TechT QEPH - By venting the gas quickly, the loader responds instantly. This equates to faster loading with lower pressure. The standard A5 piston housing has no venting ports (very bad). X7 Piston housing has forward exhaust ports only (better). Meaning that it only exhausts the air that is in front of the piston....not behind it. Its the air behind the piston that is doing all the work and really needs to be vented in order for faster loading.
The TechT QEPH is newer, so it should be commonly available, both new and used.
Tippmann A-5 primary::
PPS Brass barrel w/ Apex tip
Palmer's Male Stabilizer
Armson Prodot sight w/ Lapco offset rail
OPSGEAR G36 folding stock
CMI micro-coil remote
Does what it advertises
Needs occasional oiling
Possible over-rotation issue (see review)
I picked up one of these from my local shop because I had some money to burn and I wanted to see if it worked better than a QEV. It turns out that it does.
First, lets deal with the mechanics of it:
A QEV has a spring that air has to initially overcome, which pushes a valve open, allowing the air to pass through as long as the pressure is maintained. Pressure drops off, the valve closes again. When pressure tries to travel back the way it came, since the valve has closed off the path it came through, air is then diverted out of the fitting through a port on the opposite side of the valve, exhausting it.
The QEPH works by allowing air into the piston freely. The piston then gathers speed, and when the piston has enough momentum to complete it's travel without pneumatic assistance, the gas is exhausted out the side of the piston. As the piston travels back, any air that would provide resistance to the piston's return is vented through the same slots.
Because air traveling through the QEPH does not have to initially overcome the pressure of a QEV spring, it is quicker to reach the piston and the cyclone reacts faster. Also, because the QEPH exhausts air on both the piston's intake and exhaust stroke rather than just the exhaust stroke like a QEV, it provides less air resistance on the piston, resulting in a smoother acting cyclone.
I've seen that some folks have some concerns with getting dirt and debris in those giant ports and messing things up. I'd like to put those concerns to rest now. Sure, it's possible to get stuff in there, but as soon as you take a shot, it's all forced back out again. The relatively small amount of material that can get through the holes is no match for the relatively high pressure pneumatic system at work here. I've been shot directly on the housing, with paint visibly coating the inside of the thing. After one shot, 95% of what was in there was forced out (somewhat messily), and a second shot cleaned it the rest of the way. Unless you physically pack the inside of the housing with dirt, I don't think you're going to be able to get it to stop operating.
Now on to the potential problems. First, it does need an oiling once in a while. Not an insane amount, just a drop or two every couple of gun cleanings. The internal surface is incredibly smooth, so if it's dry, the o-ring that pushes the piston gets great traction. Think drag racing slicks on a smooth track. And just like the slicks, when you introduce a lubricant, it slides all over the place.
There is one thing that could pose a problem severe enough to make you hate it. The problem arises from also having either a Vortex or Jet click. We'll stick with discussing the Vortex, because that's where I know the issue is. When you install the Vortex, they tell you to clip the internal spring so that it will reduce pressure on the axle and allow the cyclone to rotate easier. I don't think they took into account back then that they would be making several other pieces that would also improve the rotation ease of the cyclone.
Since both the QEPH and the Vortex were designed to make the cyclone rotate easily, putting them together should make the cyclone almost rotate on it's own. Which it does. And though you might think that's good, it could cause problems. If the cyclone spins so easily that the piston return spring spins the paddles with enough force to create momentum, the cyclone could over rotate, spinning two or three times with each shot. This would cause extra loading and ball breakage. I only ever saw this problem when the hopper was almost empty, but it was there.
There is, however, an easy fix. Remember that spring inside the Vortex that you clipped shorter? Now we need it to be stronger to provide more resistance on the axle. All you've got to do is replace the spring you clipped when installing the Vortex with your stock trigger spring (the red one). That spring is identical to the one you originally clipped, and will take care of your over-rotation problem.
If you really want to get the most out of your cyclone, pick one up. Just be prepared for a little troubleshooting. It's definitely not necessary to have one, but it will absolutely make your cyclone faster.
I'm giving it a 10 because as long as you set it up right, it does exactly what you bought it for with no drawbacks.
10 out of 10
Last edited on Thursday, November 15th, 2007 at 8:49 am PST
ops gear g36c foregrip/sight rail
opsgear g36c mag
opsgear g36c folding stock
ops gear operator m4 barrel (16 inch)
bt bipod, bt bipod barrel adapter
tiberius laser site
tiberius tactical flashlight
techt vortex mod
techt cyclone feed lightning rod
jt tactical sling
tiberius vertical fore grip
oranged howitzer bolt
rap4 hopper offset
pen spring mod
Increased air effiecency, increased bps, looks cool
This thing is great i have the vortex mod, lightning rod, and now the qeph and my cyclone just flies when im going full auto. it cycles smoother, it works until my tank farts out now which it great i dont have to manual reload any more when im low on air. its worth it if your trying to get your a5 to fire faster and save air
It does what it says. it saves air, works at lower psi, and feeds at higher bps its a good buy
Raises cyclone feed rate
Works as advertised
Have to clean after each day of playing
This definitely does what it advertises. it vents the air much more efficiently than a QEV does and it allows the cyclone to cycle much faster. my rate of fire went from 19-24bps with this. The only thing is that you have to make sure it's well lubed and cleaned after each day of play. This is because of the openings in housing being slits instead of holes. I have been talking with the manufacturer and they are looking into possibly making them holes but I haven't had anything other than dust and a little grit get into my QEPH. Definitely a great product!
Vents air well
Makes cyclone spin faster
Better design than X7 version
Have to lube ever so often
Keeping it clean due to the large ports
I've installed, tested and used my QEPH. I have had it for two weeks ( I was one of the fist to get one of these). it works great. It does it job of venting air and spinning the cyclone faster so well. My cyclone has never spun so freely. Shot 3000 rounds through it with the rampage board set at 25 BPS and not 1 break in barrel or 1 chop in cyclone. It helps the cyclone keep up easily at 25 BPS with the other mods listed above. It's a great product and has out performed the past QEV's I've used. It's designed to work with the other upgrades as a system and that's how it performs best. it's easy to install.. make sure you drop some oil inside of it to lube the o-ring when first installing it
need video proof of what it can do? I gotcha covered. Copy this link and watch as I show you a range test of the system.
I give this product an A+ Tech-T has once again made a nice product.
Easy to install
Vents Air great