The guys have covered most things but I have a few more details to add, although I could save myself (and YOU) the trouble if you'd just accept the BEST advice that has already been given and that is to DUMP those GARBAGE solenoids, as they are barely reliable when NOT pulsed.
The President of HolleyNOS told me in person, that they'd decided against replacing their solenoids with our Pulsoids, JUST BECAUSE THEY'D LOSE SO MUCH REVENUE FROM RECON KITS and that should be all I need to say to stop anyone using them.
Before I go in to all the other reasons why you should dump those solenoids, I have to point out a couple of points about your testing;
1) Testing the nitrous solenoid without FULL pressure applied is pointless.
2) If it had worked it wouldn't have been ANY indication of whether or not it would work under pressure.
3) If it doesn't pulse without pressure it is unlikely to pulse with pressure, unless it is actually opening and you haven't noticed it and if that was the case the pressure MAY result in it working
4) It is more likely that when pressure is applied it will be less likely to pulse
Even if you managed to get them working, besides the fact that they are barely reliable when NOT pulsed, there are other problems with not only the solenoids but also the other parts you'll be using in conjunction with them, that makes them TOTALLY UNSUITABLE for pulsing.
1) They are electrically INCOMPATIBLE so they will NOT pulse in sync with each other
2) They are mechanically INCOMPATIBLE so they will NOT pulse in sync with each other
3) Even if they pulsed in sync with each other the flow is INCOMPATIBLE and as a consequence the amount they flow is UNEVEN
4) Even if the solenoids pulsed in sync and the flows were even, the pipe work and jet locations will screw it all up, as metering MUST be carried out AT THE SOLENOID OUTLET and the bore and lengths of the pipe need to be minimal, to avoid that problem.
In a nutshell there is NOTHING about generic solenoids & US outlets from the solenoids that ISN'T TOTALLY WRONG.
If you still wish to use such JUNK, I suggest you repeat the test with the nitrous pressure applied and then report the results and you might also like to give me the flow capability of the solenoids and what power level you intend to use them for?
Before you waste your time doing that, might I suggest your time would be better spent reading this thread in our advanced section on the full story of why ONLY WON pulsed systems work correctly;
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