Just got a new Zex nitrous kit. Part number 82015 on comp cams website. Its just a dry kit and im wondering what i will need to change to run a 75 shot. Should i change the spark plug gap? or do i have to get new plugs? ALso should i get a fuel pressure regulator? What do i need to make this kit more reliable and safe. Also 91 octane fuel is a must correct?
you need at least a 1 step colder plug. and a tune is a must IMO,but people have run them without tunes...and i would run 93 to avoid detonation.
I would suggest 93, a SCT XCAL 2 or similar, a wideband and a tune by a professional on a dyno if you want to run the shot safely. - Julia
i do believe that the 103 is one step colder...and IMO, i would run at least a 100 shot and two step colder plugs. a ZEX 75 shot is really a 65ish shot compared to other nitrous kits..
just confirmed it. Autolite 103 is one step colder. I would run the maximum shot that your dyno operator can keep in the safe A/F range.
do you have the window switch with the kit? If not i would highly reccomend one. I would gap em at .035" also.
I'd spray 100 instead of 75, but here's what you do... 1. Retard timing two degrees per 100 shot. 2. Install a WOT switch and a button, don't spray until 3000 rpm. (window switch is easier though) 3. Colder plugs gapped a .035 is fine, never use platinum. Only copper. 4. 91 Octane. 5. Make sure your jetting is correct. I've sprayed 175 on 5.0 motors with no fancy dyno tune or computer modifications. They were wet kits though. I'm not a fan of dry kits. Most kits have their jetting spec'd out pretty rich from the manufacturer to keep kids from blowing their shit up. I confirmed this suspicion when I sprayed a 250 shot plate kit on one of my motors (wet kit) and the A/F ratio was <10:1 with the factory jetting. Paul.
alright thanks for the help everyone. I have a pretty good idea of what im going to do. Now i just need to find out where the last vaccum line gets hooked up and ill be ready to go. O yeah...can i run these autolite 103's all the time, and it shouldnt hurt performance or anything right?
off the spray, you may notice a little hesitation with the one step colder plugs, then again you may not, it varies car to car. you won't hurt anything though.
u should run ngk tr6s, i do and love them gap them at .035. and a nitrous pressure gauge is a must if u dont got one (u should have though) make sure u are spraying between 3000-6000 rpms, and 91 octane will be fine im sure for ur location(from my understanding the octane varies from place to place due to altitude so not everywhere has the 93 at the pump allowing 91 to be efficient) but anyways, have fun with it and run a 100 shot. 75 is to small