OK, sorry to necropost here, but if the info in this thread is run against the hall site's specs for a 1" Orbit, the QEV simulates at 75% the fps the 1" does.

I thought 3/4 QEVs were supposed to outperform 1" modded sprinkler valves??

There's nothing wrong with reducing couplings other than most of them not being pressure rated, correct? I have the good ones available locally and like the look.

http://borgcollective.org/Images/air1.jpg
http://borgcollective.org/Images/air2.jpg
http://borgcollective.org/Images/air3.jpg ...

I would think that cutting these down to an inch or so and boring a big hole in the back end would work alright?...

CS and Tech;

This may clear up the dimensional differences and terminology used.

SDR-21 has 200 psi rating, hene the name "class 200".
SDR-26 has 160 psi rating. May be considered a class 160?

Note 1.680 is minimum golfball diameter.
If any one would like the spreadsheet let me know.

This is ...

ex3.jpg and ex2.jpg will probably have similar performance depending on chamber size and barrel length.

Download GGDT and play around with chamber size, amount of valves, barrel length etc to see which configuration is best for you. Any questions you have about GGDT can be answered by looking ...

I did look and search - I promise!

OK, I think dual QEV's is a fairly accepted model, and most designs I see have included some way of equalizing the pressure across two pressure chambers.

My question is this: Is there any advantage to two chambers with a small connection for equalization? In ...