MonsterBilly

I am runing trick flow aluminum heads and i am also using a 200 shot of nitrous in my 66.

What spark plugs should i be using. I need to order them but im not sure which way to go?

nitrous_bob

1 step colder...2 if your scared

MonsterBilly

Please explain what you mean by colder. I bought a set if autolite platinum.
Can the temp. As you state be controlled by the gap?

nitrous_bob

NOOOOO !!!!

take those plugs back right now.

your car will better with NO plugs in it

take for instance autolite 24's a "hotter" plug would be a 25 and a colder plug would be a 23

gap has nothing to do with heat range.....but it has EVERYTHING to with boost and trying to stay away from detonation, and read your plugs OFTEN when you first start spraying....do it often anywyas...even after spraying a lot, its the best indicator of whats going on

you want to close the gaps up. honestly i wouldnt hit your car with 200 right out of the box...start at 100. gap stock coppers at about .042" , time it about 10* to be super safe and use about 91 octane

then you need to powertune it

make runs at the track, note the ambient conditions...temp, humidity

you can advance your timing in 2 degree increments with the SAME conditions...if it gets hotter...note that, if the airs gets thinner....note that as well

if you make the runs while bumping timing your MPH will slow down before you get too lean and hurt anything. dont mind ET...MPH is the indicator of power

if you blow a run...disregard it. if you smoke the tires....disregard it

anyways...... after you dial the car in...you can adjust any of the folloing but not necessarily all of them. but you may NEED to based on conditions that day

if its hotter than before....drop timing OR add octane

if its cooler or better air....add timing or drop octane

you have to know your car...and how it reacts to the smack

then increasing nitrous...do it all over again

25 hp bumps are no biggie...but going from 100 jets to 150 jets will require some modification

by the time you bump from 100 to 200 your timing will probably be retarded 4-6* over the 100 jets and plug gap will closed from .042" to about .036" or so

but a lot of that has to do with you...the gas you use...the conditions of that day...etc

alwyas err on safe....worst case scenario is you slow down a tenth or 2

go lean ? hopefully you just melt a plug...and not a piston

fyi..on a cool day like 70-ish on 80 jets, i can run 12* timing on 89 octane

but dont start there....work your way to "ragged" edge or you'll break something and then blame it all on the nitrous boogie man