nitrous, the 104's
should be fine.

Emil Dusek:93Z,IRS383,Vortech,NX

now does heads and cam and having milled heads which ='s higher compression have a role to play in having colder plugs also. im running mid 11's here at 4800 ft above sea level and im going to vegas for the slp customer appreciation day in vegas and i want my **** running up to full par so i can bring back my 10 sec time slip ;)

I did same day tests at the track and with my 11.2 compression. I actually run 2 mph faster with the 103's. I made about 4 runs with the 104's, did a swap, then ran about 3 runs with the 103's. I was not spraying on any of the runs. But if you have stock compression, I am not sure you will see these same results. But it might be worth a try.

i am going to try the 104'S. you can get them at walmart, so they are cheaper and easier to find!