Running full 75 shot on a j30 motor, has 105k's & perfect fuel pressure. Nos is alot safer than it used to be. The Zex kit I run is a dry system and when initially set up we took the increases in 3 phases.
1) installed 55hp shot, advanced timing 2 deg. ran perfect over a 2 week period, stock plugs work fine.
2) installed 65hp shot, ran fuel pressure test & ran as above worked fine on stock plugs.
3) installed 75hp shot again checked fuel pressure & went to ngk 6's to help reduce plug temp, this helps to avoid detonation. Must run 92 or higher octane.
Good experience with the Zex dry set up, really works well and is perfectly safe but make sure you have a solid base b4 you go and add 75hp take the time to step thru the hp ranges and ensure your engine is burning the mixture right.
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