First off...I'm running a 35 shot of nitrous, may eventually go to a 50 but the highest octane gas I can find close to my house it 91. I have to drive like 20 min. to the closest place with 100 octane. So is 91 too low of an octane to use with nitrous?? Should I just use an octane booster?

Second, my Denso Iridum plugs turned an orange/brown color after running nitrous. I heard this could be because of the octane booster. I may have had low bottle pressure and running a little rich also. Either way, I took out the Denso IK20s and put in some regular Champion, stock heat range copper plugs as I heard copper is the way to go. I was going to use a colder plug but I figured I'd see how they do. Should I be okay with these copper plugs??

I wanna run the Densos only when i'm running N/A. Should they still be okay even though they're brownish/orange. I didn't use them very long on the nitrous and only with a 35 shot.....

I'd post pics of the plugs, but my cam sucks at close ups....it's a cheapo

 

91 is ok to use. I use 91 since that is all I have around here as well for my turbo and it runs fine.

The plugs are orange/brown because you are running really rich. What sort of fuel management do you have to fuel the extra air flow that nitrous provides? I wouldn't go any hotter than one heat range colder than stock. Get one range colder or you risk melting the electrodes/detonation.

 

I just found some info online that said that the orange color was probably caused by the octane booster i put in yesterday....if I am running rich it's probably because my bottle pressure was low, I didn't have a guage on until today and then i found out it's only been at about 600psi because it's been kinda chlly out. I'm using an Apex VAFC II which until today I was adding a 1% correction from 4400 RPM and above, so that's another reason I was probably running rich....

So I should definately get 1 step colder plugs huh? I just put these cooper champions today, I'll check 'em in a week or so....they were only 6 bux so no big loss....I just didn't wanna mess up those Denso IK20s that ran about $56 for four of em....but Denso's website said to run the stock heat range up to an additonal 75-100 HP......

 

I got my Denso Iridiums one heat range colder brand new off ebay for $25 shipped.

 

I read on sparkplugs.com and densoiridium.com that you only need to go 1 step colder if you're adding 75-100 additional HP? Does that sound right? So if I'm running a 35 or 50 shot of nitrous I should be okay with the stock heat range right???

 

running a 35 shot shud be ok on a 91 octane fuel, though i've found the best plugs to use r the ngk iridiums...get em u wont b sry!

 

Oh wait, my bad. I had densos in there before and got a buttload of misfire engine codes, so I swapped out to NGK iridium and the misfires went away. I got the NGKs for $25 on ebay. The densos were bought at autozone for $30 and were complete garbage.

 

NGK iridium is the way to go?