ok i live in an area where we have plenty of 93 octane and was curious if it is safe to go with 75 shot after intake catback and midpipe or should i just stick with a 50 shot also has anyone dyno'd a 50 shot if so does it give you 50 hp or does it only give you like 20 you know just some normal inf would be good btw i did search to no avail. also is there any reson to go with zex if not im goin with NX i've always heard good things about them. also if the ecu doesn't pull enuff timing for 75 could you just use a larger fuel jet?

 

Lucky bastard. All we have is crappy oxygenated 91 over here. There was a poster here that has done a 75 shot, but the car was bone stock. From a few of the dynos on the air intake, it seemed to lean out the car a bit, so that you may get a bit of detonation with the 75 shot. We have a few posters here with a few mods, that are doing the Zex 55 shot. I have seen a 50 shot (not on the RX8 though) dyno & it gave a 38 whp increase (On an RSX Type S). We had a resident guru on the subject (although he had to go away for a while) who tried to run a 65 & 75 shot but got some detonation (with mods). Don't know about the larger jet question.

 

i can answer part of this as i nitrous guy, although i have NO experience with rotory motors. If the detonation is coming from an overly rich motor (which i'll bet you money it is since the kits are designed for piston motors and rotorys from my understanding like to run pig rich) then yes upping the fuel jet size will solve the proble.

On a piston motor these kits are generally jetted rich. What we used to due was jet the car for the shot we wanted or a little lower, then dyno. If the car was rich we would pull the nitrous jet and drill it out a hair and redyno untill we got a air fuel mixture we liked. this saved money from buying new jets. This could be done in a lean situation too by drilling the fuel jet. If it was me I would start with a smaller nitrous jet than i really wanted and drill it instead of a fuel jet thats too small and drilling it. Its a lot safer to be a little rich than lean.