I Need help how do you retard the timing on a s2000 trying to run a 75 shot of nitrous on my s2000 need people that have nitrous on the S to help me i have been running a 55 shot for about 9 months now i know i have to retard the timing 4 degrease for a 75 shot but how do you retard the timing on the S

 

you need a ECU that can control ignition (greddy/aem/...)

 

And maybe a few punctuation marks and capital letters... ;-)